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Using The Lonestar6 Cluster

Using The Lonestar6 Cluster

This page is a quick start for using the Lonestar6 cluster at TACC.

The Lonestar6 User Guide

For complete up-to-date information, always see: TACC's Lonestar User Guide

Logging in

ssh <my_user_name>@ls6.tacc.utexas.edu #if this doesn't work: ssh -m hmac-sha2-512 <my_user_name>@ls6.tacc.utexas.edu

Setting up up a profile

There are many flavors of Linux/Unix shells. The default for TACC's Linux (and most other Linuxes) is bash (bourne againshell), which we will use throughout.

Whenever you login via an interactive shell as you did above, a well-known script is executed by the shell to establish your favorite environment settings. We've set up a common profile for you to start with that will help you know where you are in the file system and make it easier to access some of our shared resources. To set up this profile, do the following steps after logging in:

Copy a preconfigured "profile" to use with your account

cdh mv ~/.profile ~/.profile.old cp /work2/projects/BioITeam/projects/courses/Core_NGS_Tools/tacc/bashrc.corengs.ls6.light_bg ~/.profile echo "export PATH=\$PATH:/work2/projects/BioITeam/common/bin/" >> ~/.profile chmod 600 .profile source .profile ls -a

The chmod 600 .profile command marks the file as readable/writable only by you. The .profile script file will not be executed unless it has these permissions settings. Note that the well-known filename is .profile (or .profile_user on some systems), which is specific to the bash shell.

Notice that when you do a normal ls to list the contents of your home directory, this file doesn't appear. That's because it's a hidden "dot file" – a file that has no filename, only an extension. To see these hidden files, use the -a (all) switch for ls.

Transferring Files to and from Lonestar

Obtaining the Path

It's a good idea to open 2 terminals for transferring files.

  • One logged in on Lonestar with the current directory set to where you want to transfer files to or from

  • One on your computer with the current directory set to where you want to transfer files to or from

On Lonestar:

Go to the directory where you want your files to be or where you want to copy from.

Type

To find the absolute path, needed to pull or push files from/to Lonestar
pwd

This gives the absolute path to your directory. It might start with "home" or "work" depending on what directory you're in.

Mac/Linux

Transferring files to Lonestar

On your computer's side:

Go to the directory where you want to copy files from.

scp stuff.fastq my_user_name@ls6.tacc.utexas.edu:/home/.../ #If getting the correct MAC on input error, add an extra option to the scp command: scp -o "MACs=hmac-sha2-512" stuff.fastq my_user_name@ls6.tacc.utexas.edu:/home/.../

Replace the "/home/.../" with the "pwd" information obtained earlier.

This command would transfer "stuff.fastq" in your current directory to a specified directory on Lonestar.

Transferring files from Lonestar

On your computer's side:

Go to the directory where you want to copy files to.

scp my_user_name@ls6.tacc.utexas.edu:/home/.../stuff.fastq ./ #If getting the correct MAC on input error, add an extra option to the scp command: scp -o "MACs=hmac-sha2-512" my_user_name@ls6.tacc.utexas.edu:/home/.../stuff.fastq ./

Replace the "/home/..." with the "pwd" information obtained earlier.

This command would transfer "stuff.fastq" from the specified directory on Lonestar to your current directory on your computer.

Copying Directories

Sometimes you may want to transfer more than one file.

If you wanted to transfer a directory, use the -r option like so:

scp -r my_folder my_user_name@ls6.tacc.utexas.edu:/... #If getting the correct MAC on input error, add an extra option to the scp command: scp -ro "MACs=hmac-sha2-512" my_folder my_user_name@ls6.tacc.utexas.edu:/...

You can also transfer directories from Lonestar in the same manner:

scp -r my_user_name@ls6.tacc.utexas.edu:/home/.../my_folder ./ #If getting the correct MAC on input error, add an extra option to the scp command: scp -ro "MACs=hmac-sha2-512" my_user_name@ls6.tacc.utexas.edu:/home/.../my_folder ./

Windows

SSH Secure File Transfer (Windows) is available as part of the SSH Secure Shell client which can be downloaded from Bevoware. You can also use winscp (free to download).

Modules

Modules are programs or sets of programs that have been set up to run on TACC. They make managing your computational environment very easy. All you have to do is load the modules that you need and a lot of the advanced wizardry needed to set up the linux environment has already been done for you. New commands just appear.

To see all modules available in the current context, type:

module avail

If there are many modules on a system, it can be difficult to see what modules are available to load. To display a concise listing:

module overview
module load gatk

Why not load all the modules by default? Well, you actually may want to add many of the moduels that you encounter in later tutorials to be loaded on login. The reason they are not loaded by default is to keep things lean for those people simulating hurricanes who don't want to load Bioperl every time they log in. Occasionally two different modules also don't play nice together and you will get messages that you have to "swap" one for another.

To unload any modules, type:

module unload gatk

Since module avail only shows modules in the current context (i.e. based on your currently loaded modules), to see all possible modules use:

module spider <freetext>

If you specify some text for <freetext>, you'll see all modules with that text anywhere in their title or description. For example, try to find the transcriptome assembler Trinity.

Biocontainers

BioContainers is a community-driven project that provides the infrastructure and basic guidelines to create, manage and distribute Bioinformatics containers with special focus in Proteomics, Genomics, Transcriptomics and Metabolomics. BioContainers is based on the popular frameworks of Docker.

What is a container?

image-20250609-145015.png

  • A container packages up code and all its dependencies so the application runs quickly and reliably from one computing environment to another.

  • Multiple containers can run on the same machine and share the OS kernel with other containers, each running as isolated processes in user space, hence are lightweight and have low overhead.

  • TACC uses apptainer, a software solution to execute containers.

  • TACC has many containers already available. Most bioinformatics tools can be found on Biocontainers. We can load them by doing this:

module load biocontainers
module load multiqc

 

Now let's go on to look at the directory structure at Lonestar6.