Re: vMotion Fails At 14%

Hello Frank,

i read your article and i understand that i imagined the multi-nic vmotion differently.

Although vmotion in ESXi 5 works better than in 4 i think that some improvements should be considered (i'll try to ask them as feature request hoping they could be taken into consideration)

1. multi subnet and multi vlan support (not necessarily meaning we have to set static router in esxi, attached L2 network is just fine)
   
   • this feature could lead to a better use of switches backplane bandwidth (if you use a single addressing and a single vlan the traffic could pass between switch interlink even in non-faulty scenarios)
     
   • some customers (us for example) have different groups of switches not interconnected each other but suitable for vmotion traffic
     
2. ESXi should try to send vmotion traffic on a "path" after having checked that path as available (with keepalives packets exchanged among hosts, multicat or unicast depending on the needs)
   
   • this will prevent failures as we are experiencing now and this could even be useful to chose the best path to use based on keepalive round trip
     
   • keepalive packets round trip could reveal even if a 10G Link is efficient or not, link speed propagated by the network interface card driver is not reliable to determine the real speed a vmotion could achieve
     
3. i imagined milti-nic vmotion a sort of multipath communication with the entire packet to transfer splitted among all the available nics and reassembled on destination, after closing the case i understood that it gives advantages only if more than one vm is vmotioned otherwise only one nic is used
   

Best regards, Roberto Traversi.