I hate PowerCLI. There. I said it. I’m not a programmer. I can barely script. My upcoming VCAP exam pretty much requires some proficiency in PowerCLI. Perhaps you see my dilemma. Since I have to know it, I figured I’d better learn it. I decided to get started with something relatively simpe: Backing up my host configs. I’m going to show you how and I’m going to explain the commands.
Fortunately, this particular function is pretty easy. It’s just a single line:
Get-VMHost | Get-VMHostFirmware -BackupConfiguration -DestinationPath <some path>
Get-VMHost lists all of the hosts connected to your endpoint. In other words, if you’re connected to your vCenter server, it will list all hosts in all clusters on that server. If you’re connected to a single host, it will list that host.
Get-VMHostFirmware lists the URL path of the configBundle.tgz that we’ll retrieve.
-BackupConfiguration tells Get-VMHostFirmware to download the .tgz
-DestinationPath tells it where to put it.
We take the results of Get-VMHost and run them (using the pipe symbol: | ) through the Get-VMHostFirmware command, using the switches as defined. If Get-VMHost returns multiple hosts, it will iterate through each of them automatically.
You’ll see something like this:
The restore command is just as easy. Just use “Set” and “Restore”:
Get-VMHost <hostname> | Set-VMHostFirmware -Restore -DestinationPath <full path to .tgz file>
Your host should be in maintenance mode and it will auto-reboot, so be careful here.
Just for completeness’ sake, here’s the VCLI way to do it. It’s just another single command, run from VMware CLI:
vicfg-cfgbackup.pl –server <server name or IP> -s “<full path to .tgz file>”
And here’s what it looks like:
You’ll notice that when you use vicfg-cfgbackup.pl that you have to specify a filename as well. When you have several (or many) hosts to backup, it’s better to use PowerCLI because you can get all of them in one go.
By the way, the restore command is:
vicfg-cfgbackup.pl –server <server name or IP> -l “<full path to .tgz file>”
Here, we just changed the “S” to an “L”. Remember that the host will still go into maintenance mode and reboot, so make sure you’re prepared. Also, when restoring configs, you’ll want to try to make sure that your host is at the same version and build level as it was when you took the backup.
These are fairly simple, routine administrative tasks but if you don’t know how to do them, you don’t know how to do them. I hope you found this useful.