Johnny Zhang
After ESX 3.5 U2, all version of ESX supports remote Cli. The vifs tools in remote Cli is useful when you need to get log files from a remote host.

C:\Program Files\VMware\VMware VI Remote CLI\bin>vifs.pl -D /host --server bs-bcs-h132.bsl.vmware.com --username root

Now once you know what is there, you might want to get some of those files. let's say i want to get hostd.log from this server, and put the file under my c:/ directory, I can use:

C:\Program Files\VMware\VMware VI Remote CLI\bin>vifs.pl -g /host/hostd.log c:/ --server
bs-bcs-h132.bsl.vmware.com --username root
Johnny Zhang

When connect to an active/active array, esxcfg-mpath will not show you which HBA is currently in use for I/O operation. You can check this out in ESX 4.0 by using

esxcli nmp device list | grep "Working Paths"
You can also find out how many LUNs are connecting through a specific HBA
esxcli nmp device list | grep "Working Paths" | grep -c vmhba#
Note: (Tip was provided by a BCS customer)
Johnny Zhang
VMkernel has it's own error code. When looking at vmkernel log files, some times you need help to understand some of the error codes. You can print them out by using:

vmkerrcode -l | less