Trim table of text and store values as variables - linux

Question

I am trying to write a script that can be run on my FreeNas (FreeBSD) box, that connects to an ESXi host via SSH and gracefully shuts down VMs. What I need to run for a list of VM IDs is:
vim-cmd vmsvc/power.shutdown VMID
Am after some assistance in filtering the output of the commands used to retrieve the IDs, and then passing it to the shutdown command.
The command to retrieve all VMs is:
vim-cmd vmsvc/getallvms
It outputs data like this:
Vmid Name File Guest OS Version Annotation
12 Eds-LINUX [Eds-FS-Datastore-1] Eds-LINUX/Eds-LINUX.vmx ubuntu64Guest vmx-13
13 Eds-RT [Eds-FS-Datastore-1] Eds-RT/Eds-RT.vmx freebsd64Guest vmx-13
14 Eds-DC [Eds-FS-Datastore-1] Eds-DC/Eds-DC.vmx windows9Server64Guest vmx-13
15 Eds-STEAM [Eds-FS-Datastore-1] Eds-STEAM/Eds-STEAM.vmx windows9_64Guest vmx-13
16 Eds-DL [Eds-FS-Datastore-1] Eds-DL/Eds-DL.vmx windows9Server64Guest vmx-13
17 Eds-RD [Eds-FS-Datastore-1] Eds-RD/Eds-RD.vmx windows9Server64Guest vmx-13
18 Eds-PLEX [Eds-FS-Datastore-1] Eds-PLEX/Eds-PLEX.vmx windows9Server64Guest vmx-13
19 Eds-MC [Eds-FS-Datastore-1] Eds-MC/Eds-MC.vmx windows9Server64Guest vmx-13
2 Eds-FS [Eds-ESXi-Datastore-1] Eds-FS/Eds-FS.vmx freebsd64Guest vmx-13
I have determined I can use a pipe into sed, to delete the first line, using:
vim-cmd vmsvc/getallvms | sed '1d'
I am then able to retrieve the ID of the VM I want to filter out, by using:
vim-cmd vmsvc/getallvms | awk '/Eds-FS.vmx/{print$1}'
This gives me the ID of 2. I am unclear however, how to store this in a variable for later use.
I need to know of a way to select just the first column from this data, and for each ID in the list, put it in an array. I then need to loop through the array and for each ID, run the below to get the power state of the VM:
vim-cmd vmsvc/power.getstate VMID
This outputs data like this, with a status of either power on or off:
Retrieved runtime info
Powered on
For each one that is found to be powered on, I need to store the VM ID in a second array to later pass to the shutdown command, except for where the ID is equal to that of the VM I want to power off.

Answer 1

Thanks to anubhava who gave me enough assistance to get something working (although probably not following standards or best practices)
I have this script saved on my ESXi host, which I connect to with SSH and trigger a run of:
freenasid=`vim-cmd vmsvc/getallvms | sed '1d' | awk '/Eds-FS.vmx/{print$1}'`
vmids=`vim-cmd vmsvc/getallvms | sed '1d' | awk '{print$1}'`
for vmid in $vmids
do
if [ $vmid != $freenasid ]
then
powerstate=`vim-cmd vmsvc/power.getstate $vmid | sed '1d'`
if [ "$powerstate" = "Powered on" ]
then
onvmids="$onvmids $vmid"
fi
fi
done
for vmid in $onvmids
do
vim-cmd vmsvc/power.shutdown $vmid
done
exit 0
This correctly shutsdown all running VMs.

Answer 2

To list IDs from first column use awk like this:
vim-cmd vmsvc/getallvms | awk 'NR>1{print $1}'
To store IDs in a shell array use:
readarray -t arr < <(vim-cmd vmsvc/getallvms | awk 'NR>1{print $1}')
To loop through array and run another command:
for id in "${arr[#]}"; do
vim-cmd vmsvc/power.getstate "$id"
done
To store one particular id use command substitution:
vmid1=$(vim-cmd vmsvc/getallvms | awk '/Eds-FS\.vmx/{print$1}')