Johnny Zhang
Do you know you can run one command to get some important information about your host?

vmware-vim-cmd "/hostsvc/hostsummary" | less

What you are looking for is hardware info:
(Server type, CPU and Memory info)

and software info: (Host name, Management port, ESX version and build, If the host require reboot, and management server IP if you set one)

Johnny Zhang
In ESX 4.0 the fail over component is also a plug-in called PSP (Path Selection Plugin).
to list them you can run:

esxcli nmp psp list
Most Recently Used (MRU) — Selects the first working path discovered at system boot time. If this path becomes unavailable, the ESX host switches to an alternative path and continues to use the new path while it is available.

Fixed — Uses the designated preferred path, if it has been configured. Otherwise, it uses the first working path discovered at system boot time. If the ESX host cannot use the preferred path, it selects a random alternative available path. The ESX host automatically reverts back to the preferred path as soon as the path becomes available.

Round Robin (RR) – Uses an automatic path selection rotating through all available paths and enabling load balancing across the paths.

Note: Information based on Cormac Hogan 's storage training slides
Johnny Zhang
In ESX 4.0 the array type components is a plug-in, it called SATP (Storage Array Type Plugin) You can use the default one shipped with ESX server (Works for most arrays) or use the one from SAN vendor if they have one available. To check what plug-ins are installed on the host.

esxcli nmp satp list
You can really dig into destails by using "esxcli nmp satp listrules"
Johnny Zhang
ESX 4.0 uses the unique LUN identifiers, typically the NAA (Network Addressing Authority) id. We can find out from the ESX host side if the LUN is unique.

esxcli nmp device list
The device starts with "naa" uses Network Addressing Authority, and it's unique. The one starts with "mpx" does not have a unique ID. In our case this is a local disk. It would be a good idea to make sure we have unique disks when the SAN team persent them to ESX servers.
Johnny Zhang
I think we are all used to the SSL certificate warning when using your VIClient to connect to your vCenter or ESX server. It would be nice we can bypass it. In fact, you can. You can do this for both VI3 and vSphere 4

You can right click on your viclient --> Properties --> find the Target: on my system is "C:\Program Files\VMware\Infrastructure\Virtual Infrastructure Client\Launcher\VpxClient.exe"

add a switch "-i yes" to the end make it like:
"C:\Program Files\VMware\Infrastructure\Virtual Infrastructure Client\Launcher\VpxClient.exe" -i yes

Click ok
That's it, no more SSL certificate warning.

Note: The test on vSphere client did not work, seems like it will loop back to check the SSL certificate even after by pass it from the beginning. Not sure this is a minor bug.
Johnny Zhang
The service console's /proc directory gives us some good information. How do I know my DRS setting for the VMs on this hosts?

less -RS /proc/vmware/sched/drm-stats

gid 0 is the resource group for the host. Check balloon and swap to monitor the host resource usage.
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