Installation guide

2. Restart the Compute service (which otherwise will encounter errors due to the upgrade of the
Image client package):
# service openstack-nova-compute restart
3. If this results in a new kernel being installed on your systems, you will probably want to
schedule a reboot at some point in the future in order to activate the kernel.
3.4. Met hod - Upgrade Service-by-Service wit h Parallel Comput es
This method is a variation of the service-by-service upgrade, with a change in how the Compute
service is upgraded:
1. Upgrade your system service-by-service, but stop after completing the Dashboard upgrade
(do not upgrade Compute). For details, see Table 3.3, “ Service Upgrade Order and
Instructions” .
2. Run the final yum upg rad e command on systems that are not running Compute services.
See Section 3.3.2, “ Finalize system upgrade” .
3. Set up a parallel Compute environment, installing a new Compute controller and Compute
nodes using the Havana repositories. These systems use a configuration that is basically
identical to that on your Grizzly Compute nodes, making use of the same services that are
also in use by the old un-upgraded Compute deployment (for example, Identity, Image, or
Block Storage). See Section 3.4.1, “Set up a parallel Compute environment” .
Using a parallel environment allows you to slowly migrate workloads to the new Compute
deployment, moving and upgrading physical hosts over to the new release as they become
vacated.
4. Move instances to the Havana Compute nodes. Section 3.4.2, “ Move instances to the new
environment” .
3.4 .1. Set up a parallel Comput e environment
Execute the following steps to set up a new Compute environment, running Red Hat Enterprise Linux
OpenStack Platform 4, that is separate from your old Grizzly environment:
1. Install Compute packages using yum i nstal l packageName.
On the system acting as your Compute API server, install the following packages:
pytho n-no vacl i ent
o penstack-no va-co mmo n
o penstack-no va-co nd ucto r
o penstack-no va-no vncpro xy
o penstack-no va-api
pytho n-no va
o penstack-no va-cert
o penstack-no va-co nso l e
Red Hat Ent erprise Linux O penSt ack Plat form 4 Release Not es
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