git ssh authorisation error when accessing bitbucket repo multiple keys

Question

I have multiple ssh keys, using one key for one project. I have successfully assigned the public ssh keys to the relevant repositories inside my bitbucket account.

They are stored in the following location:

~/.ssh/rsa_generic_repos
~/.ssh/rsa_generic_repos.pub
~/.ssh/rsa_project1
~/.ssh/rsa_project1.pub

I then add these keys to my ssh-agent before attempting any git access:

ssh-add ~/.ssh/rsa_generic_repos
ssh-add ~/.ssh/rsa_project1

ssh-add -l - Displays:

4096 SHA256:XXXXXXXXXXXXXXXXXXXXXXXXXXX/XXXXXXXXXXXX Generic Repo Key (RSA)
4096 SHA256:XXXXXXXXXXXXXXXXXXXXXXXXXXX/XXXXXXXXXXXX Project 1 Key (RSA)

My Problem:

This works correctly (clones the repo):

git clone git@bitbucket.org:Myusername/generic-repo.com.git

This does not work:

git clone git@bitbucket.org:Myusername/project1.com.git

Error:

Cloning into 'project1'...
repository access denied. deployment key is not associated with the requested repository.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights and the repository exists.

Yet if I run:

ssh-add -D
ssh-add ~/.ssh/rsa_project1
git clone git@bitbucket.org:Myusername/project1.com.git

It successfully clones the repo which it previously wouldn't. This suggests firstly that the public key is set up on bitbucket correctly and that the ssh daemon is not attempting to use any ssh key other than the first entry therefore resulting in the above error.

If anyone could help me with a way to get ssh to go through all the keys stored in the ssh-agent session I would be tremendously grateful.

Thank you for your help and time.

Answer 1

The proper way to use multiple ssh keys would be to ~/.ssh/config file, as I describe here

Host bbgeneric
    Hostname bitbucket.org
    IdentityFile ~/.ssh/rsa_generic_repos
    User git

Host bbproject1
    Hostname bitbucket.org
    IdentityFile ~/.ssh/rsa_project1
    User git

And you would use ssh url like

bbgeneric:Myusername/generic-repo.com.git
bbproject1:Myusername/project1.com.git

Using one deployment key is indeed easier, but I wanted to illustrate the config ssh feature which allows you to use any number of keys.

Answer 2

Thanks to VonC's answer.
Here is the working solution I could have used:

~/.ssh/config

Host bitbucket-generic-repos
    HostName bitbucket.org
    IdentityFile ~/.ssh/rsa_generic_repos

Host bitbucket-project1
    HostName bitbucket.org
    IdentityFile ~/.ssh/rsa_project1

The following command gave me an error:

git clone git@bitbucket.org:<MyUsername>/project1.com.git

Replacing the bitbucket.org with the ssh alias defined in ~/.ssh/config in the git command results in the desired behaviour with no errors:

git clone git@bitbucket-project1:<MyUsername>/project1.com.git (works!)
git clone git@bitbucket-generic-repos:<MyUsername>/project1.com.git (also works!)