Virtual network between VM-s is extremely slow

I have three VM-s running on Windows Azure:

- AD server (small instance)
- MSSQL (medium instance)
- SP2013 (medium instance)

Machines are connected using Virtual Network and this network doesn't have any connections with on-premises environments.

For some reason the farm installation works extremely slow - everything takes long time if it is about network.

I checked the following:

• CPU consumption on all machines is low or near average
• Machines have enough memory
• There doesn't seem to be problems with discs (no high disk queue detected)

Network related issued I detected:

• Data communication between MSSQL and SharePoint is smaller than usual
• Maximum network speed I see between these two is somewhere around 800 kbps
• SharePoint complaints about slow SQL queries

What I can do to optimize my virtual network?

With best regards,
Gunnar Peipman
 
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