Bug 1614372

Summary: [RFE] Add option to change the a cluster node's name
Product: Red Hat Enterprise Linux 8 Reporter: Shane Bradley <sbradley>
Component: pcsAssignee: Tomas Jelinek <tojeline>
Status: NEW --- QA Contact: cluster-qe <cluster-qe>
Severity: medium Docs Contact:
Priority: medium    
Version: 8.0CC: ccoursey, cluster-maint, idevat, mlisik, mpospisi, nwahl, omular, sbradley, tojeline
Target Milestone: rcKeywords: FutureFeature, Triaged
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Description Shane Bradley 2018-08-09 14:03:29 UTC
Description of problem:
The ability with pcs to update the node names/address associated with rings in the /etc/corosync/corosync.conf file In addition, update the pacemaker cib.xml file with any changes.

For example, if the end user needed to change their hostname from and update their /etc/hosts entry:
  node42.example2.com

To
  node43.example7.com

Currently this is manual process that requires editing multiple files or commands (like changing pcmk_host_map) which has high probability of introducing typos and errors.

For example a pcs option similar to the following (this assumes the customer has already configured the new hostname and updated /etc/hosts) before running the command:
  # pcs node rename <old name> <new name> ring0_addr=<new name> ring1_addr=<another name>


Version-Release number of selected component (if applicable):
pcs-0.9.162-5.el7_5.1.x86_64

How reproducible:
Does not apply

Steps to Reproduce:
Does not apply

Actual results:
Currently this is manual process that requires editing multiple files which has high probability of introducing typos and errors

Expected results:
The ability to change a cluster nodes name with a pcs command.

Additional info:
A related issue to this is that there is no way to modify, add, remove rings in an existing cluster without manually editing of files. 
  - How do i add or remove support for RRP on a existing pacemaker cluster? 
    https://access.redhat.com/solutions/3354671

There is an existing bugzilla on modifying attributes for corosync already:
  - Bug 1173346 – Allow to modify arbitrary corosync.conf value 
    https://bugzilla.redhat.com/show_bug.cgi?id=1173346

  - Editing the corosync.conf file in Red Hat Enterprise Linux 7 
    https://access.redhat.com/articles/3185291

I realize a change like this would require a restart of the cluster node as I do not see a way around a restart of pacemaker for this type of rfe after node name changed.