When an OSPF router connects to two or more different areas, it is called an Area Border Router (ABR). When an OSPF router connects an area to a non-OSPF domain and it imports routing information from other sources into OSPF, it is called an Autonomous System Boundary Router (ASBR).
OSPF routers build a common database of the status of all links in the area by exchanging link-state advertisements (LSA). The routers build their routing tables by computing the shortest path first (SPF) algorithm based on that database. OSPF uses a path cost value, which is based on link bandwidth, as a routing metric. An ASA can support at most two different OSPF process.
For this scenario, we configured the ASA to use OSPF in exchanging routes with routers in Area 0.
ASA(config)# interface gigabitethernet0
ASA(config-if)# nameif outside
INFO: Security level for "outside" set to 0 by default.
ASA(config-if)# ip address 192.168.1.2 255.255.255.0
ASA(config-if)# no shutdown
ASA(config-if)# ospf ?
interface mode commands/options:
authentication Enable authentication
authentication-key Authentication password (key)
cost Interface cost
database-filter Filter OSPF LSA during synchronization and flooding
dead-interval Interval after which a neighbor is declared dead
hello-interval Time between HELLO packets
message-digest-key Message digest authentication password (key)
mtu-ignore Ignores the MTU in DBD packets
network Network type
priority Router priority
retransmit-interval Time between retransmitting lost link state
advertisements
transmit-delay Link state transmit delay
ASA(config-if)# ospf cost ?
interface mode commands/options:
<1-65535> Cost
ASA(config-if)# ospf cost 10
ASA(config-if)# interface gigabitethernet1
ASA(config-if)# nameif inside
INFO: Security level for "inside" set to 100 by default.
ASA(config-if)# ip address 172.16.1.1 255.255.255.0
ASA(config-if)# ospf cost 10
ASA(config-if)# ospf authentication ?
interface mode commands/options:
message-digest Use message-digest authentication
null Use no authentication
<cr>
ASA(config-if)# ospf authentication message-digest
ASA(config-if)# ospf message-digest-key ?
interface mode commands/options:
<1-255> Key ID
ASA(config-if)# ospf message-digest-key 1 ?
interface mode commands/options:
md5 Use MD5 algorithm
ASA(config-if)# ospf message-digest-key 1 md5 cisco
ASA(config-if)#exit
ASA(config)# router ?
configure mode commands/options:
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)
ASA(config)# router ospf ?
configure mode commands/options:
<1-65535> Process ID
ASA(config)# router ospf 1
ASA(config-router)# ?
Router configuration commands:
area OSPF area parameters
compatible OSPF compatibility list
default-information Control distribution of default information
distance Define an administrative distance
exit Exit from router configuration mode
help Interactive help for router subcommands
ignore Do not complain about specific event
log-adj-changes Log changes in adjacency state
neighbor Specify a neighbor router
network Add/remove interfaces to/from routing process
no Negate a command
redistribute Redistribute information from another routing process
router-id router-id for this OSPF process
summary-address Configure IP address summaries
timers Adjust routing timers
ASA(config-router)# network ?
router mode commands/options:
Hostname or A.B.C.D Network address
ASA(config-router)# network 172.16.1.0 ?
router mode commands/options:
A.B.C.D Mask for network address
ASA(config-router)# network 172.16.1.0 255.255.255.0 ?
router mode commands/options:
area Set the OSPF area ID
ASA(config-router)# network 172.16.1.0 255.255.255.0 area ?
router mode commands/options:
<0-18446744073709551615> OSPF area ID as a decimal value
Hostname or A.B.C.D OSPF area ID
ASA(config-router)# network 172.16.1.0 255.255.255.0 area 0
ASA(config-router)# show route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.1.0 255.255.255.0 is directly connected, outside
ASA(config-router)# exit
ASA(config)# route outside 0 0 192.168.1.1
ASA(config)# show route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 192.168.1.1 to network 0.0.0.0
C 192.168.1.0 255.255.255.0 is directly connected, outside
S* 0.0.0.0 0.0.0.0 [1/0] via 192.168.1.1, outside
ASA# debug ospf ?
adj
database-timer
events
flood
lsa-generation
packet
retransmission
spf
tree
<cr>
ASA# debug ospf adj
OSPF adjacency events debugging is on
ASA# debug ospf events
OSPF events debugging is on
ASA# configure terminal
ASA(config)# interface gigabitethernet1
ASA(config-if)# no shutdown
ASA(config-if)#
OSPF: Interface inside going Up
OSPF: Send with youngest Key 1
OSPF: Build router LSA for area 0, router ID 192.168.1.2, seq 0x80000002
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: End of hello processing
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: 2 Way Communication to 172.16.1.2 on inside, state 2WAY
OSPF: Backup seen Event before WAIT timer on inside
OSPF: DR/BDR election on inside
OSPF: Elect BDR 192.168.1.2
OSPF: Elect DR 172.16.1.2
OSPF: Elect BDR 192.168.1.2
OSPF: Elect DR 172.16.1.2
DR: 172.16.1.2 (Id) BDR: 192.168.1.2 (Id)
OSPF: Send DBD to 172.16.1.2 on inside seq 0x1237 opt 0x2 flag 0x7 len 32
OSPF: Send with youngest Key 1
OSPF: End of hello processing
OSPF: Rcv DBD from 172.16.1.2 on inside seq 0x2283 opt 0x52 flag 0x7 len 32 mtu 1500 state EXSTART
OSPF: First DBD and we are not SLAVE
OSPF: Rcv DBD from 172.16.1.2 on inside seq 0x1237 opt 0x52 flag 0x2 len 92 mtu 1500 state EXSTART
OSPF: NBR Negotiation Done. We are the MASTER
OSPF: Send DBD to 172.16.1.2 on inside seq 0x1238 opt 0x2 flag 0x3 len 52
OSPF: Send with youngest Key 1
OSPF: Send with youngest Key 1
OSPF: Database request to 172.16.1.2
OSPF: sent LS REQ packet to 172.16.1.2, length 36
OSPF: Rcv DBD from 172.16.1.2 on inside seq 0x1238 opt 0x52 flag 0x0 len 32 mtu 1500 state EXCHANGE
OSPF: Send DBD to 172.16.1.2 on inside seq 0x1239 opt 0x2 flag 0x1 len 32
OSPF: Send with youngest Key 1
OSPF: Send with youngest Key 1
OSPF: Rcv DBD from 172.16.1.2 on inside seq 0x1239 opt 0x52 flag 0x0 len 32 mtu 1500 state EXCHANGE
OSPF: Exchange Done with 172.16.1.2 on inside
OSPF: Synchronized with 172.16.1.2 on inside, state FULL
OSPF: Send with youngest Key 1
OSPF: Build router LSA for area 0, router ID 192.168.1.2, seq 0x80000003
OSPF: Send with youngest Key 1
OSPF: Send with youngest Key 1
OSPF: Send with youngest Key 1
OSPF: Rcv hello from 172.16.1.2 area 0 from inside 172.16.1.2
OSPF: Neighbor change Event on interface inside
OSPF: DR/BDR election on inside
OSPF: Elect BDR 192.168.1.2
OSPF: Elect DR 172.16.1.2
DR: 172.16.1.2 (Id) BDR: 192.168.1.2 (Id)
OSPF: End of hello processing
ASA(config-if)# no debug ospf
ASA(config-if)# show route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 192.168.1.1 to network 0.0.0.0
C 172.16.1.0 255.255.255.0 is directly connected, inside
O 10.1.10.1 255.255.255.255 [110/75] via 172.16.1.2, 0:00:36, inside
O 10.1.2.0 255.255.255.0 [110/74] via 172.16.1.2, 0:00:36, inside
O 10.1.1.0 255.255.255.0 [110/74] via 172.16.1.2, 0:00:36, inside
O 10.1.5.1 255.255.255.255 [110/75] via 172.16.1.2, 0:00:36, inside
C 192.168.1.0 255.255.255.0 is directly connected, outside
S* 0.0.0.0 0.0.0.0 [1/0] via 192.168.1.1, outside
ASA# show ospf ?
<1-65535> OSPF process id
border-routers Show OSPF border routers
database Show OSPF database
flood-list Show OSPF link state flood lists
interface Show OSPF information for a specific interface
neighbor Show OSPF neighbors
request-list Show OSPF link state request-lists
retransmission-list Show OSPF link state retransmission-lists
summary-address Show OSPF summary addresses
virtual-links Show OSPF virtual links
| Output modifiers
<cr>
ASA# show ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
172.16.1.2 1 FULL/DR 0:00:31 172.16.1.2 inside
ASA# show ospf database
OSPF Router with ID (192.168.1.2) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
10.1.5.1 10.1.5.1 949 0x80000002 0x1a6b 3
10.1.10.1 10.1.10.1 898 0x80000002 0x274d 3
172.16.1.2 172.16.1.2 90 0x80000006 0x1776 5
192.168.1.2 192.168.1.2 88 0x80000003 0x3898 1
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
172.16.1.2 172.16.1.2 89 0x80000001 0x 589
ASA# ping 10.1.5.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.5.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/80/220 ms
ASA# ping 10.1.10.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.10.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/38/100 ms
Hi,
ReplyDeleteI studied again for the Cisco ROUTE and SWITCH since both are prerequisites.
The usual materials I always use are the Cisco Press ARCH Official Cert Guide (OCG) and CBT nuggets video.
Note ARCH 300-320 exam was recently updated. See helpful links:
http://www.cisco.com/c/en/us/training-events/training-certifications/certifications/professional/ccdp.html
https://learningnetwork.cisco.com/thread/95220
https://www.cbtnuggets.com/it-training/cisco-ccdp-642-874-arch