SSH Access

Warning

As of now (July 2023), ssh access via gate.biologie.hu-berlin.de requires a ssh key.

SSH basics

SSH from inside the ITB

ssh perry@compute1

or

ssh perry@compute1.itb.biologie.hu-berlin.de

SSH from outside the ITB (needs an ssh key!)

ssh perry@gate.biologie.hu-berlin.de

This will relay you to the internal ITB server ssh.itb.biologie.hu-berlin.de which you can use to access other servers. You should not run any computational intense simulations here.

SSH keys

Create a ssh key like this:

ssh-keygen -a 100 -t ed25519

The -a 100 increases the brute-force resistance (the default is -a 16) while -t ed25519 uses a more modern algorithm as the default that also results in a smaller public key to copy.

The command will ask you to provide a password and then generates two files. ~/.ssh/id_ed25519 and ~/.ssh/id_ed25519.pub. The first file is the private key (which is in turn encrypted with the password given). It should never leave your computer!

The .pub file is the public key, which you should append to the ~/.ssh/authorized_keys file in the computer that you want to log in to. (In this case: Your ITB home folder on any of the ITB computers.)

Setting up a tunnel

Note

The following is only useful when no OpenVPN connection is established and you are using an ssh key to log in.

When accessing the ITB from home, the following command is helpful:

ssh -J perry@gate.biologie.hu-berlin.de perry@compute1.itb.biologie.hu-berlin.de

It is useful to add this command to one's ssh configuration or to define a bash alias in one's .bashrc:

alias itbssh='ssh -J schuppner@gate.biologie.hu-berlin.de'

# later
itbssh compute1