Connecting to LUMI¶

This page gives you more details on how to configure your machine to access LUMI. However, it does not cover the first necessary steps to connect to LUMI like how to generate a key pair and setup your public SSH key on your MyAccessID profile. Instruction on how to do that can be found here.

From the command line¶

Connecting to LUMI via the command line is possible from all major OS. Once you have generated your key pair and setup your public SSH key on your MyAccessID profile, you can connect with

ssh -i<path-to-private-key> <username>@lumi.csc.fi

where you have to replace <path-to-private-key> and <username> with the appropriate values. You should have received your user name via email. If not, please contact the support.

You will be prompted for the passphrase of the SSH key which is the one you entered when you generated the key. When you connect for the first time, you will also be asked to check the host key fingerprint of the system and need to type yes in order to accept it. The fingerprint of the LUMI login nodes are listed in the table below.

Hash type	Fingerprint
MD5	`28:2a:38:71:b0:a6:6b:90:0e:1b:a1:9d:ca:ec:94:20`
SHA256	`hY4mnRCYb8bRchTnVcFo7SqoHHHEsUh9Ym38F4sHN1Y`

Add your key to your agent¶

If you chose a strong passphrase for your key, what you should have done, it might be painful to enter you passphrase for every connection. To avoid the pain, you can use an SSH agent to remember the passphrase for you.

The first step in to ensure the SSH agent is running. For that run the command

eval "$(ssh-agent -s)"

The second step is to add your private key to your agent with the command

ssh-add <path-to-private-key>

you will then be asked for your passphrase and now, you should no longer have to enter your passphrase every time you connect to LUMI.

Add LUMI to your SSH configuration¶

In the previous section, we have discussed how to add your key to the agent and thus avoid having to enter your password. You can also create an SSH configuration for LUMI on your machine that will act as a shortcut. This is achieved by editing the .ssh/config file and by adding the following lines

Host lumi
  HostName lumi.csc.fi
  User <username>
  IdentityFile <path-to-private-key>

Once you added this line to your SSH configuration file, you can connect using the following command

ssh lumi

This configuration will also influence the behaviour of any program that uses SSH git, scp, and rsync.

Troubleshooting¶

If you have trouble connecting to LUMI, you can run the SSH client with verbose output enabled.

ssh -vvv -i<path-to-private-key> <username>@lumi.csc.fi

If you are unable to connect and you contact the support, we recommend that you provide the output of this command.