ESX iSCSI and Replication.

[budy]

Hi Todd,

this is hitting my as well. So there's a good chance that the data on the replicated volume will take damage, if wb is enabled on the source LV?

Thanks,
budy

[To-M]

Yes but not in all instances as some applications are aware of the data not being transferred and will resend what is missing but this will be a very small amount and in most cases to small. We will be looking into some feature to replicate the cache in the future. But this is a very $$$ feature even with our competitors it is extremly expensive.

[budy]

I see.

Just for completeness, does this then apply to normal, replicated iSCSI volumes as well, or is this ESX-specific.

E.g. if I have an iSCSI volume mounted on a CentOS box and thas volume has replication enabled, do I need to worry about this at all then?

Thanks,
budy

[To-M]

We did not test all scenarios only with the ESX environment when using the Auto Failover and enabling the Write Back option. When we disabled the Write Back option we did not see this issue. Though with this Write Back option disabled there is a small performance hit.