ssh – Uly.me

July 20, 2021

GCP SSH Issues

There are a few issues that prop up every once in a while with gcloud compute ssh. gcloud compute ssh creates local user at first login. The account password has a default expiration of 90 days. If unable to login, you can try logging in as a different name (even a fictitious name) e.g. superheroes, etc. something unique.

gcloud compute ssh username@servername --zone us-central1-c --project project-id --internal-ip

Once logged in, you can delete local users with expired passwords or perform other admin tasks.

userdel -r username

You can also try to run chage to adjust the password expiration.

chage -M 180 username  (extends expiration from 90 to 180 days)

If you continue to have login issues, you can also delete Metadata SSH keys in both the instance and project levels.

Last resort you can use force key overwrite which will regenerate a new key and overwrite broken ssh keys.

gcloud compute ssh username@servername \
--force-key-file-overwrite \
--zone us-central1-c \
--project project-id \
--internal-ip

July 16, 2021

GCP SSH Issues Return Code [1]

If you are getting this return code [1] error, check if enable-oslogin metadata is set to TRUE in your VM.

Here’s the error when logging in.

gcloud compute ssh your-server-name \
--zone us-central1-a \
--project your-project-id \
--internal-ip &
ERROR: (gcloud.compute.ssh) [C:\Program Files (x86)\Google\Cloud SDK\google-cloud-sdk\bin\sdk\plink.exe] exited with return code [1].

Remove metadata.

gcloud compute instances remove-metadata your-server-name \
--keys=enable-oslogin \
--zone us-central1-a \
--project your-project-id
Updated [https://www.googleapis.com/compute/v1/projects/your-project-id/zones/us-central1-a/instances/your-server-name].

Run gcloud ssh again.

gcloud compute ssh your-server-name \
--zone us-central1-a \
--project your-project-id \
--internal-ip &
[1] 1257

This time it opens up a Putty session and you’re able to login.

October 15, 2020

SSH Script

Here’s my custom ssh script named login.sh using multiple arguments.

#!/bin/bash
if [ $# -eq 0 ]
  then
    echo 'no server supplied'
        exit 1
fi
INPUT=$2
case "$INPUT" in
  abc)
    ssh user1@$1
    ;;
  def)
    ssh user2@$1
    ;;
  *)
    ssh user3@$1
    ;;
esac

How to use with expected outputs.

./login.sh
no server supplied
./login.sh server3 abc
ssh user1@server3
./login.sh server2 def
ssh user2@server2
./login.sh server1
ssh user3@server1