SSH with a user alias?

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Is it possible to assign nicknames or aliases to users on a Linux sever and SSH into the server using the nicknames? I am thinking something along the lines of the aliases for various commands that get added to the .bashrc or the .bash_aliases file, e.g.:

alias grep='grep --color=auto'

For example, if there is a requirement (business rule) to set up users on the server with their full name, e.g., john_smith instead of just their first name (john) but we want to nickname john_smith fruitloops and we want John to be able to:

ssh john_smith@ip_address

as well as:

ssh fruitloops@ip_address

If it is possible, where would the mapping between a user and their nickname be set up? Would the user fruitloops also need to exists on the sever?

This question is about setting up an alias for a user, not a host.

2 Answers

Each user in linux has only one name and that is his only name. you can create aliases for commands not for users.

But you can create a second user with the same UID, home directory and password that would do the trick for you.

I haven't tried this but another option besides the two users mapped to a single UID (which IMO seems dangerous but this option is probably equally dangerous) is to have a single user serve as a redirector based on SSH key. This is how source control repositories that use SSH typically work.

Lets call the user me. Everyone will use this alias.

ssh me@ip_address

Now the user me has all of users public keys in their ~/.ssh/authorized_keys.

command="sudo -i -u user-mapped-to-key" ssh-rsa key

You will need to make the user me have the ability to sudo as the other users and you will need to manage me authorized keys file.

Anyway I haven't tested this but in theory something like this should work.