DEV Community

ssh - a treat for your GitHub

Abhishek S. Sharma on August 08, 2020

ssh commands ssh creation ssh key should be in /home/.ssh folder to generate ssh key- ssh-keygen the command will ask you the ...

Read full post

Thomas H Jones II • Aug 8 '20

An easier method for copying your public key to a remote host is to use the ssh-copy-id command.

Also, if you have multiple SSH keys on your keyring, you can create scenarios where the git-remote will give you a "too many authentication failures" error due to the ssh-agent presenting the wrong key(s) prior to the correct key.

Daniel Lintott • Aug 9 '20

Using the SSH config file (~/.ssh/config) can come in handy here.

Specify the remote server you are connecting to using the Hoststatement.

Within the host statement you can specify the options that differ from the defaults for that host including but not limited to username and identity.

Host example.com
    User fred
    Identity File ~/.ssh/example-key

Then when you connect to the example.com server it will use the options you have specified. On some OSes this also provides auto-completion for the SSH command.

The SSH Config Man page has all the options you can specify linux.die.net/man/5/ssh_config

Krzysztof • Aug 9 '20

I do second ssh-copy-id. Got to know about it few weeks ago and it's such a helper!

Kevin Woblick • Aug 9 '20

You should consider using modern ECDSA SSH keys instead of the old RSA keys. They are more secure and supported on all modern systems.
Details about ECDSA and how to generate them can be found in my article.

Donald Brown • Aug 9 '20

If you don't want to read a whole article to figure out how to generate this type of key, simply add -t ecdsa to the ssh-keygen command. The why in the article, though, is still a good read.

/dev/sam1 • Aug 9 '20

Ackchually, Ed25519 is now the go-to recommended algorithm

Donald Brown • Aug 9 '20

You should not use sudo when modifying authorised keys. If the file does not already exist, it will set the wrong permissions. Authorised keys is a strictly user file and should only ever be accessed by the user that owns it. Overuse of sudo is a dangerous trend that should not be encouraged.

Kartik Saxena • Aug 8 '20

Nice work..

urkary • Aug 10 '20

I do not use ssh-agent and when using 2 GitHub accounts I use the GIT_SSH_COMMAND variable to specify the key to use. Not sure of this is right or the best way to do it, but it has been useful to me so far