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  1. @alejandro-martin alejandro-martin revised this gist Jul 19, 2018. 1 changed file with 6 additions and 6 deletions.
    12 changes: 6 additions & 6 deletions multiple-ssh-keys-git.adoc
    View file
    Original file line number Diff line number Diff line change
    @@ -257,11 +257,11 @@ values.

    . Type to configure user _name_:

    git config --global user.name "[email protected]"
    git config --global user.name "YOUR NAME"

    . Type to configure user _email_:

    git config --global user.email "USER NAME"
    git config --global user.email "[email protected]"

    . To see if the *global* fields were correctly configured, use the
    `git config --list` command or check global _Git_ file.
    @@ -272,7 +272,7 @@ this will display a section like:
    +
    ----
    [user]
    name = USER NAME
    name = YOUR NAME
    email = [email protected]
    ----
    +
    @@ -285,11 +285,11 @@ will not appear.

    . Type to configure user _name_:

    git config user.name "[email protected]"
    git config user.name "YOUR NAME"

    . Type to configure user _email_:

    git config user.email "USER NAME"
    git config user.email "[email protected]"

    . To see if the *global* fields were correctly configured, use the
    `git config --list` command or check local _Git_ file:
    @@ -300,7 +300,7 @@ this will display a section like:
    +
    ----
    [user]
    name = USER NAME
    name = YOUR NAME
    email = [email protected]
    ----
    +
  2. @alejandro-martin alejandro-martin created this gist Apr 1, 2018.
    314 changes: 314 additions & 0 deletions multiple-ssh-keys-git.adoc
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    @@ -0,0 +1,314 @@
    = Use Multiple SSH Keys for _Git_ host websites (Github, Gitlab)
    :icons: font

    This is guide about how to configure multiple _SSH_ keys for some _Git_ host
    websites such as _Github_, _Gitlab_, among others.

    == Creating SSH keys

    . Create _SSH_ directory:

    mkdir ~/.ssh

    . Move to created directory:

    cd ~/.ssh

    . To create a _SSH_ key, type:
    +
    ssh-keygen -t rsa -C "[email protected]"
    +
    a message will be displayed:
    +
    Generating public/private rsa key pair.
    Enter file in which to save the key (/home/USER/.ssh/id_rsa):
    +
    You should type someething of the default name of the file to distinguish service,
    such as: `id_rsa_myaccount_github`, `id_rsa_myaccount_gitlab`,
    `id_rsa_mycompanyaccount_gitlab`.
    +
    After this step a _passphrase_ is needed for security, which can be empty.

    . Repeat previous step for every required account.

    . To see if the keys were successful created:
    +
    ls ~/.ssh
    +
    which it is going to print all key files, for example:
    +
    ```
    id_rsa_myaccount_github id_rsa_myaccount_gitlab.pub
    id_rsa_myaccount_github.pub id_rsa_mycompanyaccount_gitlab
    id_rsa_myaccount_gitlab id_rsa_mycompanyaccount_gitlab.pub
    ```

    == Creating _config_ file for manage _SSH_ keys

    . To create `config` file:

    touch ~/.ssh/config

    . Edit the file to configure _domains_ for the keys:
    +
    nano ~/.ssh/config
    +
    for example, if three accounts were added, should look like this:
    +
    ```
    # github account
    Host github.com
    HostName github.com
    PreferredAuthentications publickey
    IdentityFile ~/.ssh/id_rsa_myaccount_github

    # gitlab account
    Host gitlab.com
    HostName gitlab.com
    PreferredAuthentications publickey
    IdentityFile ~/.ssh/id_rsa_myaccount_gitlab

    # gitlab company account
    Host gitlab.my_company.com
    HostName gitlab.my_company.com
    PreferredAuthentications publickey
    IdentityFile ~/.ssh/id_rsa_mycompanyaccount_gitlab
    ```

    . Save file and exit.

    === Using two accounts from the same server (website) [Optional]

    A new host has to be created.

    . Create a new entry on the `~/.ssh/config` file(example with _Github_):

    ```
    Host other.github.com
    HostName github.com
    PreferredAuthentications publickey
    IdentityFile ~/.ssh/id_rsa_otheraccount_github
    ```

    where `other.github.com` is the alias for the host, although the server(`HostName`) is
    `github.com`.
    The `IdentityFile` option points to a (previously) created key file configured with
    the required account.

    After this, a custom url can be used to clone the project.

    git clone [email protected]:USER/REPOSITORY.git

    where `other.github.com` is the previously created domain.

    == Configure _SSH_ on Repository site

    To configure ssh on each repository website:

    . Copy the content of the `id_rsa_X.pub` with `xclip` command(may not be installed)
    to the clipboard(where `id_rsa_X.pub` is the wanted key file):
    +
    xclip -sel clip < ~/.ssh/id_rsa_X.pub
    +
    (content also can also be manually copied from the `*.pub` file)

    . Paste the content on the repository site, check next section.

    === Configure _SSH_ on Github

    . Go to https://github.com.

    . Go to Profile _Settings_ > _SSH and GPG Keys_ > click on button _New SSH Key_.

    . On _Title_ add a descriptive label, such as the _hostname_ of the device...

    . On the _Key_ field past the clip content with the key.

    . Finally click on _Add SSH key_ and after that the site ask for the user password.

    === Configure _SSH_ on Gitlab

    . Go to https://gitlab.com.

    . Go to Profile _Settings_ > _SSH Keys_.

    . On the _Key_ field past the clip content with the key.

    . On _Title_ add a descriptive label, such as the _hostname_ of the device...

    . Finally click on _Add key_.


    == Testing SSH Keys

    . Type(substitute `HOST` with the desired one(_github_, _gitlab_, ...)):
    +
    ssh -T [email protected]
    +
    a warning will appear, accept it with `yes`:
    +
    ```
    The authenticity of host 'HOST.com (IP ADDRESS)' can't be established.
    RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.
    Are you sure you want to continue connecting (yes/no)?
    ```
    +
    A successful message will appear:
    +
    .. For _Github_:
    +
    ```
    Hi USERNAME! You've successfully authenticated, but GitHub does not
    provide shell access.
    ```
    +
    .. For _Gitlab_:
    +
    ```
    Welcome to GitLab, USERNAME!
    ```

    === Delete _SSH_ Cache and add Keys

    If the _SSH_ does not work, maybe the keys need to be added with `ssh-add` command

    . First delete keys cache:

    ssh-add -D
    +
    if a message appear:
    +
    Could not open a connection to your authentication agent.
    +
    use this command and after that retry:
    +
    eval `ssh-agent -s`

    . Add key file with `ssh-add` command:

    ssh-add ~/.ssh/id_rsa_file

    . To see added keys, type:
    +
    ssh-add -ld
    +
    and something such as this will be displayed:
    +
    ```
    2048 SHA256:DXlgYQo1o/65JQCSYQo/L4RRP4i+wTouyEetkOIcn/o EMAIL_1 (RSA)
    2048 SHA256:4FPtZYDtHipZeHqP9KNB3Wslz9L5q/JoAGT3g/NW3O8 EMAIL_2 (RSA)
    2048 SHA256:tXCoBI2dMtTFhUhE5oBT+XwwkrhkorkOHbSc1J22urQ EMAIL_3 (RSA)
    ```

    . Retry testing connection.

    == Using SSH keys

    To use a git repository with the _SSH_, this url style has to be used for the
    repository:

    git@HOST:USERNAME/REPOSITORY.git

    where `HOST` is the configured domain, which can be _github_, _gitlab_ or a
    personalized one.

    If project origin is already configured with HTTPS, it has to be changed to the
    SSH url style (check next section).

    WARNING: If you want to use the HTTPS url, other steps will be required.

    === Change HTTPS url to SSH url [Optional]

    . List existing remotes in order to get the name of the repository:

    git remote -v

    . Change remote url, substitute HOST for server domain or a previously create
    custom HOST:

    git remote set-url origin git@HOST:USERNAME/REPOSITORY.git

    NOTE: It can be used the same method to change from SSH to HTTPS.

    == Important: About `git config` user _name_ and _email_

    In spite _SSH_ keys were configured for the access, the _Git_ user _name_
    and _email_ need to be configured, because these will be associated to the
    _commits_.

    To see actual configuration, type:

    git config --list

    If global user _name_ and _email_ were configured will be displayed at the beginning,
    if not, these values will not appear.

    NOTE: If the command was run on a repository and this one has a local
    user _name_ and _email_ configured, these values will be displayed at the end of
    configuration.

    === Configure user _name_ and _email_ on all repositories (globally)

    IMPORTANT: You may want to configure the most used user _name_ and _email_ globally,
    but watch out since every commit with not _local configuration_ will use these
    values.

    . Go to the root directory of the repository.

    . Type to configure user _name_:

    git config --global user.name "[email protected]"

    . Type to configure user _email_:

    git config --global user.email "USER NAME"

    . To see if the *global* fields were correctly configured, use the
    `git config --list` command or check global _Git_ file.
    +
    nano ~/.gitconfig
    +
    this will display a section like:
    +
    ----
    [user]
    name = USER NAME
    email = [email protected]
    ----
    +
    NOTE: If the _user name_ or the _user email_ were not configured this section
    will not appear.

    === Configure user _name_ and _email_ on a unique repository (locally)

    . Go to the root directory of the repository.

    . Type to configure user _name_:

    git config user.name "[email protected]"

    . Type to configure user _email_:

    git config user.email "USER NAME"

    . To see if the *global* fields were correctly configured, use the
    `git config --list` command or check local _Git_ file:
    +
    nano ./.git/config
    +
    this will display a section like:
    +
    ----
    [user]
    name = USER NAME
    email = [email protected]
    ----
    +
    NOTE: If the _user name_ or the _user email_ were not configured this section
    will not appear.

    == References

    * https://docs.gitlab.com/ee/ssh/
    * https://gist.github.com/jexchan/2351996
    * https://help.github.com/articles/setting-your-commit-email-address-in-git/