How to use multiple links to storage?

[danswartz]

So I just spun up a server 2019 with an iSCSI link to SAN storage. Server has 2 teamed 1gb links for LAN access and 2 non-teamed 10gb links to the SAN (I've read multiple places you should use MPIO not teaming for iSCSI). The problem is: setting up the iSCSI initiator is documented. Not sure how this works in Hyper-V mode (moving over from vsphere finally). I have 2 links, but for the CIFS share, I can only specify the one address? e.g. '\\192.168.3.44\foo'. Am I missing something? This is certainly not a critical performance issue - mostly curiosity on my part

[danswartz]

This is a bit odd though. I could swear I added the backup proxy and hyper-v hosts as 192.168.3.41 (10gb link), yet the speed is about the maxed expectation for 1gb. And B&R is saying 'bottleneck source'. And looking at the performance monitor networking view on the WS2019 running B&R, I can see much more traffic hitting the 1gb team rather than the 10gb link. Am I missing something?

[danswartz]

Is it maybe because the gateway server (which is itself) is listed via the 10.0.0.7 address (1gb link?)

[danswartz]

I think that was it. The default was the LAN IP for the veeam appliance. I changed it to the storage IP, and reran the 2-vm test job, and speed went from 100MB/s to 450MB/s. I'm going to rerun the full backup of all VMs to test this again.

[danswartz]

No comments?

[PetrM]

Hi Dan,

It seems you've already figured out the reason of performance degradation. Let's wait for the full run result to confirm that the storage IP change was a solution and 3,5x backup speed increase was not just a "happy" coincidence.

I strongly recommend to contact our support team and to share a support case ID with us if the issue persists because our possibility to troubleshoot technical problems over the forum posts is limited.

Thanks!

[danswartz]

I was also hoping for a reply to my 'more than 1 link' question. As I said, this is not an issue, more of a curiosity. And if the answer is: 'you really cannot do more than one link from B&R', I'm fine with that.

[PetrM]

Could you please elaborate a bit more on that question: are you talking about the link between the source Hyper-V host and Veeam B&R or between the repository and Veeam B&R?

Thanks!

[danswartz]

Hyper-V has two 10gb links to SAN. Hyper-V iSCSI initiator is using MPIO to access SAN with round robin - works great. B&R ws2019 VM only has one vnic, so it only sees one of the SAN IP addresses. I never set up the other one, since I can't see how B&R can use 2 IPs to communicate to proxy?

[PetrM]

You can use just a single IP/DNS in order to add the Hyper-V host into Backup Infrastructure. If you want to route backup traffic over a dedicated network to ensure faster data transmission between data movers, then the preferred network might help. You may also take a look at this KB if you need to specify IP ranges other than ranges received by automatic DNS resolution in preferred network settings.

Thanks!

[danswartz]

I'm not being clear, I think. I understand that iSCSI using MPIO can round-robin, improving throughput. AFAIK, there is no way to do this with B&R, correct? e.g. I give it a single IP. Again, this is mostly for my edification.

[PetrM]

Yep, there is no way to do it in Veeam B&R. But just out of curiosity why are you looking for such a setting within Veeam B&R?

The communication between whether on-host or off-host proxy and the storage is transparent for Veeam. Veeam instructs the source Data Mover to read data from the volume snapshot but the Data Mover does not know about underlying physical connection between the host and the storage.

Thanks!

[danswartz]

MPIO for the VM running B&R improves throughput. If it was possible in B&R that might improve throughput as well. But as you say (and not to my surprise), no can do. Thanks!