Looking for a bit of guidance / approach to upgrading from Nautilus to Octopus considering CentOS and Ceph-Ansible.
We're presently running a Nautilus cluster (all nodes / daemons 14.2.11 as of this post). - There are 4 monitor-hosts with mon, mgr, and dashboard functions consolidated;
You want an odd number of mons. Add or remove one.
- 4 RGW hosts - 4 ODS costs, with 10 OSDs each. This is planned to scale to 7 nodes with additional OSDs and capacity (considering to do this as part of upgrade process)
Don’t tempt fate. One thing at a time. Not three.
- Currently using ceph-ansible (however it's a process to maintain scripts / configs between playbook versions - although a great framework, not ideal in our case;
^ Kefu ;)
Octopus support on CentOS 7 is limited due to python dependencies, as a result we want to move to CentOS 8 or Ubuntu 20.04.
Do you have a compelling reason to go to Octopus today?
The other outlier is CentOS native Kernel support for LSI2008 (eg. 9211) HBAs which some of our OSD nodes use.
How is this a factor, do newer kernels drop support for that old HBA?
Here's an upgrade path scenario that is being considered. At a high-level:
I suggest that if you are set on doing this, you do one step at a time and don’t try to get fancy. Especially since you only have one cluster. I believe there are Nautlius packages available for CentOS 8 now, so perhaps: * Update each node — serially — to CentOS 8 + new Ceph packages * Update to Octopus via the documented method * Add your new nodes