Setting up SSH keys - KeegMitch/Operations-Engineering-group-c GitHub Wiki

Generate SSH key

ssh-keygen -t rsa -b 4096 -f ~/.ssh/id_rsa_<server>

e.g.

ssh-keygen -t rsa -b 4096 -f ~/.ssh/id_rsa_db_1

Leave it blank for no passphrase as it will cause problems for when you try and automate your scripts when syncing into the remote servers.

Set the permissions of both the public and private key to this: sudo chmod 600 ~/.ssh/id_rsa_db_1 & sudo chmod 600 ~/.ssh/id_rsa_db_1.pub

Copy into the remote server

Note: This example is from the database server into backup but do this with the storage server as well with mgmt, db, and app

ssh-copy-id -i ~/.ssh/id_rsa_db_1.pub group-c@backup-c

For the storage server to use ssh-copy-id you have to change ownership to this:

sudo chown group-c:group-c ~/.ssh
sudo chown group-c:group-c ~/.ssh/authorized_keys

Manually copy it (not recommended unless you want a constant password prompt)

Copy the contents of your public key into a notepad editor, you can find it using this command

sudo cat ~/.ssh/id_rsa_db_1.pub

Create these if they don't already exist

sudo mkdir -p ~/.ssh
sudo touch ~/.ssh/authorized_keys

Edit the authorized_keys file

sudo vim ~/.ssh/authorized_keys

Paste the contents of your public key here
Restart ssh on both the servers in in question: sudo systemctl restart ssh

Set permissions

sudo chmod 700 ~/.ssh
sudo chmod 600 ~/.ssh/authorized_keys

SSH into the remote server

ssh -i ~/.ssh/id_rsa_db_1 group-c@backup-c

Note: you can also use the -v (verbose) flag to troubleshoot any errors

You should be able to connect to the remote server when you specify the ssh key specific to the server, and it should automatically be added to the authorized_keys file