openstack team mailing list archive

[Lars Kellogg-Stedman <lars@xxxxxxxxxxxxxxxx>]

On Mon, Jul 30, 2012 at 01:41:20AM +0100, Pádraig Brady wrote:
> Perhaps there is another issue with the scheduling of this?

That's likely. While I verified that the patch successfully fixed our
connection timeout issue, I didn't look closely to see exactly where
the behavior changed...and the connection that is standing out now
belongs to nova-volume, whereas the timouts were happening with
nova-compute.

> How are you monitoring the connection?

Our firewall is a Cisco ASDM (6.1).  I'm monitoring the connection by
running:

  show conn lport 5672

Which gets me:

  TCP compute-hosts:630 10.243.16.151:39756 controllers:621 openstack-controller:5672 idle 0:00:00 Bytes 6410148 FLAGS - UBOI
  TCP compute-hosts:630 10.243.16.151:39881 controllers:621 openstack-controller:5672 idle 0:00:04 Bytes 10470 FLAGS - UBOI
  TCP compute-hosts:630 10.243.16.151:39755 controllers:621 openstack-controller:5672 idle 0:00:02 Bytes 9717108 FLAGS - UBOI
  TCP compute-hosts:630 10.243.16.151:39736 controllers:621 openstack-controller:5672 idle 0:03:59 Bytes 36206 FLAGS - UBOI
  TCP compute-hosts:630 10.243.16.151:39752 controllers:621 openstack-controller:5672 idle 0:00:03 Bytes 4313246 FLAGS - UBOI

Where the fields are:

  <protocol> <source interface> <source ip/port> <dest. interface> <dest ip/port> idle <idle time> ...
 
The connection from port 39736 on the compute host (which is the
nova-volume process) regularly cycles up to 5 minutes of idle time
before resetting to 0 (and the firewall sets the idle time to zero
whenever any traffic passes across the connection).

And indeed, if I run a packet trace on this connection, I can verify
that packets are only showing up at five-minute intervals.

-- 
Lars Kellogg-Stedman <lars@xxxxxxxxxxxxxxxx>       |
Senior Technologist                                | http://ac.seas.harvard.edu/
Academic Computing                                 | http://code.seas.harvard.edu/
Harvard School of Engineering and Applied Sciences |