On 9 Nov 2016, at 09:57, Francesco Romani <fromani@redhat.com> wrote:
----- Original Message -----
From: "Piotr Kliczewski" <pkliczew@redhat.com> To: "Martin Sivak" <msivak@redhat.com> Cc: "Michal Skrivanek" <michal.skrivanek@redhat.com>, "Francesco Romani" <fromani@redhat.com>, "Shira Maximov" <mshira@redhat.com>, "devel" <devel@ovirt.org> Sent: Wednesday, November 9, 2016 9:54:02 AM Subject: Re: [ovirt-devel] [vdsm] Connection refused when talking to jsonrpc
On Wed, Nov 9, 2016 at 9:48 AM, Martin Sivak <msivak@redhat.com> wrote:
Isn’t the most likely cause by far a simple startup delay? We do open the listener “soon” and responds with code 99, but it’s still not instant of course
That is possible of course and we handle those "errors" just fine. But connection refused never happened with xmlrpc. It might have been luck, but it always worked there :)
There is no difference how we open listening socket (it is used by both protocols) and I have seen the engine attempting to connect using both protocols before the socket was open. What is the time difference that you see?
Not sure I reproduced correctly, but it seems a race on startup. I got the same error on my box, and here it happens if mom tries to connect to the unix socket /var/run/vdsm/mom-vdsm.sock *before* that Vdsm creates it. Once vdsmd succesfully starts, a restart of mom-vdsm seems to fix all the issues.
I'm not sure yet if that's all of it and how to handle with systemd dependencies. Perhaps Nir's suggestion past in the thread to notify systemd is a good first step in the right direction.
not sure we would need to wait for recovery to finish if you want to be really nice to “dumb” clients that would take too long though I think mom needs a fix in addition anyway
HTH,
-- Francesco Romani Red Hat Engineering Virtualization R & D Phone: 8261328 IRC: fromani