[Libguestfs] v2v: error while killing ssh-agent after importing VM via xen+ssh

[Richard W.M. Jones]

On Wed, Jan 13, 2016 at 09:55:53AM +0200, Shahar Havivi wrote:
> Hi,
> 
> I am successfully importing VM from Xen server at oVirt project via virt-v2v.
> I am setting ssh-agent and running ssh-add before the import process,
> after the import done I am trying to kill the agent via:
> ssh-agent -k (and setting the SSH_AGENT_PID environment), but I get the
> following error:
> kill: No such process
> 
> Can you please explain why there is no agent?

When you run:

   eval `ssh-agent`

ssh-agent starts up and creates several environment variables (which
are added to the environment, because you use the eval `..`).
In particular it sets SSH_AGENT_PID to its own PID.

ssh-agent -k is supposed to read SSH_AGENT_PID from the environment
and kill the previously started ssh-agent process, basically killing
that PID.

It works for me and for lots of other people, so I'm guessing you must
either be running ssh-agent wrongly the first time, or getting the
SSH_AGENT_PID environment variable mixed up somewhere.

> Do I need to delete the agent?

Not necessarily, but if you don't kill the agent then two bad things
can happen: (1) You get lots of ssh-agent processes building up
(2) The ssh-agent processes may be storing your unencrypted private
keys.  Except that ...

> btw I am also running 'ssh-add -d' after the import process with no problems.

... ssh-add -d will remove the private key from the agent.  However
the agent should still be running after this, so it would have no
effect on whether ssh-agent -k would succeed.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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