Re: ssh / keyless login problem

SA wrote:
[...]
> The first time the script runs after a long delay (ie overnight when the local 
> host is turned off) ssh always asks for a password despite there being a 
> valid key pair on both hosts.  If I kill the script and run it again then it 
> runs without asking for a password (as it should).  My script needs to log in 
> several times and run automatically so password free operation is essential.
>
> I can't see why the first time fails - my only thought is that the remote 
> machine mounts my home directory over NFS and maybe this causes a problem?

NFS should not be a problem, but maybe if your home directory is 
auto-mounted and there is some kind of delay in that process?

> Does anyone have any suggestions as to:
>
> How I might solve this problem?
> How I might diagnose it? (it is hard to repeat it more than once a day)
> How I might stop ssh from asking for a password and return an error instead? 
> (in which case I can get my script to handle this exception with a dummy 
> login).

Set the server to LogLevel DEBUG3 and wait for it to happen again, then 
look in the syslog to see what happened.

> Any other suggestions?

Tell the client to use only pubkey auth ("ssh -o 
PreferredAuthentications=publickey ...") and put a sleep-and-retry or 
two into your script.

--
Darren Tucker (dtucker at zip.com.au)
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.