I'm new to git.
I need to use public key to push changes from my repo. How can I administer users ? If i want delete an user ?
Is The public key management the only way to administer a git system ?
If you are using the ssh protocol to access your git repo, then yes, you need to add a public key to the ~/.ssh/authorized_keys
of the user account managing said repos.
But ssh is hardly the only protocol available to access your repo: see the Pro Git book: a simple shared path (local protocol) can be enough at first (no server, no key, but also no authentication).
Note: as explained in this Gitolite man page "Gitolite without ssh", Gitolite manages only authorization, not authentication.
You can use ssh for its authentication capabilities.