Whats `/usr/sbin/unix_chkpwd root nullok` during the S3 backups

[Jeeves_]

Hi,

Playing around with S3 backups and I see a lot of `/usr/sbin/unix_chkpwd root nullok` scrolling by. What are they used for? It seems to be combined with S3 only?

 

[Chris]

Hi,
this does not ring a bell..

Can you please share further details, e.g. where you see these messages, what operations are performed when this happens?

Checked the systemd journal of one of my test instances and there I do see unix_chkpwd messages only in relation to authentication failures with the PBS API. But with e.g. password check failed for user (root)

 

[Jeeves_]

I think I found it. This is a test-instance which authenticates as root@pam. It looks like every call reauthenticates against pam, which runs `/usr/sbin/unix_chkpwd root nullok` in turn.

Sounds that it could use some caching, but caching and authentication...

 

[Chris]

I think I found it. This is a test-instance which authenticates as root@pam. It looks like every call reauthenticates against pam, which runs `/usr/sbin/unix_chkpwd root nullok` in turn.

Did you change the pam configuration, these messages do not show up here?

Sounds that it could use some caching, but caching and authentication...

There already is user caching in place, e.g. see [0]. That's why I was wondering what operations are being performed when you see this.

Further, please note that you can use API tokens or PBS relam instead of pam authentication, if that is what you want.


[0] https://git.proxmox.com/?p=proxmox-...97c318efd69c69140c88bf58008f2dfcf;hb=HEAD#l91