SSH stands for Secure Shell, and refers to a protocol that allows to remotely control and administer a machine using the command line interface (CLI). It is available by default in any terminal on GNU/Linux and macOS. On Windows, you may want to use MobaXterm (after launching it, click on Session then SSH).
The command line interface (CLI) is, in the computer world, the original (and more technical) way of interacting with a computer compared to graphical interface. Command line interfaces are generally said to be more complete, powerful or efficient than a graphical interface, though also more difficult to learn.
1234if you flashed an armbian image)
During the postinstall, you've been asked to choose an administration password. This password becomes the new password for the
admin users. Additionally, the
root SSH login becomes disabled after the postinstall and you should log in using the
admin user !. The only exception is that you may still be able to login using
root from the local network - or from a direct console on the server (this is to cover the event where the LDAP server is broken and the
admin user is unusable).
If you connected as
admin and would like to become
root for convenience (e.g. to avoid typing
sudo in front of every command), you can become
root using the command
sudo su or
If you are installing at home (e.g. on a Raspberry Pi or OLinuXino or old computer):
yunohost-2.local, depending on how many servers are on your network).
yunohost.localand the like do not work, your need to find out the local IP of the server.
If your server is a remote server (VPS), your provider should have communicated you the IP address of the machine
In any cases, if you already configured a domain name pointing to the appropriate IP, it's much better to use
yourdomain.tld instead of the IP address.
The SSH command typically looks like:
# before the postinstall: ssh firstname.lastname@example.org # or after the postinstall: ssh email@example.com # using the domain name instead of the IP (more convenient) ssh firstname.lastname@example.org # using the local domain name instead of the IP (for local access) ssh email@example.com # if you changed the SSH port ssh -p 2244 firstname.lastname@example.org
fail2ban will ban your IP for 10 minutes if you perform 10 failed login attempts. If you need to unban the IP, have a look at the page about Fail2Ban
By default, only the
admin user can log in to YunoHost SSH server.
YunoHost's users created via the administration interface are managed by the LDAP directory. By default, they can't connect via SSH for security reasons. Via the permissions system it is possible to allow the connection in SFTP or if it is really necessary in SSH.
Be careful who you give SSH access to. This increases even more the attack surface available to a malicious user.
Users > Manage groups and permissions.
From here, you can add SFTP or SSH permissions to any user or group.
If you want to add an SSH public key to the user, you have to do it from the command line, as the web interface does not yet offer this feature.
To allow a user or group to access via SFTP or SSH:
# SFTP yunohost user permission add sftp <username> # SSH yunohost user permission add ssh <username>
To remove permission:
# SFTP yunohost user permission remove sftp <username> # SSH yunohost user permission remove ssh <username>
Finally, it is possible to add, delete and list SSH keys, to improve SSH access security, using the commands:
yunohost user ssh add-key <username> <key> yunohost user ssh remove-key <username> <key> yunohost user ssh list-keys <username>
A more extensive discussion about security & SSH can be found on the dedicated page.
Providing a full tutorial about the command line is quite beyond the scope of the YunoHost documentation : for this, consider reading a dedicated tutorial such as this one or this one. But be reassured that you don't need to be a CLI expert to start using it !
yunohost command can be used to administer your server and perform the various actions similarly to what you do on the webadmin. The command must be launched either from the
root user or from the
admin user by preceeding them with
sudo. (ProTip™ : you can become
root with the command
sudo su as
YunoHost commands usually have this kind of structure :
yunohost app install wordpress --label Webmail ^ ^ ^ ^ | | | | category action argument options
Don't hesitate to browse and ask for more information about a given category or action using the the
--help option. For instance, those commands :
yunohost --help yunohost user --help yunohost user create --help
will successively list all the categories available, then the actions available in the
user category, then the usage of the action
user create. You might notice that the YunoHost command tree is built with a structure similar to the YunoHost admin pages.
This command allow you to share with an other person the output of a command.
yunohost tools diagnosis | yunopaste
This command is only available if you have the
VPN Client application installed. You can use it to load a new .cube in case you can't get to the VPN Client interface to do so.
ynh-vpnclient-loadcubefile.sh -u <username> -p <password> -c <path>.cube
If your administration web interface indicates that the API is unreachable, try starting
systemctl start yunohost-api
If you can no longer connect with the user
admin via SSH and via the web interface, the
slapd service may be down, try restarting it:
systemctl restart slapd
If you have manually modified configurations and want to know the changes:
yunohost tools regen-conf --with-diff --dry-run
Found errors? Think you can improve this documentation? Simply click the Edit link at the top of the page, and then the icon on Github to suggest changes.