+++ This bug was initially created as a clone of Bug #1123513 +++
Description of problem:
For node replacement, Installer should provide a way to specify which node in compute cluster should be replaced, it could be down already, or still active.
But new node should attain identity of replaced node, including its network connections and its IP addresses. For this RFE assume that there no user VMs or containers on the node. (for the future we should add RFE for replacing that have user VMs or containers). Start with KVM hypervisor first.
We need a manual process documented prior to incorporating into automated script
For node replacement, for non-HA - not allowed.
For HA is is analogous to taking a node down and adding a new node that assumes it personality. Thus, allows avoiding updating configuration info in other nodes of controller cluster and on Foreman node.
--- Additional comment from arkady kanevsky on 2014-07-26 17:34:19 EDT ---
For node replacement, do not forget to handle populating new node with Ceph keyring if Ceph is used for block backend.
What are the key steps involved in taking a node down and adding a new node that assumes the personality of that node? Is it enough for users to remove that node from the environment and provision a new node all by itself using the same parameters as the previous node?
Fabio, do you have this information? Or have someone who can provide it?
(In reply to Mike Burns from comment #4)
> Fabio, do you have this information? Or have someone who can provide it?
I can´t speak for foreman here, but from a pacemaker cluster perspective, as long as:
- old node is shutdown
- new node has same host name / ip address
It´s enough to re-exchange pcs certificates (pcs cluster auth ...) and pcs cluster setup (on the local node, without --all or copy /etc/corosync.conf from a running node to the new one) and start pacemaker.
Clearly all openstack services have to be pre-configured but i would expect that to happen from puppet deployment.
Andrew, can we get the content from Comment 5 into the docs for A2?
I'll work on some content and see if I can get a draft to you soon.
Just wanted to follow up on comment #7. Did you manage to put together any draft materials on this item?
I'm thinking of putting together an article on this item, partially based on this scaling process in the Installer Guide: https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux_OpenStack_Platform/6/html/Installer_and_Foreman_Guide/chap-Scaling_the_Environment.html
This one was right around the handover time, so I am afraid I do not. My apologies for not adding a comment to the bug at the time to clarify this.
With regards to the article - sounds good. BZ#1172289 also runs along a similar theme. I'll assign that over as well for review.
So this content now exists and is supported in OSP 7:
Spoke with adahms. Agreed that we should focus efforts toward OSP 7 and 8. As a result, closing this BZ.