Steps
- Create folder
mkdir /home/user/.ssh/folder
if not already exists ssh-keygen
-> Enter folder and file name of key- Change ownership of folder
sudo chown -R user:user /home/user/.ssh/folder/keyname
- Add key to ssh
ssh-add /home/user/.ssh/folder/keyname
- Update config
nano ~/.ssh/config
Host github.com
User git
IdentityFile /path/to/your/custom_key
- Copy key.pub to https://github.com/settings/keys
Tip:
Above steps applicable for any service or server and if that server needs to get the pub key for SSH access into it,
ssh-copy-id -i ~/.ssh/keyname.pub user@ipaddr