yahoo-eng-team team mailing list archive

[Rossella Sblendido <rsblendido@xxxxxxxx>]

Public bug reported:

I didn't experience it myself, I got an email from Tom Carroll
explaining this problem with lots of details. I thought I'd file a bug
so that other people can benefit.

This is the report:

"I've been attempting to use liberty neutron on XenServer and I've
noticed some changes that make it difficult to do so.  These changes
begin with commit 3543d8858691c1a709127e25fc0838e054bd34ef, the
delegating of is_active() to AsyncProcess.

The root cause of the problem is that the root helper, in this, neutron-
rootwrap-xen-dom0, runs in a domU, but executes commands in dom0.

In this scenario, AsyncProcess.pid returns None. This is due to trying
to travel from the root helper down to leaf children. And again, the
children are running in a different dom. As a consequence,
AsyncProcess.is_active() returns false, causing the ovsdb client to be
eventually respawned.

Another complicating scenario, is neutron-rootwrap-xen-dom0 communicates
with dom0 using an XMLRPC style protocol. It reads the entire stdin,
launches the command in dom0 providing the buffer to stdin, reads the
entire stdout, and responds back. If the command never ends, a response
will never be returned.

The end result is that new interfaces are never annotated with the
proper 1Q tag, which means that the network is inoperable for the VM.

A complete restart of the neutron agent, fixesup the networking."

** Affects: neutron
     Importance: Undecided
     Assignee: Tom Carroll (h-thomas-carroll)
         Status: New

** Changed in: neutron
     Assignee: (unassigned) => Tom Carroll (h-thomas-carroll)

-- 
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to neutron.
https://bugs.launchpad.net/bugs/1533704

Title:
  networking doesn't work for VMs on xen

Status in neutron:
  New

Bug description:
  I didn't experience it myself, I got an email from Tom Carroll
  explaining this problem with lots of details. I thought I'd file a bug
  so that other people can benefit.

  This is the report:

  "I've been attempting to use liberty neutron on XenServer and I've
  noticed some changes that make it difficult to do so.  These changes
  begin with commit 3543d8858691c1a709127e25fc0838e054bd34ef, the
  delegating of is_active() to AsyncProcess.

  The root cause of the problem is that the root helper, in this,
  neutron-rootwrap-xen-dom0, runs in a domU, but executes commands in
  dom0.

  In this scenario, AsyncProcess.pid returns None. This is due to trying
  to travel from the root helper down to leaf children. And again, the
  children are running in a different dom. As a consequence,
  AsyncProcess.is_active() returns false, causing the ovsdb client to be
  eventually respawned.

  Another complicating scenario, is neutron-rootwrap-xen-dom0
  communicates with dom0 using an XMLRPC style protocol. It reads the
  entire stdin, launches the command in dom0 providing the buffer to
  stdin, reads the entire stdout, and responds back. If the command
  never ends, a response will never be returned.

  The end result is that new interfaces are never annotated with the
  proper 1Q tag, which means that the network is inoperable for the VM.

  A complete restart of the neutron agent, fixesup the networking."

To manage notifications about this bug go to:
https://bugs.launchpad.net/neutron/+bug/1533704/+subscriptions