How to/Design - 2x Truenas Scale hosts - iscsi targets 3x VMware Hosts - Real-time replication of the iscsi vdevs/failover?

[Murphy1138]

Hi All, looking for a solution or how to guide.

My current setup is a single Truenas Scale host on a Dell 740Xd2 with 24xspinners in 20 Mirrored vdevs and 4x hotspares and 2x P3700 ZIL cache NVME disks.

This presents 3x iscsi zvols to 3x VMware hosts controlled by vSphere via multipath 10GB networking, I run 60VMs.

This works well, and I keep the pool at or around 50% full and each zvol around 50%.

What I want to try and do is spin up another identical server, replicate the zvols and have vmware setup to failover to the "passive" server in the event the main server has a wobble or crashes.
Is it possible? If so how? Any guides? I have been searching high and low and can't find anything.

Currently, if the TrueNAS needs maintenance or updates, I use storage vMotion off to a Qnap SAN, do the updates and vMotion back. It does not solve my single point of failure.

If this is not possible in anyway, could someone let me know so I can stop thinking about it, many thanks!

Thanks,
Tom

 

[morganL]

Hi All, looking for a solution or how to guide.

My current setup is a single Truenas Scale host on a Dell 740Xd2 with 24xspinners in 20 Mirrored vdevs and 4x hotspares and 2x P3700 ZIL cache NVME disks.

This presents 3x iscsi zvols to 3x VMware hosts controlled by vSphere via multipath 10GB networking, I run 60VMs.

This works well, and I keep the pool at or around 50% full and each zvol around 50%.

What I want to try and do is spin up another identical server, replicate the zvols and have vmware setup to failover to the "passive" server in the event the main server has a wobble or crashes.
Is it possible? If so how? Any guides? I have been searching high and low and can't find anything.

Currently, if the TrueNAS needs maintenance or updates, I use storage vMotion off to a Qnap SAN, do the updates and vMotion back. It does not solve my single point of failure.

If this is not possible in anyway, could someone let me know so I can stop thinking about it, many thanks!

Thanks,
Tom

TrueNAS Enterprise appliances use dual controllers to perform this capability. Its possible because they use shared storage (single ZFS pool). No data is lost on failover.

On standard servers, you can snapshot and replicate (every 5 minutes) to a secondary NAS. OK if you don't mind losing 5 minutes of data.

 

[Murphy1138]

Thanks for the reply, I'm guessing you can't have VMware talking via Iscsi to the replicated server as it would be a different LUN path and ID. So I would have to reconfigure VMware to talk to the replicated LUNs in the event of a fail of the main server.

 

[morganL]

Thanks for the reply, I'm guessing you can't have VMware talking via Iscsi to the replicated server as it would be a different LUN path and ID. So I would have to reconfigure VMware to talk to the replicated LUNs in the event of a fail of the main server.

Yes, it would be a manual process...

 

[Murphy1138]

Yes, it would be a manual process...

Thanks, Im in touch with IX about buying a proper setup. Thanks again!