/var/log/btmp - no such file after the NXOS 10.3(4a)M upgrade

[leodlsrt]

Hi,
I have upgraded my Cisco Nexus C93180YC-FX yesterday from NXOS 10.2(6)M to NXOS 10.3(4a)M, but I seem that I have an error when I make "sh logging last 10".

2024 Apr 30 09:39:09 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such
 file or directory - dcos_sshd[15277]
2024 Apr 30 09:39:13 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such
 file or directory - dcos_sshd[15292]
2024 Apr 30 09:39:15 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such
 file or directory - dcos_sshd[15301]
2024 Apr 30 09:39:18 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such
 file or directory - dcos_sshd[15313]
2024 Apr 30 09:39:22 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such
 file or directory - dcos_sshd[15356]
2024 Apr 30 09:39:25 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such
 file or directory - dcos_sshd[15433]
2024 Apr 30 09:41:26 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such
 file or directory - dcos_sshd[15433] (message repeated 1 time)

I don't find any solution on the Cisco forum and doesn't find a bug on the Cisco Search Bug console.

Do you have an idea to resolve it or its a bug of the version? 

Thanks a lot.
Léo

[marce1000]

 - This seems to me a problem of the underlying linux os being used ; wait a bit longer and or after a day it may get resolved after for instance an action from logrotate (settings and actions - such as creating the file again)

 M.

[leodlsrt]

Hi,
After some days, we have the same problem on NXOS 10.3(4a)M...

edge01.par03(config)# sh logging last 5
2024 May  2 22:51:20 edge01.par03 %ETHPORT-5-IF_UP: Interface Ethernet1/12 is up in mode access
2024 May  2 22:51:52 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such file or directory - dcos_sshd[28420]
2024 May  2 22:52:07 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such file or directory - dcos_sshd[28420] (message repeated 1 time)
2024 May  2 22:52:07 edge01.par03 %DAEMON-2-SYSTEM_MSG: fatal: Timeout before authentication for 111.12.45.85 port 51090 - dcos_sshd[27451]
2024 May  2 22:52:38 edge01.par03 %DAEMON-3-SYSTEM_MSG: error: Unable to open the btmp file /var/log/btmp: No such file or directory - dcos_sshd[29010]

Anyone have a solution to patch this or I need to open a bug on the Cisco Platform ? 

Thanks in advance,
Sincerely
Léo

[To_Willem_or_Not_Willem_ · Accepted solution]

failed ssh auth: DAEMON-3-SYSTEM_MSG error Unable to open the btmp file /var/log/btmp dcos_sshd
CSCwh93455  

run bash sudo su

touch /var/log/btmp

chmod 600 /var/log/btmp

[leodlsrt]

Hi,
This solution works perfectly

Thanks a lot.

Léo

[RonF]

Did not work for me.  For one thing, "run bash sudo su" gave me "% Invalid command at '^" marker." pointing at "bash".   "run ?" came up with the alternatives "cid" and "guestshell".  I had to install "guestshell".

After that, I logged in only to find that /var/log/btmp existed as "-rw-r--r-- 1 root root      0 Sep 18 17:44 btmp"  So I tried logging in with a bogus ID only to still see the error.  Then I tried "cd /var/log" and then "chmod 600 btmp", but that didn't help and neither did "chown root:utmp btmp".

What's next?


[root@guestshell log]# ls - la

total 48

drwxr-xr-x  2 root root   180 Sep 18 17:32

drwxrwxrwt 4 root root    80 Sep 18 17:32 .

-rw------- 1 root root      0 Sep 18 17:31 ..

[To_Willem_or_Not_Willem_]

routername# run ?
bash Linux-bash
cid Cisco Interactive Debug shell
guestshell The guest shell Linux-bash

routername# run bash ?
<CR>
LINE The command to execute

routername# run bash sudo su
bash-4.4#
bash-4.4# cd /var/log/


bash-4.4# ls -la | grep btmp
-rw------- 1 root root 10368 Sep 19 04:53 btmp
bash-4.4#

Not sure if is maybe a role/permission thing on your end. But this looks like its working for me with a tacacs role 15.
But there is a difference in the filename list for me between run bash, and run guestshell. (With guestshell I also see another, but different /var/log/btmp file)

[RonF]

This solution does not work for me.  When I run "run bash sudo su" I get an error.  It turns out that "bash" isn't an option; only "cid" and "guestshell" is.  I did try this with "guestshell" but the error still recurs.  I had to install guestshell, and when I did it created /var/log and its contents, including /var/log/btmp with 644 and root:root.  I tried chmod 600 but that didn't work.