Table of contents:
Contents
Qpid Support
This page discusses how to use Apache Qpid as the messaging backend for Nova. Using Qpid with Nova would be in place of using RabbitMQ. Qpid support will be first introduced in the Essex release, assuming that this patch goes in.
Dependency Installation
For Nova to use Qpid, you must install a couple of things. You need Qpid's Python client library on any machine running Nova services. You also need at least one instance of the Qpid broker running somewhere.
Fedora
To install the Qpid Python client library:
# yum install python-qpid
To install the Qpid broker:
# yum install qpid-cpp-server
To start the Qpid broker:
# systemctl start qpidd.service
To have the Qpid broker started at boot time:
# chkconfig qpidd on
Ubuntu
Qpid has just recently made it into Ubuntu. It will be in Ubuntu Precise (12.4).
Nova Configuration
All of the options discussed in this section should be set in the /etc/nova/nova.conf file.
Options You Will Use
The current default for Nova (as of Diablo and Essex, at least) is to use the backend that utilizes RabbitMQ as the message broker. You must modify the Nova configuration to tell it to use the Qpid backend. To do this, add the following line to nova.conf:
--rpc_backend=nova.rpc.impl_qpid
By default, the nova services will attempt to connect to the broker on localhost. If you would like to change the Qpid broker host, use the following option:
--qpid_hostname=hostname.example.com
Options You Might Use
If the Qpid broker is listening on a port other than the AMQP default of 5672, you will need to set this option:
--qpid_port=12345
If you configure the Qpid broker to require authentication, you will need to add a username and password to the configuration.
--qpid_username=username
--qpid_password=password
By default, TCP is used as the transport. If you would like to enable SSL, set the following option:
--qpid_protocol=ssl
Options You Probably Won't Use
The following table lists options that are available but are less commonly used than the options discussed above.
Option |
Default |
Description |
--qpid_sasl_mechanisms |
|
A space separated list of acceptable SASL mechanisms to use for authentication. |
--qpid_reconnect |
True |
Whether or not to enable automatic reconnections if a connection is lost. It would be silly to disable this. |
--qpid_reconnect_timeout |
0 |
Timeout for reconnections, in seconds. |
--qpid_reconnect_limit |
0 |
The limit for the number of times to reconnect before considering the connection to be failed. |
--qpid_reconnect_interval_min |
0 |
Minimum number of seconds between connection attempts. |
--qpid_reconnect_interval_max |
0 |
Maximum number of seconds between connection attempts. |
--qpid_reconnect_interval |
0 |
Equivalent to setting --qpid_reconnect_interval_min and --qpid_reconnect_interval_max to the same value. |
--qpid_heartbeat |
5 |
Seconds between heartbeat messages sent to ensure that the connection is still alive. |
--qpid_tcp_nodelay |
True |
Disable Nagle algorithm. |