vSphere PowerCLI Quick Start

vSphere Command-Line Interface vCLI or vSphere PowerCLI can be used to manage ESX/ESXi host.  vCLI is supported on  both Windows and Linux Client; PowerCLI is supported Windows Client only,  but it is more powerful than vCLI.

Windows PowerShell basics

 
###Windows Powershell supports wildcard
* ? []
###Window Powershell help
help
help get*
help get-vm
help get-vm -full
###list alias
get-alias
e.g
sort sort-object
ft format-table
fl format-list
###Variable, store result into variable
$var=get-process
#$var becomes array, $var[0] is first process, so it can be used in foreach loop for more complex operations
foreach ($proc in $var) {  $proc.ProcessName}
#The output  can be achieved by format-table
get-process | ft name
###sort, ascending is  default order
get-process| sort cpu -descending
###filter, find notepad process
get-process| where-object { $_.name -eq "notepad" }

vSphere PowerCLI basics

###Install in following order
- install Windows  PowerShell on Window XP/Windows 2003/Windows 2008.
- install vSphere PowerCLI
### First time use
#you will receive certificate warning,  type A to accept it for always run.
#after this you will receive the other  warning about signing,  type this command:
Set-ExecutionPolicy RemoteSigned.
#restart PowerCLI to check if warning disappears.
### Login and execute command
#login
Connect-VIServer -server ServerName
##Some useful commands
#list all vms and sort them by Memory in descending order
#The column real name is MemoryMB, but it is displayed as "Memory (MB)"
# So you need to use fl command to find out the realname ; get-vm vmname | fl
get-vm | sort MemoryMB -descending
#Restart all VMs which are currently Poweredon
#Don't use Restart-VM  because it  is like poweron and poweroff, not #graceful restart
get-vm | where {$_.powerstate -eq "poweredon"} | reset-vmguest
#Read hosts from file
# if you want to exclude some hosts from previous example, you certainly # can add more filter expression but i just want to show how to read file,
#save output to a file
get-vm | where {$_.powerstate -eq "poweredon"}  >d:\temp\host.list
#Edit the file and remove unwanted hosts
#Read the file and restart all hosts in the file, trimend is to remove trailing space
get-content d:\temp\host.list | foreach { $x=$_.trimend() ; reset-vmguest  $x }

Links:

PowerShell quick reference
VBScript-to-Windows PowerShell Conversion Guide
VMware: vSphere PowerCLI Blog

NFS/Samba alternative: Mount remote directory over SSH.

It is possible to mount a remote directory as a local file system through SSH by using SSHFS, which is based on FUSE: a library to create filesystems in userspace. There are many other files system based on FUSE .

Advantage:

Secure and easy to setup, only client side needs install SSHFS and FUSE, the server side just needs SSH server with sftp support.

Disadvantage:

Performance Penalty, because data transferred has to be encrypted and decrypted, which is time consuming and CPU intensive.

Install:

Search and install sshfs using package management tool of your Linux flavour.

Example:

- Mount any remote dir:

sshfs user@server:dir /mnt/sshfs

Only root and users in fuse group can use this command.

- Unmount sshfs

fuserumount -u /mnt/sshfs

or

umount /mnt/sshfs (root user only)