Hyper-V Slow network connection for only one of 5 machines on

notcjw used Ask the Experts™
I am running Hyper-V with 6 virtual machines.  One virtual machine is running MSSQL Server 2012.  The network speed for 4 of the servers connecting to the sql server are the same but the 5th server's connecting to the SQL server takes about twice as long.

When I open the Hyper-V manager and look at the network adapter settings for the slow connecting machine, the settings are identical to the other machines.
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Technical Architect - HA/Compute/Storage
What is the hardware setup?

I have two very thorough EE articles on all things Hyper-V:

Some Hyper-V Hardware and Software Best Practices
Practical Hyper-V Performance Expectations

If there are Broadcom Gigabit NIC ports in the server then the first article explains what Virtual Machine Queues (VMQs) are and why when enabled on Gigabit ports packets sometimes do weird things like stall. VMQ needs to be disabled on all Broadcom Gigabit ports at the driver level.


Disabling VMQ solved the problem .Thanks!!!!

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