Bug 1474507 - Need RCA why rabbitmq problems prevented dnsmasq from working.
Summary: Need RCA why rabbitmq problems prevented dnsmasq from working.
Keywords:
Status: CLOSED DUPLICATE of bug 1434593
Alias: None
Product: Red Hat OpenStack
Classification: Red Hat
Component: rabbitmq-server
Version: 10.0 (Newton)
Hardware: Unspecified
OS: Unspecified
urgent
urgent
Target Milestone: ---
: ---
Assignee: Peter Lemenkov
QA Contact: Udi Shkalim
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2017-07-24 19:30 UTC by Jeremy
Modified: 2020-12-14 09:14 UTC (History)
7 users (show)

Fixed In Version:
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed: 2017-09-12 15:01:25 UTC
Target Upstream Version:
Embargoed:


Attachments (Terms of Use)

Description Jeremy 2017-07-24 19:30:47 UTC
Description of problem: The problem the customer noticed is neutron dhcp-agent not starting after package update and after rebooting the controllers. Problem turned out to be with rabbitmq. Question is why was rabbitmq failing and causing other services not to work.


Version-Release number of selected component (if applicable):
rabbitmq-server-3.6.3-6.el7ost.noarch

How reproducible:
unknown

Steps to Reproduce:
1.unknown
2.
3.

Actual results:
rabbitmq db corruption causes dnsmasq not to work.

Expected results:
rabbitmq works properly

Additional info:
Solution was to do pcs resource restart rabbitmq-clone.

Comment 3 Michael Zamot 2017-08-28 19:23:34 UTC
Invalid

Comment 4 Chris Jones 2017-09-11 20:33:00 UTC
@Michael - could you explain your comment "Invalid" please?

Comment 5 Peter Lemenkov 2017-09-12 14:55:06 UTC
I believe we've found what's going on. Short story - please upgrade up to rabbitmq-server-3.6.3-7.el7ost.

Long story. We've tried to speedup various rabbitmqctl operations with experimental out-of-tree patch, which worked rather well in previous RHOS versions. Unfortunately it started causing issues on versions higher that RHOS10 due to changed iptables rules (fairly speaking, improved iptables rules). The same applies to some spiking networking outages, where rabbitmqctl cannot work properly anymore. We reverted back that patch in this version, so everything should work with rabbitmq-server-3.6.3-7.el7ost

Comment 6 Peter Lemenkov 2017-09-12 15:01:25 UTC

*** This bug has been marked as a duplicate of bug 1434593 ***

Comment 7 Michael Zamot 2017-09-12 20:47:52 UTC
The issue reported here is why dnsmasq didn't start when RabbitMQ was down. The explanation is that dnsmasq is started by neutron-dhcp-agent, which won't start if RabbitMQ is down, which is a normal behaviour.

In this case, RabbitMQ was with stuck processes and misbehaving due to networking issues (port flappings).


Note You need to log in before you can comment on or make changes to this bug.