VMware ESX - Enable flow control on the 10Gb NICs used for SAN

First, update the ESXi 5 host applying all VMware patches. The recommended way to do this is by using VMware Update Manager. Be sure patch ESXi500-201112001 is installed.

1.    At the ESXi console, press [F2] and login as root, select Troubleshooting Options and press [Enter].

2.   Select Enable ESXi Shell and press [Enter].

3.   Press [Alt]+[F1] to open the local console and login as root.

4.   At the ESXi console type:

esxcfg-nics –l

5.   The available NICs are displayed (example: vmnic0, vmnic1, vmnic2…).

Using the output, determine which “vmnic” labels are assigned to adapters used for SAN
connectivity. For example, the two ports on the Broadcom 57711 may be listed as vminc4 and vmnic5.
This will vary depending on the system configuration.

6.   At the ESXi console type:

vi /etc/rc.local

7.   Go to the end of file
Press [Esc], type :$, and then press [Enter] to go to the end of file.
Type the letter “o” (lowercase) to append a new line to the file

8.   Type:

ethtool --pause tx on rx on vmnicX
Substitute the number that corresponds to the NICs identified in step 5 above. Press
[Enter]. Repeat this for each NIC that is connected to the SAN before proceeding to the next step.

9.   Press [Esc], type :wq, and then press [Enter] to save the file.

10. Type:

/sbin/auto-backup.sh