I am working with a customer who is having a Hyper-V cluster, after getting the Network Adapters sorted out I noticed the RDP connectivity to the server was poor. A ping to the default gateway revealed high ping latency and a good handful of request time-outs.
- Updated the drivers - No change.
- Changed the CAT6 cable - No change.
- Disabled VMQ - No change.
- Plugged my laptop in to the same cable - Same issue, Bingo! This turned out to be a red herring. I updated my drivers and plugged the power in and that resolved the laptop ping issue.
- Tried another laptop on the same cable - It was fine, 1ms.
- Tried another 1GbE NIC to eliminate the LBFO driver - still the same.
- Tried a 10GbE - Seems to be stable, odd.
- Tried another switch - Seems to be stable, odd.
- Flatted the server, installed Windows 2012 R2 again and test the ping, it was fine, odd!
- Repeated all the configuration steps one at a time each time testing the ping, still OK.
- Joined the domain, BAM! Pings all over the shop.
- Tried safe mode, Seems to be stable 1ms!
- Removed the server from the domain, seems to be stable 1ms.
- Added the server back to the domain, pings latent and intermittent again.
- Stop the Base Filter Engine (stop-service BFE - force), seems to be stable 1ms.
- Uninstall the Broadcom driver and use the OOB driver from Microsoft, seems to be stable 1ms.
Update: After creating some VMs the problem moved inside some VMs. The solution was to change the Broadcom 1GbE NICs for Intel x350-t NICs.
Hardware, Dell PowerEdge R720, 1GbE & 10GbE Broadcom NICs. Switch HP 5400