Document of how to use FLow Controll in Nutanix enviroment

  • 21 April 2014
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After some tests , I must say , there is much work to figure out the right configuration for the 10 Gigabit network.
Found following:
With ESXi 5.0 U3 :
ethtool –show-pause vmnic0
autonegotiate : on
rx : on
tx :on
With ESXi 5.5:
autonegotiate : on
rx : off
tx :off
First thought it is ESXI specific, but it depends on the installed driver for ixgbe.
There different hints for folling websites:
http://www.seanxwang.com/2011/03/cisco-flow-control-with-netapp-nas.html
Now let’s revisit the flow control scenario again, NAS sends Pause, switches receives it, there is no use applying back pressure all the way to the host since host won’t receive it. The best a switch can do is to buffer it, or apply back pressure to upstream, and have the upstream switch buffer somewhere. How well that works really depends on the switch and linecard models, each have different capabilities and buffer size. In many cases, it is highly questionable how far back flow control is propagating to have any positive effect. In any case, you want to check:
  • Switch interface to NAS, to see the amount of Pause received
  • All interfaces where NAS traffic flows, to see if there are drops
http://rickardnobel.se/esxi-and-flow-control/
Should autonegotion be on for a intel 82599eb nic in supermicro server, which only can do Full Duplex?
kb.vmware.com/kb/1004089

Modifying the rc.local or local.sh file in ESX/ESXi to execute commands while booting
http://kb.vmware.com/selfservice/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=2043564
Add this line in local.sh:
ethtool --pause vmnic0 autoneg off

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