Active-Active Failover on an ASA

When the ASAs are running multiple security contexts, the contexts can be organized into groups. Both ASAs are actively involved in providing security functions, but not in the same security context simultaneously. The active-active failover mode provides both device redundancy and load balancing across contexts.

Configuring active-active failover is similar to configuring active-standby mode. The two failover units need the same LAN failover and stateful failover link configurations, and the same active and standby addresses on each interface. However, each ASA must be assigned its primary and secondary role in each of the two failover groups. As well, each security context must be assigned to a failover group.

ASA1# show mode
Security context mode: multiple

ASA1# show context    // ALL CONTEXTS NEEDS TO BE DONE IN ASA1
Context Name      Class      Interfaces           URL
*admin            default    GigabitEthernet0     disk0:/admin.cfg
 CONTEXT-A        default    GigabitEthernet1,    disk0:/CONTEXT-A.cfg  
                             GigabitEthernet2
 CONTEXT-B        default    GigabitEthernet1,    disk0:/CONTEXT-B.cfg
                             GigabitEthernet2

Total active Security Contexts: 3

ASA1# configure terminal
ASA1(config)# failover ?

configure mode commands/options:
  group             Configure/Enable failover group
  interface         Configure the IP address to be used for failover and/or
                    stateful update information
  interface-policy  Set the policy for failover due to interface failures
  key               Configure the failover shared secret or key
  lan               Specify the unit as primary or secondary or configure the
                    interface and vlan to be used for failover communication
  link              Configure the interface and vlan to be used as a link for
                    stateful update information
  mac               Specify the virtual mac address for a physical interface
  polltime          Configure failover poll interval
  replication       Enable HTTP (port 80) connection replication
  timeout           Specify the failover reconnect timeout value for
                    asymmetrically routed sessions
  <cr>

exec mode commands/options:
  active          Make this system to be the active unit of the failover pair
  exec            Execute command on the designated unit
  reload-standby  Force standby unit to reboot
  reset           Force an unit or failover group to an unfailed state
ASA1(config)# failover group ?

configure mode commands/options:
  <1-2>  group number
ASA1(config)# failover group 1   // CONFIGURE FAILOVER GROUP UNDER SYSTEM CONTEXT
ASA1(config-fover-group)# ?

Failover User Group configuration mode:
  help              Help for user Failover Group configuration commands
  interface-policy  Set the policy for failover due to interface failures
  mac               Specify the virtual mac address for a physical interface
  no                Remove user failover group configuration
  polltime          Configure failover interface polling interval
  preempt           Allow preemption of lower priority active unit
  primary           Primary unit has higher priority
  replication       Configure the replication option
  secondary         Secondary unit has higher priority
  <cr>
ASA1(config-fover-group)# primary
ASA1(config-fover-group)# preempt ?

fover-group mode commands/options:
  <1-1200>  Preemption hold-down delay in seconds
  <cr>
ASA1(config-fover-group)# preempt 120
ASA1(config-fover-group)# exit
ASA1(config)# failover group 2
ASA1(config-fover-group)# secondary
ASA1(config-fover-group)# preempt 120
ASA1(config-fover-group)# exit
ASA1(config)# context ?

configure mode commands/options:
  WORD  Symbolic name of the context
ASA1(config)# context admin
ASA1(config-ctx)# ?

Context configuration commands:
  allocate-interface   Allocate interface to context
  allocate-ips         Allocate IPS virtual sensor to context
  config-url           Configure URL for a context configuration
  description          Provide a description of the context
  exit                 Exit from context configuration mode
  help                 Interactive help for context subcommands
  join-failover-group  Join a context to a failover group
  member               Configure class membership for a context
  no                   Negate a command
ASA1(config-ctx)# join-failover-group ?

context mode commands/options:
  <1-2>  Failover group number
ASA1(config-ctx)# join-failover-group 1   // ALL CONTEXTS ARE UNDER FAILOVER GROUP 1 BY DEFAULT
ASA1(config-ctx)# exit
ASA1(config)# context CONTEXT-A
ASA1(config-ctx)# join-failover-group 1
ASA1(config-ctx)# exit
ASA1(config)# context CONTEXT-B
ASA1(config-ctx)# join-failover-group 2
ASA1(config-ctx)# exit
ASA1(config)# failover lan unit primary
ASA1(config)# failover lan interface LAN-FAILOVER gigabitethernet4
INFO: Non-failover interface config is cleared on GigabitEthernet4 and its sub-interfaces
ASA1(config)# failover link STATEFUL-FAILOVER gigabitethernet5
INFO: Non-failover interface config is cleared on GigabitEthernet5 and its sub-interfaces
ASA1(config)# failover interface ip LAN-FAILOVER 1.1.1.1 255.255.255.252 standby 1.1.1.2
ASA1(config)# failover interface ip STATEFUL-FAILOVER 2.2.2.1 255.255.255.252 standby 2.2.2.2
ASA1(config)# prompt hostname context
ASA1(config)# changeto context admin
ASA1/admin(config)# interface ?

configure mode commands/options:
  GigabitEthernet  Prefix of interface GigabitEthernet0
ASA1/admin(config)# interface GigabitEthernet0
ASA1/admin(config-if)# ip address 192.168.1.1 255.255.255.0 standby 192.168.1.10
ASA1/admin(config-if)# nameif inside
INFO: Security level for "inside" set to 100 by default.
ASA1(config)# changeto context CONTEXT-A
ASA1/CONTEXT-A(config)# interface ?

configure mode commands/options:
  GigabitEthernet  Prefix of interface GigabitEthernet1, 2
ASA1/CONTEXT-A(config)# interface GigabitEthernet1
ASA1/CONTEXT-A(config-if)# ip address 10.1.1.1 255.255.255.0 standby 10.1.1.2
ASA1/CONTEXT-A(config-if)# nameif inside
INFO: Security level for "inside" set to 100 by default.
ASA1/CONTEXT-A(config-if)# interface GigabitEthernet2
ASA1/CONTEXT-A(config-if)# ip address 100.1.1.1 255.255.255.0 standby 100.1.1.10
ASA1/CONTEXT-A(config-if)# nameif outside
INFO: Security level for "outside" set to 0 by default.
ASA1/CONTEXT-A(config-if)# changeto context CONTEXT-B
ASA1/CONTEXT-B(config)# interface ?

configure mode commands/options:
  GigabitEthernet  Prefix of interface GigabitEthernet1, 2
ASA1/CONTEXT-B(config)# interface GigabitEthernet1
ASA1/CONTEXT-B(config-if)# ip address 10.2.2.1 255.255.255.0 standby 10.2.2.2
ASA1/CONTEXT-B(config-if)# nameif inside
INFO: Security level for "inside" set to 100 by default.
ASA1/CONTEXT-B(config-if)# interface GigabitEthernet2
ASA1/CONTEXT-B(config-if)# ip address 100.1.1.2 255.255.255.0 standby 100.1.1.20
ASA1/CONTEXT-B(config-if)# nameif outside
INFO: Security level for "outside" set to 0 by default.
ASA1/admin(config-if)# changeto system
ASA1(config)# failover   // TURN ON FAILOVER
ASA1(config)# write memory ?

exec mode commands/options:
  all  Save active configuration of all contexts
  <cr>
ASA1(config)# write memory all   // SAVES THE SYSTEM AND ALL CONTEXT CONFIG
Building configuration...
Saving context :           system : (000/003 Contexts saved)
Cryptochecksum: e2069dad 2bdfd7b9 72185fee ec97e572

1676 bytes copied in 2.900 secs (838 bytes/sec)
Saving context :            admin : (001/003 Contexts saved)
Cryptochecksum: 0c6c2cb2 f1e5ef63 2311e990 0e51dd35

1663 bytes copied in 6.60 secs (277 bytes/sec)
Saving context :        CONTEXT-A : (002/003 Contexts saved)
Cryptochecksum: 1f6496fd 95ddb896 1163aca7 84e63309

1716 bytes copied in 2.800 secs (858 bytes/sec)
Saving context :        CONTEXT-B : (003/003 Contexts saved)
Cryptochecksum: adbc43d2 a55eee49 870d28ba 6f058996

1716 bytes copied in 2.220 secs (858 bytes/sec)
[OK]
ASA1(config)# .

        No Response from Mate    // ASA2 ISN'T CONFIGURED YET

        Group 1 No Response from Mate, Switch to Active

        Group 2 No Response from Mate, Switch to Active


ASA1(config)# show failover
Failover On
Failover unit Primary
Failover LAN Interface: LAN-FAILOVER GigabitEthernet4 (up)
Unit Poll frequency 1 seconds, holdtime 15 seconds
Interface Poll frequency 5 seconds, holdtime 25 seconds
Interface Policy 1
Monitored Interfaces 5 of 60 maximum
Version: Ours 8.4(2), Mate Unknown
Group 1 last failover at: 10:11:48 UTC Nov 3 2013
Group 2 last failover at: 10:11:48 UTC Nov 3 2013

  This host:    Primary
  Group 1       State:          Active
                Active time:    106 (sec)
  Group 2       State:          Active
                Active time:    106 (sec)

                  admin Interface inside (192.168.1.1): Normal (Waiting)
                  CONTEXT-A Interface inside (10.1.1.1): Normal (Waiting)
                  CONTEXT-A Interface outside (100.1.1.1): Normal (Waiting)
                  CONTEXT-B Interface inside (10.2.2.1): Normal (Waiting)
                  CONTEXT-B Interface outside (100.1.1.2): Normal (Waiting)

  Other host:   Secondary
  Group 1       State:          Failed
                Active time:    0 (sec)
  Group 2       State:          Failed
                Active time:    0 (sec)

                  admin Interface inside (192.168.1.10): Unknown (Waiting)
                  CONTEXT-A Interface inside (10.1.1.2): Unknown (Waiting)
                  CONTEXT-A Interface outside (100.1.1.10): Unknown (Waiting)
                  CONTEXT-B Interface inside (10.2.2.2): Unknown (Waiting)
                  CONTEXT-B Interface outside (100.1.1.20): Unknown (Waiting)

Stateful Failover Logical Update Statistics
        Link : STATEFUL-FAILOVER GigabitEthernet5 (up)
        Stateful Obj    xmit       xerr       rcv        rerr
        General         0          0          0          0
        sys cmd         0          0          0          0
        up time         0          0          0          0
        RPC services    0          0          0          0
        TCP conn        0          0          0          0
        UDP conn        0          0          0          0
        ARP tbl         0          0          0          0
        Xlate_Timeout   0          0          0          0
        IPv6 ND tbl     0          0          0          0
        SIP Session     0          0          0          0
        Route Session   0          0          0          0
        User-Identity   0          0          0          0

        Logical Update Queue Information
                        Cur     Max     Total
        Recv Q:         0       0       0
        Xmit Q:         0       0       0
ASA1(config)# show failover state

               State          Last Failure Reason      Date/Time
This host  -   Primary
    Group 1    Active         None
    Group 2    Active         None
Other host -   Secondary
    Group 1    Failed         Comm Failure             10:12:05 UTC Nov 3 2013
    Group 2    Failed         Comm Failure             10:12:05 UTC Nov 3 2013

====Configuration State===
====Communication State===


----


ASA2# show mode
Security context mode: multiple
ASA2# dir *.cfg

Directory of disk0:/*.cfg

89     -rwx  2146         09:09:26 Nov 03 2013  old_running.cfg
90     -rwx  1417         09:09:28 Nov 03 2013  admin.cfg

268136448 bytes total (267481088 bytes free)
ASA2# delete *.cfg  // DELETE CONFIG FILES BEFORE FAILOVER/REPLICATION FROM ASA1

Delete filename [*.cfg]?

Delete disk0:/old_running.cfg? [confirm]

Delete disk0:/admin.cfg? [confirm]

ASA2(config)# interface gigabitethernet4
ASA2(config-if)# no shutdown
ASA2(config-if)# interface gigabitethernet5
ASA2(config-if)# no shutdown
ASA2(config-if)# exit
ASA2(config)# failover lan interface LAN-FAILOVER gigabitethernet4
INFO: Non-failover interface config is cleared on GigabitEthernet4 and its sub-interfaces
ASA2(config)# failover interface ip LAN-FAILOVER 1.1.1.1 255.255.255.252 standby 1.1.1.2
ASA2(config)# failover
ASA2(config)# .

        Detected an Active mate
Beginning configuration replication from mate.
ERROR: Password recovery was not changed, unable to access
the configuration register.
Removing context 'admin' (1)... Done
COREDUMP UPDATE: open message queue fail: No such file or directory/2
INFO: Admin context is required to get the interfaces
Creating context 'admin'... Done. (2)

WARNING: Skip fetching the URL disk0:/admin.cfg
INFO: Creating context with default config
INFO: Admin context will take some time to come up .... please wait.
Creating context 'CONTEXT-A'... Done. (3)

WARNING: Skip fetching the URL disk0:/CONTEXT-A.cfg
INFO: Creating context with default config
Creating context 'CONTEXT-B'... Done. (4)

WARNING: Skip fetching the URL disk0:/CONTEXT-B.cfg
INFO: Creating context with default config
Crashinfo is NOT enabled on Full Distribution Environment

        Group 1 Detected Active mate

        Group 2 Detected Active mate
End configuration replication from mate.

ASA1(config)# show context
Context Name      Class      Interfaces           URL
*admin            default    GigabitEthernet0     disk0:/admin.cfg
 CONTEXT-A        default    GigabitEthernet1,    disk0:/CONTEXT-A.cfg
                             GigabitEthernet2
 CONTEXT-B        default    GigabitEthernet1,    disk0:/CONTEXT-B.cfg
                             GigabitEthernet2

Total active Security Contexts: 3

ASA1(config)# show failover state

               State          Last Failure Reason      Date/Time
This host  -   Secondary
    Group 1    Standby Ready  None
    Group 2    Standby Ready  None
Other host -   Primary
    Group 1    Active         None
    Group 2    Active         None

====Configuration State===
        Sync Done - STANDBY
====Communication State===
        Mac set

ASA1(config)#
        Group 2 preempt mate   // AFTER 120 SECONDS


ASA1(config)# show failover state

               State          Last Failure Reason      Date/Time
This host  -   Secondary
    Group 1    Standby Ready  None
    Group 2    Active         None
Other host -   Primary
    Group 1    Active         None
    Group 2    Standby Ready  None

====Configuration State===
        Sync Done - STANDBY
====Communication State===
        Mac set



----


ASA1(config)# Beginning configuration replication: Sending to mate.

INFO: Issuing "tls-proxy maximum-sessions 10000" command due to license change

INFO: "tls-proxy maximum-sessions" config is changed, please save the running-config before system

reboot
End Configuration Replication to mate

ASA1(config)# prompt hostname priority context state   // TELL CLI PROMPT TO INDICATE
PRIMARY/SECONDARY, CONTEXT AND ACTIVE/STANDBY STATE
ASA1/pri/act(config)# changeto context admin
ASA1/pri/admin/act(config)# http server enable   // ENABLE ASDM/HTTPS ACCESS
ASA1/pri/admin/act(config)# http 0 0 inside 


----


ASA1/pri/act(config)# no failover active   // ASA2 WILL BE THE ACTIVE FIREWALL FOR BOTH GROUP 1 AND 2
ASA1/pri/stby(config)# show failover state

               State          Last Failure Reason      Date/Time
This host  -   Primary
    Group 1    Standby Ready  None
    Group 2    Standby Ready  None
Other host -   Secondary
    Group 1    Active         Comm Failure             10:12:05 UTC Nov 3 2013
    Group 2    Active         Comm Failure             10:12:05 UTC Nov 3 2013

====Configuration State===
        Sync Done
====Communication State===
        Mac set


As with active-standby failover, you can use the ASDM High Availability and Scalability Wizard to configure both the primary and secondary ASAs from the primary unit. To do that, double-click the System context in the device list. Then navigate to Configuration > Device Management > High Availability and select HA/Scalability Wizard.

Otherwise, you can configure active-active failover on the primary and secondary units manually. On the primary unit, double-click the System context in the device list, and then navigate to Configuration > Device Management > High Availability and select Failover.

Active-Standby Failover on an ASA

To coexist as a failover or redundant pair, two ASAs must be identical (in terms of hardware and IOS) and must coordinate their failover roles. In an active-standby failover, one ASA must function as the active unit, handling all traffic inspection at any given time. The other ASA must always sit idle, waiting to take over the active role.

The ASA pair must also share identical sets of interfaces. For example, each unit has an inside and an outside interface, and the similar interfaces must be connected together. This is for two reasons:

* The standby unit must be ready to take over handling traffic at any time, so its interfaces must be connected and ready to use.

* The two ASAs monitor each other's health by communicating over each of their interfaces.

If a failure is detected on the active unit, the two ASAs effectively swap roles. The ASA previously in the standby mode has now moved into the active role.

If an ASA moves into the standby role, it is not permitted to preempt its peer and take over the active role again - unless the active ASA has a failure of its own. This creates a stable mechanism where the ASAs toggle roles only when failures occur.

State Information Replicated

NAT table entries

ARP table entries

MAC address table entries

UDP connections

TCP connections

H.323 and SIP signaling sessions

MGCP connections

HTTP connections (if explicitly enabled)

Dynamic routing table entries (beginning software release 8.4)


State Information Not Replicated

User authentication Cut-through Proxy

DHCP server address leases

Phone proxy information

Security Services Module activity


We start by verifying the license support for the failover feature and performing a no shutdown command on the interfaces to be used.

Licensed features for this platform:
Maximum Physical Interfaces       : Unlimited      perpetual
Maximum VLANs                     : 100            perpetual
Inside Hosts                      : Unlimited      perpetual
Failover                          : Active/Active  perpetual  
VPN-DES                           : Enabled        perpetual
VPN-3DES-AES                      : Enabled        perpetual
Security Contexts                 : 2              perpetual
GTP/GPRS                          : Disabled       perpetual
AnyConnect Premium Peers          : 5000           perpetual
AnyConnect Essentials             : Disabled       perpetual
Other VPN Peers                   : 5000           perpetual
Total VPN Peers                   : 0              perpetual
Shared License                    : Disabled       perpetual
AnyConnect for Mobile             : Disabled       perpetual
AnyConnect for Cisco VPN Phone    : Disabled       perpetual
Advanced Endpoint Assessment      : Disabled       perpetual
UC Phone Proxy Sessions           : 2              perpetual
Total UC Proxy Sessions           : 2              perpetual
Botnet Traffic Filter             : Disabled       perpetual
Intercompany Media Engine         : Disabled       perpetual

This platform has an ASA 5520 VPN Plus license.

ASA1# show interface | include Interface
Interface GigabitEthernet0 "inside", is up, line protocol is up
Interface GigabitEthernet1 "outside", is up, line protocol is up
Interface GigabitEthernet2 "", is administratively down, line protocol is up
Interface GigabitEthernet3 "", is administratively down, line protocol is up
Interface GigabitEthernet4 "", is administratively down, line protocol is up
Interface GigabitEthernet5 "", is administratively down, line protocol is up
ASA1# configure terminal
ASA1(config)# interface gigabitethernet3    // LAN-BASED FAILVOER
ASA1(config-if)# no shutdown
ASA1(config-if)# interface gigabitethernet4    // STATEFUL FAILOVER
ASA1(config-if)# no shutdown
ASA1(config-if)# interface gigabitethernet0
ASA1(config-if)# ip address 192.168.1.1 255.255.255.0 standby 192.168.1.2
Waiting for the earlier webvpn instance to terminate...
Previous instance shut down. Starting a new one.
ASA1(config-if)# interface gigabitethernet1
ASA1(config-if)# ip address 100.1.1.1 255.255.255.0 standby 100.1.1.2
ASA1(config-if)# exit
ASA1(config)# failover ?

configure mode commands/options:
  interface         Configure the IP address to be used for failover and/or
                    stateful update information
  interface-policy  Set the policy for failover due to interface failures
  key               Configure the failover shared secret or key
  lan               Specify the unit as primary or secondary or configure the
                    interface and vlan to be used for failover communication
  link              Configure the interface and vlan to be used as a link for
                    stateful update information
  mac               Specify the virtual mac address for a physical interface
  polltime          Configure failover poll interval
  replication       Enable HTTP (port 80) connection replication
  timeout           Specify the failover reconnect timeout value for
                    asymmetrically routed sessions
  <cr>

exec mode commands/options:
  active          Make this system to be the active unit of the failover pair
  exec            Execute command on the designated unit
  reload-standby  Force standby unit to reboot
  reset           Force an unit or failover group to an unfailed state
ASA1(config)# failover lan ?

configure mode commands/options:
  interface  Configure the interface and vlan to be used for failover
             communication
  unit       Configure the unit as primary or secondary
ASA1(config)# failover lan interface ?

configure mode commands/options:
  WORD  Specify the interface name
ASA1(config)# failover lan interface LAN-FAILOVER ?

configure mode commands/options:
  WORD  Specify physical or sub interface
  <cr>
ASA1(config)# failover lan interface LAN-FAILOVER gigabitethernet4
INFO: Non-failover interface config is cleared on GigabitEthernet4 and its sub-interfaces
ASA1(config)# failover interface ?

configure mode commands/options:
  ip  Configure the IP address and mask after this keyword
ASA1(config)# failover interface ip ?

configure mode commands/options:
Current available interface(s):
  LAN-FAILOVER  Name of interface GigabitEthernet4
ASA1(config)# failover interface ip LAN-FAILOVER ?

configure mode commands/options:
  Hostname or A.B.C.D  Specify the IP address
  X:X:X:X::X/<0-128>   Specify the IPv6 prefix
ASA1(config)# failover interface ip LAN-FAILOVER 10.1.1.1 255.255.255.252 standby 10.1.1.2
ASA1(config)# failover key ?

configure mode commands/options:
  0     Specifies an UNENCRYPTED password will follow
  8     Specifies an ENCRYPTED password will follow
  WORD  Failover shared secret
  hex   Enter 32-character key in hexadecimal format
ASA1(config)# failover key cisco
ASA1(config)# failover link ?

configure mode commands/options:
  WORD  Specify the interface name
ASA1(config)# failover link STATEFUL-FAILOVER ?

configure mode commands/options:
  WORD  Specify physical or sub interface
  <cr>
ASA1(config)# failover link STATEFUL-FAILOVER gigabitethernet5
INFO: Non-failover interface config is cleared on GigabitEthernet5 and its sub-interfaces
ASA1(config)# failover interface ip ?

configure mode commands/options:
Current available interface(s):
  LAN-FAILOVER       Name of interface GigabitEthernet4
  STATEFUL-FAILOVER  Name of interface GigabitEthernet5
ASA1(config)# failover interface ip STATEFUL-FAILOVER ?

configure mode commands/options:
  Hostname or A.B.C.D  Specify the IP address
  X:X:X:X::X/<0-128>   Specify the IPv6 prefix
ASA1(config)# failover interface ip STATEFUL-FAILOVER 10.2.2.1 255.255.255.252 standby 10.2.2.2
ASA1(config)# failover replication ?

configure mode commands/options:
  http  Enable HTTP (port 80) connection replication
ASA1(config)# failover replication http
ASA1(config)# failover lan unit ?

configure mode commands/options:
  primary    Configure the unit as primary
  secondary  Configure the unit as secondary
ASA1(config)# failover lan unit primary
ASA1(config)# prompt ?

configure mode commands/options:
  context   Display the context in the session prompt (multimode only)
  domain    Display the domain in the session prompt
  hostname  Display the hostname in the session prompt
  priority  Display the priority in the session prompt
  state     Display the traffic passing state in the session prompt
ASA1(config)# prompt hostname priority state   // THIS COMMAND IS USEFUL TO LET US KNOW WHICH ASA DEVICE WE'RE CURRENTLY AT
ASA1/pri/actNoFailover(config)# failover    // PRIMARY ASA AND ACTIVE FIREWALL. WE ENABLE THE FAILOVER FEATURE BY ISSUING THE failover COMMAND

ASA1/pri/act# show failover
Failover On
Failover unit Primary
Failover LAN Interface: LAN-FAILOVER GigabitEthernet4 (up)
Unit Poll frequency 1 seconds, holdtime 15 seconds
Interface Poll frequency 5 seconds, holdtime 25 seconds
Interface Policy 1
Monitored Interfaces 2 of 60 maximum
failover replication http
Version: Ours 8.4(2), Mate Unknown
Last Failover at: 09:05:24 UTC Nov 2 2013
        This host: Primary - Active
                Active time: 120 (sec)
                  Interface inside (192.168.1.1): Normal (Waiting)
                  Interface outside (100.1.1.1): Normal (Waiting)
        Other host: Secondary - Failed   
                Active time: 0 (sec)
                  Interface inside (192.168.1.2): Unknown (Waiting)
                  Interface outside (100.1.1.2): Unknown (Waiting)

Stateful Failover Logical Update Statistics
        Link : STATEFUL-FAILOVER GigabitEthernet5 (up)
        Stateful Obj    xmit       xerr       rcv        rerr
        General         0          0          0          0
        sys cmd         0          0          0          0
        up time         0          0          0          0
        RPC services    0          0          0          0
        TCP conn        0          0          0          0
        UDP conn        0          0          0          0
        ARP tbl         0          0          0          0
        Xlate_Timeout   0          0          0          0
        IPv6 ND tbl     0          0          0          0
        VPN IKEv1 SA    0          0          0          0
        VPN IKEv1 P2    0          0          0          0
        VPN IKEv2 SA    0          0          0          0
        VPN IKEv2 P2    0          0          0          0
        VPN CTCP upd    0          0          0          0
        VPN SDI upd     0          0          0          0
        VPN DHCP upd    0          0          0          0
        SIP Session     0          0          0          0
        Route Session   0          0          0          0
        User-Identity   0          0          0          0

        Logical Update Queue Information
                        Cur     Max     Total
        Recv Q:         0       0       0
        Xmit Q:         0       0       0
ASA1/pri/act# .

        No Response from Mate   // WE HAVEN'T CONFIGURED ASA2 YET


----


ASA2# show interface ip brief
Interface                  IP-Address      OK? Method Status                Protocol
GigabitEthernet0           unassigned      YES unset  administratively down up
GigabitEthernet1           unassigned      YES unset  administratively down up
GigabitEthernet2           unassigned      YES unset  administratively down up
GigabitEthernet3           unassigned      YES unset  administratively down up
GigabitEthernet4           unassigned      YES unset  administratively down up
GigabitEthernet5           unassigned      YES unset  administratively down up
ASA2# configure terminal
ASA2(config)# interface gigabitethernet4    // LAN-BASED FAILOVER
ASA2(config-if)# no shutdown
ASA2(config-if)# interface gigabitethernet5    // STATEFUL FAILOVER
ASA2(config-if)# no shutdown
ASA2(config-if)# exit
ASA2(config)# failover lan interface LAN-FAILOVER gigabitethernet4   // WE JUST NEED TO CONFIGURE THE LAN-BASED FAILOVER INTERFACE ON ASA2
INFO: Non-failover interface config is cleared on GigabitEthernet4 and its sub-interfaces
ASA2(config)# failover interface ip LAN-FAILOVER 10.1.1.1 255.255.255.252 standby 10.1.1.2
ASA2(config)# failover key cisco
ASA2(config)# failover lan unit secondary
ASA2(config)# failover
ASA2(config)# .

        Detected an Active mate
Beginning configuration replication from mate.
ERROR: Password recovery was not changed, unable to access
the configuration register.
COREDUMP UPDATE: open message queue fail: No such file or directory/2
Crashinfo is NOT enabled on Full Distribution Environment
End configuration replication from mate.

INFO: Issuing "tls-proxy maximum-sessions 10000" command due to license change

INFO: "tls-proxy maximum-sessions" config is changed, please save the running-config before system

reboot

ASA1/sec/stby(config)# show failover   // HOSTNAME IS RETAINED, ASA2 IS ACTING AS SECONDARY FIREWALL AND CURRENTLY IN STANDBY MODE
Failover On
Failover unit Secondary
Failover LAN Interface: LAN-FAILOVER GigabitEthernet4 (up)
Unit Poll frequency 1 seconds, holdtime 15 seconds
Interface Poll frequency 5 seconds, holdtime 25 seconds
Interface Policy 1
Monitored Interfaces 2 of 60 maximum
failover replication http
Version: Ours 8.4(2), Mate 8.4(2)
Last Failover at: 08:31:23 UTC Nov 2 2013
        This host: Secondary - Standby Ready
                Active time: 0 (sec)
                  Interface inside (192.168.1.2): Normal (Monitored)
                  Interface outside (100.1.1.2): Unknown (Waiting)
        Other host: Primary - Active
                Active time: 618 (sec)
                  Interface inside (192.168.1.1): Normal (Monitored)
                  Interface outside (100.1.1.1): Unknown (Waiting)

Stateful Failover Logical Update Statistics
        Link : STATEFUL-FAILOVER GigabitEthernet5 (up)
        Stateful Obj    xmit       xerr       rcv        rerr
        General         17         0          20         0
        sys cmd         17         0          17         0
        up time         0          0          0          0
        RPC services    0          0          0          0
        TCP conn        0          0          0          0
        UDP conn        0          0          0          0
        ARP tbl         0          0          2          0
        Xlate_Timeout   0          0          0          0
        IPv6 ND tbl     0          0          0          0
        VPN IKEv1 SA    0          0          0          0
        VPN IKEv1 P2    0          0          0          0
        VPN IKEv2 SA    0          0          0          0
        VPN IKEv2 P2    0          0          0          0
        VPN CTCP upd    0          0          0          0
        VPN SDI upd     0          0          0          0
        VPN DHCP upd    0          0          0          0
        SIP Session     0          0          0          0
        Route Session   0          0          0          0
        User-Identity   0          0          1          0

        Logical Update Queue Information
                        Cur     Max     Total
        Recv Q:         0       18      335
        Xmit Q:         0       1       18
ASA1/sec/stby(config)#


----


ASA1/pri/act# Beginning configuration replication: Sending to mate.   // AFTER ASA2 WAS SUCCESSFULLY CONFIGURED, ASA1 SYNCHRONIZED ITS RUNNING CONFIG WITH ASA2

INFO: Issuing "tls-proxy maximum-sessions 10000" command due to license change

INFO: "tls-proxy maximum-sessions" config is changed, please save the running-config before system

reboot
End Configuration Replication to mate

ASA1/pri/act# show failover
Failover On
Failover unit Primary
Failover LAN Interface: LAN-FAILOVER GigabitEthernet4 (up)
Unit Poll frequency 1 seconds, holdtime 15 seconds
Interface Poll frequency 5 seconds, holdtime 25 seconds
Interface Policy 1
Monitored Interfaces 2 of 60 maximum
failover replication http
Version: Ours 8.4(2), Mate 8.4(2)
Last Failover at: 09:05:24 UTC Nov 2 2013
        This host: Primary - Active
                Active time: 604 (sec)
                  Interface inside (192.168.1.1): Normal (Monitored)
                  Interface outside (100.1.1.1): Unknown (Waiting)
        Other host: Secondary - Standby Ready
                Active time: 0 (sec)
                  Interface inside (192.168.1.2): Normal (Monitored)
                  Interface outside (100.1.1.2): Unknown (Waiting)

Stateful Failover Logical Update Statistics
        Link : STATEFUL-FAILOVER GigabitEthernet5 (up)
        Stateful Obj    xmit       xerr       rcv        rerr
        General         18         0          15         0
        sys cmd         15         0          15         0
        up time         0          0          0          0
        RPC services    0          0          0          0
        TCP conn        0          0          0          0
        UDP conn        0          0          0          0
        ARP tbl         2          0          0          0
        Xlate_Timeout   0          0          0          0
        IPv6 ND tbl     0          0          0          0
        VPN IKEv1 SA    0          0          0          0
        VPN IKEv1 P2    0          0          0          0
        VPN IKEv2 SA    0          0          0          0
        VPN IKEv2 P2    0          0          0          0
        VPN CTCP upd    0          0          0          0
        VPN SDI upd     0          0          0          0
        VPN DHCP upd    0          0          0          0
        SIP Session     0          0          0          0
        Route Session   0          0          0          0
        User-Identity   1          0          0          0

        Logical Update Queue Information
                        Cur     Max     Total
        Recv Q:         0       12      144
        Xmit Q:         0       29      190
ASA1/pri/act# configure terminal
ASA1/pri/act(config)# no failover ?

configure mode commands/options:
  interface         Configure the IP address to be used for failover and/or
                    stateful update information
  interface-policy  Set the policy for failover due to interface failures
  key               Configure the failover shared secret or key
  lan               Specify the unit as primary or secondary or configure the
                    interface and vlan to be used for failover communication
  link              Configure the interface and vlan to be used as a link for
                    stateful update information
  mac               Specify the virtual mac address for a physical interface
  polltime          Configure failover poll interval
  replication       Enable HTTP (port 80) connection replication
  timeout           Specify the failover reconnect timeout value for
                    asymmetrically routed sessions
  <cr>

exec mode commands/options:
  active  Make this system to be the active unit of the failover pair
ASA1/pri/act(config)# no failover active   // WE FORCE FAILOVER TO ASA2
ASA1/pri/act(config)# Waiting for the earlier webvpn instance to terminate...
Previous instance shut down. Starting a new one.

        Switching to Standby

ASA1/pri/stby(config)# show failover
Failover On
Failover unit Primary
Failover LAN Interface: LAN-FAILOVER GigabitEthernet4 (up)
Unit Poll frequency 1 seconds, holdtime 15 seconds
Interface Poll frequency 5 seconds, holdtime 25 seconds
Interface Policy 1
Monitored Interfaces 2 of 60 maximum
failover replication http
Version: Ours 8.4(2), Mate 8.4(2)
Last Failover at: 09:18:41 UTC Nov 2 2013
        This host: Primary - Standby Ready
                Active time: 796 (sec)
                  Interface inside (192.168.1.2): Normal (Waiting)
                  Interface outside (100.1.1.2): Unknown (Waiting)
        Other host: Secondary - Active
                Active time: 10 (sec)
                  Interface inside (192.168.1.1): Normal (Waiting)
                  Interface outside (100.1.1.1): Unknown (Waiting)

Stateful Failover Logical Update Statistics
        Link : STATEFUL-FAILOVER GigabitEthernet5 (up)
        Stateful Obj    xmit       xerr       rcv        rerr
        General         45         0          42         0
        sys cmd         42         0          42         0
        up time         0          0          0          0
        RPC services    0          0          0          0
        TCP conn        0          0          0          0
        UDP conn        0          0          0          0
        ARP tbl         2          0          0          0
        Xlate_Timeout   0          0          0          0
        IPv6 ND tbl     0          0          0          0
        VPN IKEv1 SA    0          0          0          0
        VPN IKEv1 P2    0          0          0          0
        VPN IKEv2 SA    0          0          0          0
        VPN IKEv2 P2    0          0          0          0
        VPN CTCP upd    0          0          0          0
        VPN SDI upd     0          0          0          0
        VPN DHCP upd    0          0          0          0
        SIP Session     0          0          0          0
        Route Session   0          0          0          0
        User-Identity   1          0          0          0

        Logical Update Queue Information
                        Cur     Max     Total
        Recv Q:         0       12      395
        Xmit Q:         0       29      428


----


ASA1/sec/stby(config)# Waiting for the earlier webvpn instance to terminate...
Previous instance shut down. Starting a new one.

        Switching to Active    // ASA2 TOOK OVER AND BECAME THE ACTIVE FIREWALL

ASA1/sec/act(config)# show failover
Failover On
Failover unit Secondary
Failover LAN Interface: LAN-FAILOVER GigabitEthernet4 (up)
Unit Poll frequency 1 seconds, holdtime 15 seconds
Interface Poll frequency 5 seconds, holdtime 25 seconds
Interface Policy 1
Monitored Interfaces 2 of 60 maximum
failover replication http
Version: Ours 8.4(2), Mate 8.4(2)
Last Failover at: 09:18:38 UTC Nov 2 2013
        This host: Secondary - Active
                Active time: 29 (sec)
                  Interface inside (192.168.1.1): Normal (Monitored)
                  Interface outside (100.1.1.1): Unknown (Waiting)
        Other host: Primary - Standby Ready
                Active time: 796 (sec)
                  Interface inside (192.168.1.2): Normal (Monitored)
                  Interface outside (100.1.1.2): Unknown (Waiting)

Stateful Failover Logical Update Statistics
        Link : STATEFUL-FAILOVER GigabitEthernet5 (up)
        Stateful Obj    xmit       xerr       rcv        rerr
        General         45         0          48         0
        sys cmd         45         0          45         0
        up time         0          0          0          0
        RPC services    0          0          0          0
        TCP conn        0          0          0          0
        UDP conn        0          0          0          0
        ARP tbl         0          0          2          0
        Xlate_Timeout   0          0          0          0
        IPv6 ND tbl     0          0          0          0
        VPN IKEv1 SA    0          0          0          0
        VPN IKEv1 P2    0          0          0          0
        VPN IKEv2 SA    0          0          0          0
        VPN IKEv2 P2    0          0          0          0
        VPN CTCP upd    0          0          0          0
        VPN SDI upd     0          0          0          0
        VPN DHCP upd    0          0          0          0
        SIP Session     0          0          0          0
        Route Session   0          0          0          0
        User-Identity   0          0          1          0

        Logical Update Queue Information
                        Cur     Max     Total
        Recv Q:         0       18      776
        Xmit Q:         0       1       88


----


ASA1/sec/act# write memory    // WHENEVER a write memory IS ISSUED ON THE ACTIVE FIREWALL, THE SAME IS DONE ON THE STANDBY FIREWALL
Building configuration...
Cryptochecksum: f1122c95 641fe674 f46d69ff c66b305e

2668 bytes copied in 2.20 secs (1334 bytes/sec)
[OK]


ASA1/pri/stby# Cryptochecksum: d854c471 4c772f39 6db68042 8fceddf0

2665 bytes copied in 1.250 secs (2665 bytes/sec)


Here are some useful show commands and configuring the active-standby failover using ASDM.

ASA1/sec/act# show failover ?

  descriptor  Show failover interface descriptors. Two numbers are shown for
              each interface. When exchanging information regarding a
              particular interface, this unit uses the first number in messages
              it sends to its peer. And it expects the second number in
              messages it receives from its peer. For trouble shooting, collect
              the show output from both units and verify that the numbers
              match.
  exec        Show failover command execution information
  history     Show failover switching history
  interface   Show failover command interface information
  state       Show failover internal state information
  statistics  Show failover command interface statistics information
  |           Output modifiers
  <cr>

ASA1/sec/act# show failover history
==========================================================================
From State                 To State                   Reason
==========================================================================
08:31:23 UTC Nov 2 2013
Not Detected               Disabled                   No Error

09:12:52 UTC Nov 2 2013
Disabled                   Negotiation                Set by the config command

09:12:57 UTC Nov 2 2013
Negotiation                Cold Standby               Detected an Active mate

09:12:58 UTC Nov 2 2013
Cold Standby               Sync Config                Detected an Active mate

09:13:24 UTC Nov 2 2013
Sync Config                Sync File System           Detected an Active mate

09:13:24 UTC Nov 2 2013
Sync File System           Bulk Sync                  Detected an Active mate

09:13:38 UTC Nov 2 2013
Bulk Sync                  Standby Ready              Detected an Active mate

09:18:35 UTC Nov 2 2013
Standby Ready              Just Active                Other unit wants me Active

09:18:38 UTC Nov 2 2013
Just Active                Active Drain               Other unit wants me Active

09:18:38 UTC Nov 2 2013
Active Drain               Active Applying Config     Other unit wants me Active

09:18:38 UTC Nov 2 2013
Active Applying Config     Active Config Applied      Other unit wants me Active

09:18:38 UTC Nov 2 2013
Active Config Applied      Active                     Other unit wants me Active

==========================================================================

ASA1/sec/act# show failover interface
        interface LAN-FAILOVER GigabitEthernet4
                System IP Address: 10.1.1.1 255.255.255.252
                My IP Address    : 10.1.1.2
                Other IP Address : 10.1.1.1
        interface STATEFUL-FAILOVER GigabitEthernet5
                System IP Address: 10.2.2.1 255.255.255.252
                My IP Address    : 10.2.2.2
                Other IP Address : 10.2.2.1

ASA1/sec/act# show failover state

               State          Last Failure Reason      Date/Time
This host  -   Secondary
               Active         None
Other host -   Primary
               Standby Ready  None

====Configuration State===
        Sync Done - STANDBY
====Communication State===
        Mac set

ASA1/sec/act# show failover statistics
        tx:1488
        rx:1352

Using Transparent Firewall Mode on an ASA

An ASA can be configured to operate in transparent firewall mode, such that it appears to operate as a Layer 2 device, without becoming a router hop or a gateway to its connected networks. This is also knwon as a Layer 2 firewall or a stealth firewall, because the ASA's interfaces have no assigned IP addresses and cannot be detected or manipulated. Only a single management address is used for traffic sourced by the transparent firewall itself or destined for a management session.

As a Layer 2 device, an ASA in transparent firewall mode can be installed or wedged into an existing network, separating the inside and outside without changing any IP address. This is commonly called a "bump-in-the-wire" because the ASA doesn't break or segment the IP subnet along a wire but instead more or less becomes part of the wire. This makes a new installation straigthforward.

You can also think of a transparent mode firewall as a type of transparent bridge, where packets are bridged from one interface to another based only on their MAC addresses. The ASA must maintain a MAC address table of the source address learned in each received packet, along with the interface on which the packet arrived. Once a MAC address has been learned, the ASA is able to forward a packet to that address by knowing the location or the egress interface where that same address has been active before.

Comparison of the Routed and Transparent Firewall Modes

Routed Firewall Mode

* Use only when IP packets are to be inspected.

* Network readdressing is necessary across the ASA.

* All interfaces can be used.

* All ASA interfaces are available.


Transparent Firewall Mode

* Use when non-IP packets must be forwarded.

* Network readdressing is not necessary.

* Only 2-4 interfaces can be used per bridge group.

* The following features are not available:

   - Dynamic routing protocols
    - Dynamic DNS
    - DHCP Relay
    - Multicast IP routing
    - Quality of service
    - VPN termination for transit traffic


Configuring Transparent Firewall Mode

Before you begin configuring transparent firewall mode, you should verify which mode is currently in use. You can do that with the show firewall EXEC command. The ASA runs in default routed (or "router") mode.

ciscoasa# show firewall
Firewall mode: Router


You can enable transparent firewall mode with the following command:

ciscoasa(config)# firewall ?

configure mode commands/options:
  transparent  Switch to transparent mode
ciscoasa(config)# firewall transparent
ERROR: Password recovery was not changed, unable to access
the configuration register.
COREDUMP UPDATE: open message queue fail: No such file or directory/2


Transparent firewall mode begins immediately and doesn't require a reload; however, because transparent and routed firewall modes uses different approaches to network security, the running configuration will be cleared as soon as transparent mode begins. The idea is to enter transparent firewall mode and build an appropriate configuration from scratch.

For that reason, you should save the routed firewall mode running configuration to flash memory or to an external server before enabling transparent firewall mdoe. That way, you will have a copy of the configuration in case you need to revert to routed firewall mode or refer to some portion of that configuration. Because the configuration is cleared, ASDM does not offer any way to change the firewall mode.

Next, you will need to set aside ASA interfaces and configure them for transparent firewall use. For ASA release 8.4(1) or later, you can configure up to four interfaces as part of a bridge group. With earlier releases, you must use exactly two interfaces - one interface will face the "outside," less secure part of the network, while the other will face the "inside," more secure area.

Configure the interfaces exactly as you would with routed firewall mode, with the exception of any IP addresses, by supplying the following parameters:

* Interface speed and duplex mode

* Interface name

* Security level

* Bridge group number (ASA release 8.4(1) and later)


In ASDM, navigate to Configuration > Device Setup > Interfaces, select an interface, and click Edit.

If you choose to configure interfaces with the CLI instead, you can use the nameif, security-level, and bridge-group interface configuration commands.

ciscoasa(config)# interface gigabitethernet0
ciscoasa(config-if)# nameif inside
INFO: Security level for "inside" set to 100 by default.
ciscoasa(config-if)# bridge-group ?

interface mode commands/options:
  <1-100>  Group number of this interface
ciscoasa(config-if)# bridge-group 1
ciscoasa(config-if)# no shutdown
ciscoasa(config-if)# interface gigabitethernet1
ciscoasa(config-if)# nameif outside
INFO: Security level for "outside" set to 0 by default.
ciscoasa(config-if)# bridge-group 1
ciscoasa(config-if)# no shutdown


Next, assign a single IP address to each bridge group as a whole. This address will be used for management traffic, such as Telnet, SSH, HTTP, SNMP, syslog, TFTP, FTP, and so on. If you configure the ASA for multiple context mode, you should configure one IP address for each bridge group on each security context, including the admin context. From the interface list in ASDM, select Add and choose Bridge Virtual Interface (BVI).

ciscoasa(config-if)# interface ?

configure mode commands/options:
  BVI              Bridge-Group Virtual Interface
  GigabitEthernet  GigabitEthernet IEEE 802.3z
  Port-channel     Ethernet Channel of interfaces
  Redundant        Redundant Interface
  <cr>
ciscoasa(config-if)# interface bvi ?

configure mode commands/options:
  <1-100>  BVI interface number
ciscoasa(config-if)# interface bvi 1
ciscoasa(config-if)# ip address 192.168.1.1 255.255.255.0

Detecting and Filtering Botnet Traffic on an ASA

In a botnet attack, hosts on the private side of an ASA becomes infected with malware. Each of the infected hosts tries to contact a botnet control server located somewhere on the public Internet to receive further instructions. The control server is then able to remotely control many infected hosts and align them in a coordinated attack against other resources.

Because the infected hosts are located on a secure side of the ASA, they are likely to be free to open outbound connections just like any other protected host. You can leverage the Cisco ASA Botnet Traffic Filter feature to detect botnet activity and prevent infected hosts from contacting their control servers.

When the Botnet Traffic Filter is enabled, an ASA maintains two reputation databases:

* A dynamic SensorBase database that is downloaded periodically from Cisco, which contains information about known botnet control servers.

* A static database that you can populate, which can contain a "whitelist" of known good IP addresses and domain names or a "blacklist" of known bad servers.

The Botnet Traffic Filter feature is dependent upon four things:

* A Botnet Traffic Filter license purchased from Cisco and installed on the ASA

* A DNS server, which the ASA uses to lookup names and addresses in the static database

* Botnet Traffic Filter DNS snooping, which enables the ASA to intercept DNS queries from infected hosts and match against hostnames it finds in the databases

* Live connectivity to the Internet, so that the Botnet Traffic Filter feature can communicate with Cisco

Before you begin configuring Botnet Traffic Filtering, verify that the feature license has been enabled. You can use the show version command to see a list of ASA features and their license status. Make sure Botnet Traffic Filter is listed as Enabled

ciscoasa# show version

Cisco Adaptive Security Appliance Software Version 8.4(2)

Compiled on Wed 15-Jun-11 18:17 by builders
System image file is "Unknown, monitor mode tftp booted image"
Config file at boot was "startup-config"

ciscoasa up 11 mins 39 secs

Hardware:   ASA 5520, 1024 MB RAM, CPU Pentium II 1000 MHz
Internal ATA Compact Flash, 256MB
BIOS Flash unknown @ 0x0, 0KB


 0: Ext: GigabitEthernet0    : address is 00ab.cd92.5200, irq 0
 1: Ext: GigabitEthernet1    : address is 0000.abf1.d701, irq 0
 2: Ext: GigabitEthernet2    : address is 0000.ab9a.0e02, irq 0
 3: Ext: GigabitEthernet3    : address is 0000.ab64.2f03, irq 0
 4: Ext: GigabitEthernet4    : address is 0000.ab84.7804, irq 0
 5: Ext: GigabitEthernet5    : address is 0000.abfa.5105, irq 0

Licensed features for this platform:
Maximum Physical Interfaces       : Unlimited      perpetual
Maximum VLANs                     : 100            perpetual
Inside Hosts                      : Unlimited      perpetual
Failover                          : Active/Active  perpetual
VPN-DES                           : Enabled        perpetual
VPN-3DES-AES                      : Enabled        perpetual
Security Contexts                 : 5              perpetual
GTP/GPRS                          : Disabled       perpetual
AnyConnect Premium Peers          : 25             perpetual
AnyConnect Essentials             : Disabled       perpetual
Other VPN Peers                   : 5000           perpetual
Total VPN Peers                   : 0              perpetual
Shared License                    : Enabled        perpetual
AnyConnect for Mobile             : Disabled       perpetual
AnyConnect for Cisco VPN Phone    : Disabled       perpetual
Advanced Endpoint Assessment      : Enabled        perpetual
UC Phone Proxy Sessions           : 10             perpetual
Total UC Proxy Sessions           : 10             perpetual
Botnet Traffic Filter             : Enabled        perpetual
Intercompany Media Engine         : Enabled        perpetual

This platform has an ASA 5520 VPN Plus license.


Use the following steps to configure botnet traffic filtering:

Step 1: Configure the dynamic database.

Step 2: Configure the static database.

Step 3: Enable DNS snooping.

Step 4: Enable the Botnet Traffic Filter.

ciscoasa(config)# dynamic-filter ?

configure mode commands/options:
  ambiguous-is-black  Handle (ambiguous) greylist matched traffic as blacklist
                      for Dynamic Filter drop
  blacklist           Configure Dynamic Filter blacklist
  drop                Enable traffic drop based on Dynamic Filter traffic
                      classification
  enable              Enable Dynamic Filter classification
  updater-client      Configure Dynamic Filter updater client
  use-database        Use Dynamic Filter data downloaded from updater-server
  whitelist           Configure Dynamic Filter whitelist

exec mode commands/options:
  database  Dynamic Filter data commands
ciscoasa(config)# dynamic-filter updater-client ?

configure mode commands/options:
  enable  Enable Dynamic Filter updater client
ciscoasa(config)# dynamic-filter updater-client enable
WARNING: Can't resolve update-manifests.ironport.com, make sure dns nameserver is configured  // CISCO'S DYNAMIC DATABASE UPDATE
ciscoasa(config)# dynamic-filter use-database
ciscoasa(config)# dns ?   // CONFIGURE DNS AS PER ERROR GIVEN

configure mode commands/options:
  domain-lookup       Enable/Disable DNS host-to-address translation
  expire-entry-timer  Specify DNS entry expire timer
  name-server         Specify DNS servers
  poll-timer          Specify dns update interval
  retries             Configure DNS retries
  server-group        Configure a DNS server group
  timeout             Configure DNS query timeout
ciscoasa(config)# dns domain-lookup outside
ciscoasa(config)# dns server-group MY-DNS-GROUP
ciscoasa(config-dns-server-group)# ?
DNS server group commands:
  domain-name  Domain name to append to DNS queries for this server group
  name-server  Specify DNS servers
  no           Remove a server-group command or set to its default
  retries      DNS retries
  timeout      DNS query timeout
ciscoasa(config-dns-server-group)# name-server 4.2.2.2
ciscoasa(config)# dynamic-filter blacklist
ciscoasa(config-llist)# ?

Dynamic Filter list configuration
  address  Add IP address to local list
  name     Add domain name to local list
  no       Negate a command
ciscoasa(config-llist)# name ?

dynamic-filter-list mode commands/options:
  WORD < 256 char  Enter domain name

configure mode commands/options:
  A.B.C.D     The IPv4 address of the host/network being named
  X:X:X:X::X  The IPv6 address of the host/network being named
ciscoasa(config-llist)# name www.badsite.com
ciscoasa(config-llist)#exit
ciscoasa(config)# dynamic-filter whitelist
ciscoasa(config-llist)# name www.goodsite.com
ciscoasa(config-llist)#exit
ciscoasa(config)# policy-map ?

configure mode commands/options:
  type            Specifies the type of policy-map
Policy-map names:
  global_policy
  WORD < 41 char  New policy-map name
ciscoasa(config-pmap)# policy-map global_policy
ciscoasa(config-pmap)# class ?

mpf-policy-map mode commands/options:
  WORD            class-map name
  class-default   System default class matching otherwise unclassified packets

configure mode commands/options:
  WORD < 41 char  class-map name
  type            Specifies the type of class-map
ciscoasa(config-pmap)# class inspection_default
ciscoasa(config-pmap-c)# ?

MPF policy-map class configuration commands:
  exit             Exit from MPF class action configuration mode
  help             Help for MPF policy-map class/match submode commands
  no               Negate or set default values of a command
  police           Rate limit traffic for this class
  priority         Strict scheduling priority for this class
  quit             Exit from MPF class action configuration mode
  service-policy   Configure QoS Service Policy
  set              Set connection values
  shape            Traffic Shaping
  user-statistics  configure user statistics for identity firewall
  <cr>
  csc              Content Security and Control service module
  flow-export      Configure filters for NetFlow events
  inspect          Protocol inspection services
  ips              Intrusion prevention services
ciscoasa(config-pmap-c)# inspect ?

mpf-policy-map-class mode commands/options:
  ctiqbe
  dcerpc
  dns
  esmtp
  ftp
  gtp
  h323
  http
  icmp
  ils
  im
  ip-options
  ipsec-pass-thru
  ipv6
  mgcp
  mmp
  netbios
  pptp
  rsh
  rtsp
  sip
  skinny
  snmp
ciscoasa(config-pmap-c)# inspect dns ?

mpf-policy-map-class mode commands/options:
  WORD < 41 char        Optional DNS type policy-map name
  dynamic-filter-snoop  Enable DNS snooping for Dynamic Filter
  <cr>
ciscoasa(config-pmap-c)# inspect dns preset_dns_map ?

mpf-policy-map-class mode commands/options:
  dynamic-filter-snoop  Enable DNS snooping for Dynamic Filter
  <cr>
ciscoasa(config-pmap-c)# inspect dns preset_dns_map dynamic-filter-snoop
ciscoasa(config-pmap-c)# exit
ciscoasa(config-pmap)# exit
ciscoasa(config)# dynamic-filter enable ?

configure mode commands/options:
  classify-list  Set the access-list for classification
  interface      Enable classification on an interface
  <cr>
ciscoasa(config)# dynamic-filter enable interface ?

configure mode commands/options:
Current available interface(s):
  inside  Name of interface GigabitEthernet0
  outside Name of interface GigabitEthernet1
ciscoasa(config)# dynamic-filter enable interface outside?

configure mode commands/options:
  classify-list  Set the access-list for classification
  <cr>
ciscoasa(config)# dynamic-filter enable interface outside classify-list ?

configure mode commands/options:
  WORD  Specify the name of an access-list
ciscoasa(config)# dynamic-filter enable interface outside classify-list BOTNET_ACL
ciscoasa(config)# dynamic-filter drop ?

configure mode commands/options:
  blacklist  Drop traffic matching blacklist
ciscoasa(config)# dynamic-filter drop blacklist ?

configure mode commands/options:
  action-classify-list  Set the access-list for drop
  interface             Enable drop on an interface
  threat-level          Set the threat-level for drop
  <cr>
ciscoasa(config)# dynamic-filter drop blacklist interface ?

configure mode commands/options:
Current available interface(s):
  inside  Name of interface GigabitEthernet0
  outside  Name of interface GigabitEthernet1
ciscoasa(config)# dynamic-filter drop blacklist interface outside ?

configure mode commands/options:
  action-classify-list  Set the access-list for drop
  threat-level          Set the threat-level for drop
  <cr>
ciscoasa(config)# dynamic-filter drop blacklist interface outside action-classify-list ?

configure mode commands/options:
  WORD  Specify the name of an access-list
ciscoasa(config)# dynamic-filter drop blacklist interface outside action-classify-list BOTNET_ACL ?

configure mode commands/options:
  threat-level  Set the threat-level for drop
  <cr>
ciscoasa(config)# dynamic-filter drop blacklist interface outside action-classify-list BOTNET_ACL threat-level ?

configure mode commands/options:
  eq     Threat-level equal to operator
  range  Threat-level range operator
ciscoasa(config)# dynamic-filter drop blacklist interface outside action-classify-list BOTNET_ACL threat-level eq ?

configure mode commands/options:
  high       high threat
  low        Low threat
  moderate   moderate threat
  very-high  Highest threat
  very-low   lowest threat
ciscoasa(config)# dynamic-filter drop blacklist interface outside action-classify-list BOTNET_ACL threat-level eq very-high