On 15/05, Souza, Nahim wrote:
Hi, Raghavendra,
Just sharing my experience, I started working on A/A support for NetApp NFS driver, and I followed the same steps you summarized. Besides that, I think the effort is to understand/test if any of the driver features might break in the A/A environment.
If anyone knows about anything else we should test, I would be happy to know too.
Regards, Nahim Souza.
Hi,
I see that there is no mention of deploying and configuring the DLM, which is necessary for the critical sections between different hosts.
For reference, most drivers require code changes. A very common location were drivers need code changes is when creating the host entities in the storage array. I see that the 3PAR driver has already changed that lock to use the DLM locks [1].
If a driver doesn't support replication then there is no need to split the failover_host method.
Cheers, Gorka.
[1]: https://github.com/openstack/cinder/blob/7bca35c935cf8566bcf9e4874be78174cb0...
From: U T, Raghavendra raghavendra-uddhav.tilay@hpe.com Sent: Monday, May 8, 2023 09:18 To: openstack-discuss@lists.openstack.org Subject: [cinder][dev] Add support in driver - Active/Active High Availability
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Hi,
We wish to add Active/Active High Availability to: 1] HPE 3par driver - cinder/cinder/volume/drivers/hpe/hpe_3par_common.py 2] Nimble driver - cinder/cinder/volume/drivers/hpe/nimble.py
Checked documentation at https://docs.openstack.org/cinder/latest/contributor/high_availability.html https://docs.openstack.org/cinder/latest/contributor/high_availability.html#... https://docs.openstack.org/cinder/latest/contributor/high_availability.html#...
Summary of steps: 1] In driver code, set SUPPORTS_ACTIVE_ACTIVE = True 2] Split the method failover_host() into two methods: failover() and failover_completed() 3] In cinder.conf, specify cluster name in [DEFAULT] section cluster = <cluster_name> 4] Configure atleast two nodes in HA and perform testing
Is this sufficient or anything else required ?
Note: For Nimble driver, replication feature is not yet added. So can the above step 2 be skipped?
Appreciate any suggestions / pointers.
Regards, Raghavendra Tilay.