tldr/pages/common/ssh.md

# ssh

> Secure Shell is a protocol used to securely log onto remote systems.
> It can be used for logging or executing commands on a remote server.

- Connect to a remote server:

`ssh {{username}}@{{remote_host}}`

- Connect to a remote server with a specific identity (private key):

`ssh -i {{path/to/key_file}} {{username}}@{{remote_host}}`

- Connect to a remote server using a specific port:

`ssh {{username}}@{{remote_host}} -p {{2222}}`

- Run a command on a remote server:

`ssh {{remote_host}} {{command -with -flags}}`

- SSH tunneling: Dynamic port forwarding (SOCKS proxy on localhost:9999):

`ssh -D {{9999}} -C {{username}}@{{remote_host}}`

- SSH tunneling: Forward a specific port (localhost:9999 to slashdot.org:80) along with disabling pseudo-[t]ty allocation and executio[n] of remote commands:

`ssh -L {{9999}}:{{slashdot.org}}:{{80}} -N -T {{username}}@{{remote_host}}`

- SSH jumping: Connect through a jumphost to a remote server (Multiple jump hops may be specified separated by comma characters):

`ssh -J {{username}}@{{jump_host}} {{username}}@{{remote_host}}`

- Agent forwarding: Forward the authentication information to the remote machine (see `man ssh_config` for available options):

`ssh -A {{username}}@{{remote_host}}`