Extremely slow RX/TX when using VLANs in a bonded VM Network
Jeff_JOct 1 2012 — edited Oct 1 2012We recently installed an HP NC 695T - quad port Intel NIC (82580) in an OVM server, in order to create a bond and give our VM network which is VLANed some switch redundancy.
Everything went to plan, however when we fired up the VMs, we noticed the morning after the nightly backup was still running - which usually completes in quarter of an hour. CPU / RAM on the VM was fine, so we did some basic network tests with Netio - and discovered that the bandwidth of stuff passing out of the vnic bridge was something like 0.3MB/s. Crazy. We had created an active/passive bond. We changed it to ALB just to see if that might affect anything, but no. We then shut down one of the ports on the switch again for tests, but again nothing. Finally we shut down the VM, removed the server from the VLAN group, deleted the bond, re-added the server to the VLAN group this time with a single non-bonded NIC - and hey presto - back to normal.
The same server has ALB bonding on Management and Storage networks - not VLAN'd and these appear to work fine.
We only tested with Windows VM guests, so it's possible this could be a Windows PV driver issue.
It could also be a NIC issue....
Anyone else seen this?
Jeff