Saturday, September 5, 2020

Enabling coredump on a Cisco ASA Firewall

Here's a nice link in configuring a coredump in a Cisco ASA Firewall. This feature takes a snapshot of the ASA memory when a system crash occur, which can give useful information to Cisco TAC engineer in their troubleshooting.

 

LAB-ASA5515x# show coredump filesystem  

 

'disk0:' has no coredump filesystem

LAB-ASA5515x# conf t

LAB-ASA5515x(config)# coredump ?    

 

configure mode commands/options:

  enable  Enable coredump generation to filesystem

LAB-ASA5515x(config)# coredump enable

 

WARNING: Enabling coredump on an ASA5515 platform will delay the reload of

the system by up to 30 minutes in the event of software forced reload.

The exact time depends on the size of the coredump generated.

 

Proceed with coredump filesystem allocation of 1000 MB

on 'disk0:' (Note this may take a while) ? [confirm]

filesys_image created ok: disk0:coredumpfsysimage.bin

 

Making coredump file system image!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

<OUTPUT TRUNCATED>


!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Coredump file system image created & mounted successfully

 

/dev/loop0 on /mnt/disk0/coredumpfsys type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)

 

 

LAB-ASA5515x(config)# dir

 

Directory of disk0:/

 

95     -rwx  111550464    06:02:40 Oct 15 2019  asa984-10-smp-k8.bin

96     -rwx  33696792     06:04:16 Oct 15 2019  asdm-7122.bin

11     drwx  4096         06:08:18 Oct 15 2019  log

22     drwx  4096         06:08:58 Oct 15 2019  crypto_archive

25     drwx  4096         06:09:04 Oct 15 2019  coredumpinfo

98     -rwx  4799         05:14:28 Oct 26 2019  oldconfig_2019Oct26_0514.cfg

23     drwx  4096         05:25:12 Nov 24 2019  snmp

104    -rwx  72771616     04:22:02 May 20 2020  anyconnect-win-4.8.03052-webdeploy-k9.pkg

105    -rwx  111624192    04:22:42 May 20 2020  asa984-20-smp-k8.bin

110    -rwx  1048576000   03:28:09 Jul 29 2020  coredumpfsysimage.bin

1      drwx  16384        03:27:39 Jul 29 2020  coredumpfsys

 

6 file(s) total size: 1378223863 bytes

7994437632 bytes total (6615339008 bytes free/82% free)

 

 

LAB-ASA5515x(config)# no coredump enable

LAB-ASA5515x(config)# dir

 

Directory of disk0:/

 

95     -rwx  111550464    06:02:40 Oct 15 2019  asa984-10-smp-k8.bin

96     -rwx  33696792     06:04:16 Oct 15 2019  asdm-7122.bin

11     drwx  4096         06:08:18 Oct 15 2019  log

22     drwx  4096         06:08:58 Oct 15 2019  crypto_archive

25     drwx  4096         06:09:04 Oct 15 2019  coredumpinfo

98     -rwx  4799         05:14:28 Oct 26 2019  oldconfig_2019Oct26_0514.cfg

23     drwx  4096         05:25:12 Nov 24 2019  snmp

104    -rwx  72771616     04:22:02 May 20 2020  anyconnect-win-4.8.03052-webdeploy-k9.pkg

105    -rwx  111624192    04:22:42 May 20 2020  asa984-20-smp-k8.bin

110    -rwx  1048576000   03:28:09 Jul 29 2020  coredumpfsysimage.bin

1      drwx  16384        03:27:39 Jul 29 2020  coredumpfsys

 

6 file(s) total size: 1378223863 bytes

7994437632 bytes total (6615339008 bytes free/82% free)

 

LAB-ASA5515x(config)# delete disk0:/coredumpfsysimage.bin

 

Delete filename [coredumpfsysimage.bin]?

 

Delete disk0:/coredumpfsysimage.bin? [confirm]

 

LAB-ASA5515x(config)# delete disk0:/coredumpfsys        

 

Delete filename [coredumpfsys]?

 

Delete disk0:/coredumpfsys? [confirm]

 

 

%Error deleting disk0:/coredumpfsys (Device or resource busy)

LAB-ASA5515x(config)# delete ?

 

exec mode commands/options:

  /noconfirm  Do not prompt for confirmation

  /recursive  Recursive delete

  /replicate  Execute delete operation on standby unit as well

  disk0:      File to be deleted

  disk1:      File to be deleted

  flash:      File to be deleted

LAB-ASA5515x(config)# delete /recursive ?

 

exec mode commands/options:

  /noconfirm  Do not prompt for confirmation

  /replicate  Execute delete operation on standby unit as well

  disk0:      File to be deleted

  disk1:      File to be deleted

  flash:      File to be deleted

LAB-ASA5515x(config)# delete /recursive disk0:/coredumpfsys

 

Delete filename [coredumpfsys]?

 

Examine files in directory disk0:/coredumpfsys? [confirm]

 

Delete disk0:/coredumpfsys? [confirm]

 

%Error Removing dir disk0:/coredumpfsys (Device or resource busy)

 

 

LAB-ASA5515x(config)# rmdir coredumpfsys

 

Remove directory filename [coredumpfsys]?

 

Delete disk0:/coredumpfsys? [confirm]

 

%Error Removing dir disk0:/coredumpfsys (Device or resource busy)