Create an SSH key pair for use with Bianca¶

This page describes how to create and use an SSH key for the Bianca cluster.

Procedure¶

This procedure will fail if:

You are outside of the university networks, see how to get inside the university networks. This video shows it will fail when being outside of the university networks
You use Ubuntu 24.04 Noble, as demonstrated by this video, where a password is still requested after doing this procedure on Rackham

Here is the procedure:

Add the content of your public key id_ed25519_key.pub to $HOME/.ssh/authorized_keys. You can not use the same command ssh-copy as in the case for Rackham, i.e. you have to manually bring the key on Bianca. If you paste it, make sure it is in one line, not wrapped/split over multiple lines.
Make sure the permissions look something like this:

ls -ld .ssh
drwx--S--- 2 user user 4096 May  7  2019 .ssh

ls -l .ssh
total 1
-rw-r----- 1 user user 743 May  7  2019 authorized_keys

Then log in to Bianca via the console using an SSH key:

ssh -A user-sensXXXXX@bianca.uppmax.uu.se

To debug, run with -vv

...
debug1: Requesting authentication agent forwarding.
debug2: channel 1: request auth-agent-req@openssh.com confirm 0
...

debug1: client_input_channel_open: ctype auth-agent@openssh.com rchan 2 win 65536 max 16384
debug1: client_request_agent: bound agent to hostkey
debug2: fd 8 setting O_NONBLOCK
debug1: channel 2: new [authentication agent connection]
debug1: confirm auth-agent@openssh.com
Last login: Tue Jul 11 18:44:21 2023 from 172.18.144.254
 _   _ ____  ____  __  __    _    __  __
| | | |  _ \|  _ \|  \/  |  / \   \ \/ /   | System:    sens2017625-bianca
| | | | |_) | |_) | |\/| | / _ \   \  /    | User:      user
| |_| |  __/|  __/| |  | |/ ___ \  /  \    |
 \___/|_|   |_|   |_|  |_/_/   \_\/_/\_\   |

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