Add Proxy to Increase Bandwidth to 1GB SAN

[cffit]

I have a VEEAM Backup server connected to our SAN via iSCSI. Our SAN has 4 1GB physical connections to it. My bottleneck is the 1GB SAN connection between the VEEAM server and the SAN, and even if I team some NICs on the VEEAM server, it still only ever connects at 1GB as I can only connect to one port of the SAN at a time from the VEEAM server.

My question is would adding an additional machine (physcial or virtual) as a proxy, and having that machine point to one of the SAN's open 1GB ports, would I then be able to theoretically double my backup throughput to the SAN? (Assuming that disk I/O wouldn't then become a factor).

[veremin]

Having two proxy servers with each connected to underlying SAN device via separate GB connection should give you better performance rates, indeed. Though, be aware that bottleneck stats just provide you with the information regarding amount of time that every backup component is busy, so the bottleneck is always present (in every setup).

Thanks.

[cffit]

Does anyone do this with NTFS storage? I know that technically you're not supposed to connect to the same NTFS storage with multiple servers. In the case of having two proxies, would I need to then write to two different SAN disk partitions rather than a single one?

[BHB3805]

I have the same issue. I don't believe that there is a way around it - each initiator would have to contact to a separate iSCSI LUN. If your SAN array supports NAS, you could create a CIFS share and the server and proxies can attach to the same share. I do believe that there will be a performance hit(not sure how much). I would interested in what others think.

[cffit]

I guess looking back and knowing then what I know now, I would have created a couple LUNS on the SAN rather than one large one, then connected the VEEAM server (with proxy role) to one and then connect the other LUN to a different server with the proxy role. Then I would have issues backing up to tape though going over the 1GB iSCSI newtork.

Obviously 10GB iSCSI would have been a nice solution to this all had it been more affordable.

[dellock6]

Christensen, even with ethernet teaming (etherchannel or whatever the network vendor calls it) you need to be aware etherchannel only uses one pipe per connection. So, since your proxy has 1 IP and so does your storage, it will always use 1 GB link regardless the number of nis you aggregate on the etherchannel.
Adding a second proxy is not a sure solution, since there is no guarantee the two servers will use one pipe each. Etherchannel has no way to send one server to each pipe, and you could also end up having at sime time both servers using the same link.

Having no informations on your storage, I can only give you general advice: if the iscsi storage can have multiple IPs on its connections, remove etherchannel and set at least two different IPs on the storage. Than configure the proxies using the Windows MPIO (multipath IO) so they can reach both IP of the SAN. At this point the two proxies would use policies like roun robin and thus be able to go over both links.

Luca.