Unable to mount an external persistent disk as part of startup script in Google compute engine

Question

I am trying to mount my external persistent disk using the command:

sudo mount -o discard, defaults /dev/sdb /mnt/working

what I want to do is to make it part of the startup script as I start my VM. I followed the instructions as per the link: https://cloud.google.com/compute/docs/startupscript#startupscriptrunninginstances

I added the script as follows:

custom metadata
key                       value
startup-script            #! /bin/bash
                           sudo mount -o discard,defaults /dev/sdb /mnt/working

However when I restart my VM , it does not execute it. What am I doing wrong here ?

EDITED to provide more information

Image: debian-10-buster-v20200910 I have not enabled error logging as I am not using the free version anymore but I am hoping that the default log viewer will show error logs. I don't see any. I also ran the script by logging into the vm instance:

sudo google_metadata_script_runner startup  

This also didn't help.

Answer 1

Issue was primarily a newline character between /mnt/sdb /mnt/working. This prevented from the startup script from getting executed. Thanks to the tip from Lukaszberwid, I ran the

 sudo journalctl -u google-startup-scripts.service

was able to spot the issue. I was wondering if the metadata value field for the startup script can be expanded to the right or made little bigger to spot such cut and paste issues.