Azure network throughput

[rob_nicholson_helios]

One of my clients has a performance issue between their remote desktop services server and their file server. When you search on raw network throughput, you get directed to a page about machine sizing and that defines how many NICs you can have and IOPS, which are related but also take the storage into account. 

When one looks at the virtual NICs in each VM, one end is rated 40Gbps and the other 50Gbps. However, when I use LANbench to do some TCP/IP tests, it never goes above 1Gbps which is a suspicious number.

What am I missing here? I can't find anywhere where the speed of the virtual LAN or virtual NICs is defined/configured/shown.

[#2]

PS. I do have the Azure networking cookbook but don't have time to read all 220 pages! So sorry for asking if the answer is in there somewhere.

[#3]

Hi Rob, have you tried and verified one of the following?

- Enable accelerated networking?
- Disk IO is limited by the lowest parameter. Ex: Your VM size has a Max IOPS of 500 and your disk has an IOPS limit of 1000. 500 will be the limit you're hitting.

[#4]

Thanks Yannick - no, don't think accelerated networking is enabled. Will have a look. I assume IOPS applies to both servers?

[#5]

Apologies for not getting back on this, been a bit manic lately... will have a look at those IOPS limits as they sound like the reason. 1Gbps to be honest is fine, just wondered what limit we were hitting as the NIC is 40Mbps