Cluster Login - nthu-ioa/cluster GitHub Wiki

To set up your account and connect to the cluster for the first time, see this page.

Once your account is set up, connect to the cluster using: ssh [email protected]

[!IMPORTANT] To protect against brute-force password attacks, your IP address will be temporarily banned if you type the wrong password 5 times in a short period. This ban will last for about 15 minutes, so just wait, then try again.

SSH keys

Using SSH keys (rather than just typing your password) makes your connection more secure. We prefer everyone to use SSH keys if possible. See our guide to setting up ssh keys.

SSH configuration

You can customize ssh connections to individual ssh hosts by adding entries in your ~/.ssh/config file. The following are some useful things you can do with that.

[!Note] ~/.ssh/config must have restricted write permissions: chmod 644 ~/.ssh/config. If it has other permissions, nothing will work.

Shortcut

Typing the full address of the cluster each time you want to connect is not necessary. You can define a shortcut to connect to fomalhaut by adding the following lines to ~/.ssh/config:

Host fomalhaut
HostName fomalhaut.astr.nthu.edu.tw
User your_username_here

After adding these lines, you can connect by typing ssh fomalhaut, which is much shorter than ssh [email protected].

Timeouts

If you experience frequent timeouts, define a Host in ~/.ssh/config as above and add the following two lines underneath Host fomalhaut:

ServerAliveInterval 10
ServerAliveCountMax 120

If you prefer, you can extend the timeouts for all hosts in your ~/.ssh/config by adding these lines to a generic host at the top of the file, as follows:

Host *
ServerAliveInterval 10
ServerAliveCountMax 120