I’m using serveral ESX 3.5 U5 connected to 2 HP ProCurve 3500yl.
When I monitor my Equallogic SAN with SAN Headquarters 2.0 there are a lot of TCP Retransmits. Sometimes more than 3%. After some troubleshooting I discovered the TCP Retransmits are caused by the ESX Nic Teaming connected to the HP ProCurve switches.
Every ESX server has 2 NICs connected to the iSCSI for VMFS and iSCSI Initiators from the VM’s. Both NICs are connected to a different switch for redundancy. So for example ESX NIC 1 is connected to port 1 from switch X and ESX NIC 2 is connected to port 1 from switch Y. Port 1 from both switches are configured as a trunk ( Trunk1 ) not using LACP. Between the 2 switches there is a different trunk configured for the data that needs to be directed to another switch.
I configured my ESX Nic Teaming like this.
Port 1 trough 4 on both HP ProCurve switches are used to link the 2 switches together. Here is the relevant config lines from the switch.interface 1 name “Switch Trunk” flow-control no power-over-ethernet exit interface 2 name “Switch Trunk” flow-control no power-over-ethernet exit interface 3 name “Switch Trunk” flow-control no power-over-ethernet exit interface 4 name “Switch Trunk” flow-control no power-over-ethernet exit trunk 1-4 Trk1 Trunk vlan 1
no untagged 5-36,38,40,42,44,46,48,Trk1-Trk7
no ip address
jumbo ip-mtu 8982
jumbo max-frame-size 9000
spanning-tree Trk1 priority 4
Here is the config for the port used by the ESX server.interface 47 name “VM-OZ-01” flow-control no power-over-ethernet exit trunk 47 Trk2 Trunk spanning-tree Trk2 priority 4
Anyone some bright ideas how to resolve this problem?
When browsing the internet for config problems between HP ProCurve switches and ESX 3.5 I found the following websites. After reading this I came to the conclusion my config is the same as recommended here.
As it turns out HP does not support teaming over 2 switches ( yet ).
This means the ports in Trunk 1 of switch x does not share the MAC adresses with the ports in Trunk 1 of switch y.
So there are 2 solutions left.
- Connect both NICs from the ESX server on 1 HP switch.In VMWare configure the VSwitch with both NICs as active. Setup a trunk on this switch with 2 ports.
Load balancing works, but no redundancy.
- Connect 1 NIC to switch x and 1 NIC to switch y. In VMWare configure the VSwitch with 1 NIC as active and 1 NIC as standby. Setup a trunk in not necessary.
No Load balancing, but you will have redundancy.
I settled for now with solution 2.
Monitoring the NICs from my ESX servers with Cacti to monitor the load from the NICs.
Still searching for a solution with both load balancing as redundancy.