Re: how to check the server can be connected or not

[Dom <toyer@rpdom.net>]

On 03/02/12 15:05, Jon Dowland wrote:
> On 03/02/12 09:55, lina wrote:
> > On Friday 03,February,2012 05:32 PM, Jon Dowland wrote:
> > > while true; do
> > > ssh server && break
> > > done
> > Thanks for both of you,
> >
> > the two ways once ssh server,
> > it stayed in server and won't come back and proceed the rest.
>
> I don't fully understand your follow-up, but to explain my solution: it
> will loop as long as the ssh process returns an error code. So if the
> ssh session connects successfully, upon ending the session, it will
> return a success code and the loop will stop.

If I understand correctly, the OP was just using the SSH session to 
check for connectivity, they don't acually want to run a session at that 
point.

If so, the following may work:

while true; do
ssh server : 2>/dev/null && break
done

This will attempt to run the dummy command ":" on "server" (throwing 
away any error messages) until successful. It might be an idea to put a 
"sleep 10" or something in there too.
--
Dom