Private repo can't read with Git on composer installation on CentOS server

Question

I'm trying to install some private repos via Composer in my Laravel application using deployer, I've created my github SSH alias's and added my keys with ssh-add -k path-to-key and have added them to the individual private repos, it seems that the server is still struggling to access these, my repos of my project are included as such:

"repositories": [
    {
      "type": "vcs",
      "url": "git@my-alias:company/my-package.git"
    }
]

My config for Git on my server is...

Host my-alias github.com
Hostname github.com
IdentityFile /root/.ssh/my_package_id_rsa

I have multiple hosts in there, the above is just one of 6. The error when composer install is attempted through Deployer is...

ERROR: Repository not found.

fatal: Could not read from remote repository.

Please make sure you have the correct access rights

and the repository exists.

When I run ssh -T [email protected] on the server I get:

Hi company/my-package! You've successfully authenticated, but GitHub does not provide shell access.

So I would've thought the server would be able to read my composer file and clone the repo successfully?

Answer 1

If ssh -T [email protected] works on the server, it means the default ~/.ssh/id_rsa is working, not /root/.ssh/my_package_id_rsa

If you want to test access with /root/.ssh/my_package_id_rsa, you would need to type:

sudo ssh -Tv my-alias

"sudo" because otherwise /root/.ssh would not be accessible anyway.
Which means the ssh config file must be in /root/.ssh/config
And the Host entry must be my-alias. Not "my-alias github.com"

That would also means the composer install would have to be executed as root (sudo), which is not a best practice.