Getting Logged In - statonlab/UTIA_Computational_Resource Wiki

In this section, we will discuss how to get access to the UTIA Computational Resource servers and how to login once you have that information.

System Administration Notes

  1. Dr. Staton or Matt will send an OIT help ticket to add you to the statonutia group. This recommendation matches the following template:
I need an LDAP admin to add trickman (Tara Rickman) to the POSIX group statonutia so that she can access my research compute server. (Sys admin for server is George Butler).
Thanks!

Once you are added your normal UTK username and password will be used to login.

  1. Now you must set posixAccount attribute and associated metadata on your LDAP entry - this can be done by visiting https://setuplinux.utk.edu/. Make sure you click "Create Account" so you can access the server.

  2. Once you are able to login, update your ~/.bash_profile using either nano or vim to include:

# .bash_profile

# Get the aliases and functions
if [ -f ~/.bashrc ]; then
	. ~/.bashrc
fi

# User specific environment and startup programs

export SPACK_ROOT=/pickett_shared/spack
PATH=$PATH:$HOME/bin:$SPACK_ROOT/bin
. $SPACK_ROOT/share/spack/setup-env.sh

exec newgrp statonutia

How to Login

First, install and activate UTK's VPN Software Pulse Secure, found at https://help.utk.edu/kb/index.php?func=show&e=2712. You will be unable to login to either server without an active VPN.

Now open a terminal window and run one of the following, based on which server you plan to login to:

Centaur

ssh <your_username>@centaur.ag.utk.edu

Sphinx

ssh <your_username>@sphinx.ag.utk.edu

Establish host authenticity

The first time you attempt to login to both servers, you will get a message similar to the following:

The authenticity of host 'centaur.ag.utk.edu (160.36.238.143)' can't be established.
ECDSA key fingerprint is <string_of_numbers>.
Are you sure you want to continue connecting (yes/no/[fingerprint])

This is normal. Type in yes to move on to the next step. From this point on the server you logged into will have its fingerprint stored in your computer, so you will not see this message again unless it is removed.

A note on passwords

When you login to one of the servers, it will ask you for your password. As you type in the password, you will notice that no characters appear in the prompt. This, again, is normal; type in your password as normal and press Enter/Return when ready. This is for security purposes and protects your password. If successfully typed, you will be given access to the server.

If you get locked out...

If you provide an incorrect or misspelled group to the newgrp command in your ~/.bash_profile file, you will not be able to access the servers. You don't need to panic - this is something you can fix on your own.

First, to figure out where the error in the newgrp command is, run the following command to view the ~/.bash_profile command:

ssh <user_name>@centaur.ag.utk.edu 'cat ~/.bash_profile'

An example is that this page used to contain the deprecated group statonrg as the group, rather than the correct statonutia group name. If this has happened to you, you can use this same idea to replace the incorrect group name with the updated name with the sed command:

ssh <user_name>@centaur.ag.utk.edu 'sed -i 's/statonrg/statonutia/g' ~/.bash_profile'