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TACC storage areas and Linux commands to access data (all commands to be executed at TACC except laptop-to-TACC copies, which must be executed on your laptop) |
Local file systems
There are 3 local file systems available on any TACC compute cluster (Lonestar5stampede2, stampede2 lonestar5, etc.), each with different characteristics. All these local file systems are very fast and set up for parallel I/O (Lustre file system).
On ls5 stampede2 these local file systems have the following characteristics:
Home | WorkWork2 | Scratch | |
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quota | 10 GB | 1024 GB = 1 TB | 2+ PB (basically infinite) |
policy | backed up | not backed up, not purged | not backed up, purged if not accessed recently (~10 days) |
access command | cd | cdwcdw2 | cds |
environment variable | $HOME | $STOCKYARD (root of the shared Work file system) $WORK $WORK2 (different sub-directory for each cluster) | $SCRATCH |
root file system | /home | /workwork2 | /scratch |
use for | Small files such as scripts that you don't want to lose. | Medium-sized artifacts you don't want to copy over all the time. For example, custom programs you install (these can get large), or annotation file used for analysis. | Large files accessed from batch jobs. Your starting files will be copied here from somewhere else, and your final results files will be copied elsewhere (e.g. stockyard, corral, or your BRCF POD). |
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Code Block |
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--------------------- Project balances for user abattenh ---------------------- | Name Avail SUs Expires | Name Avail SUs Expires | | genomeAnalysis 673 2021-03-31 | BioinformaticsResour 100 2020-06-30 | | UT-2015-05-18 1000 2021-03-31 | DNAdenovo 4969 2021-03-31 | | CancerGenetics 4856 2020-09-30 | A-cm10 8867 2020-12-31 | ------------------------ Disk quotas for user abattenh ------------------------ | Disk Usage (GB) Limit %Used File Usage Limit %Used | | /home1 0.0 10.0 0.10 153 1000000 0.02 | | /workwork2 614.5 1024.0 60.01 61094 3000000 2.04 | | /scratch 2676.6 0.0 0.00 32442 0 0.00 | ------------------------------------------------------------------------------- |
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When you first login, you start in your home directory. Use these the cd, cdw2 and cds commands to change to your other file systems. Notice how your command prompt helpfully changes to show your location.
Code Block | ||||
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cdwcdw2 cds cd |
Tip |
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The cd (change directory) command with no arguments takes you to your home directory on any Linux/Unix system. The cdw cdw2 and cds commands are specific to the TACC environment. |
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TACC compute clusters now share a common Work file system called stockyard. So files in your Work area do not have to be copied, for example from ls5 to stampede2 to ls5 – they can be accessed directly from either cluster.
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- $STOCKYARD - This refers to the root of your shared Work area
- e.g. /work/01063/abattenh (should be changed to /work2/01063/abattenh soon)
- e.g. /work/01063/abattenh (should be changed to /work2/01063/abattenh soon)
- $WORK or $WORK2 - Refers to a sub-directory of the shared Work area that is different for different clusters, e.g.:
- /work/01063/abattenh/lonestar on ls5
- /workwork2/01063/abattenh/stampede2 on stampede2
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ls /workwork2/projects/BioITeam |
Files we will use in this course are in a sub-directory there. The $CORENGS environment variable set in your login profile refers to this path.
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echo $CORENGS ls /workwork2/projects/BioITeam/projects/courses/Core_NGS_Tools |
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corral is a gigantic (multiple PB) storage system (spinning disk) where researchers can store data. UT researchers may request up to 5 TB of corral storage through the normal TACC allocation request process. Additional space on corral can be rented for ~$85~$80/TB/year.
The UT/Austin BioInformatics Team also has an older, common directory area on corral.
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ls /corral-repl/utexas/BioITeam |
A couple of things to keep A couple of things to keep in mind regarding corral:
- corral is a great place to store data in between analyses.
- Store your permanent, original sequence data on corral
- Copy the data you want to work with from corral to $SCRATCH
- Run your analyses (batch jobs)
- Copy your results back to corral
- Occasionally corral can become unavailable. This can cause any command to hang that tries to access corral data!
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Once that data is staged to the ranch disk it can be copied to other places. However, the ranch file system is not mounted as a local file system from the stampede2 or ls5 clusters. So remote copy commands are always needed to copy data to and from ranch (e.g. scp, rsync).
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- original – for original sequencing data (compressed FASTQ files)
- sub-directories named, for example, by year_month.<project_name>
- aligned – for alignment artifacts (BAM files, etc)
- sub-directories named, e.g., by year_month.<project_name>
- analysis – further downstream analysis
- reasonably named sub-directories, often by project
- genome refs – reference genomes and other annotation files used in alignment and analysis
- sub-directories for different reference genomes
- e.g. ucsc/hg19, ucsc/sacCer3, mirbase/v20
- code – for scripts and programs you and others in your organization write
- ideally maintained in a version control system such as git, subversion or cvs.
- easiest to name sub-directories for people.
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mkdir -p $WORK$SCRATCH/archive/original/20202021.core_ngs cd $WORK$SCRATCH/archive/original/20202021.core_ngs wget |
Here are two web links:
- httphttps://web.corral.tacc.utexas.edu/BioITeamBioinformaticsResource/CoreNGS/yeast_stuff/Sample_Yeast_L005_R1.cat.fastq.gzhttp
- https://web.corral.tacc.utexas.edu/BioinformaticsResource/BioITeamCoreNGS/yeast_stuff/Sample_Yeast_L005_R2.cat.fastq.gz
Right-click (Windows) or Control+click (Mac) on the 1st link in your browser, then select "Copy link location" from the menu. Now go back to your Terminal. Put your cursor after the space following the wget command then either right-click (Windows), or Paste (Command-V on Mac, Control-V on Windows). The command line to be executed should now look like this:
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wget http://web.corral.tacc.utexas.edu/BioITeamBioinformaticsResource/CoreNGS/yeast_stuff/Sample_Yeast_L005_R1.cat.fastq.gz |
Now press Enter to get the command going. Repeat for the 2nd link. Check that you now see the two files (ls).
Copy from a corral location - cp or rsync
Suppose you have a corral allocation or stockyard area where your organization keeps its data, and that the sequencing data has been downloaded there. You can use various Linux commands to copy the data locally from there to your $SCRATCH area.
cp
The cp command copies one or more files from a local source to a local destination. It has the most common form:
cp [options] <source file 1> <source file 2> ... <destination directory>/
Make a directory in your scratch area and copy a single file to it. The trailing slash ( / ) on the destination says it is a directory.
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mkdir -p $SCRATCH/data/test1
cp $CORENGS/misc/small.fq $SCRATCH/data/test1/
ls $SCRATCH/data/test1
# or..
mkdir -p ~/scratch/data/test1
cd ~/scratch/data/test1
cp $CORENGS/misc/small.fq .
ls |
Tip |
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By default wget creates a file in the current directory matching the last component of the URL (e.g. Sample_Yeast_L005_R1.cat.fastq.gz here). You can change the copied file name with wget's -O option. Also note that if you execute the same wget more than once, subsequent local files will be named with a .1, .2, etc. suffix. |
Copy from a corral location - cp or rsync
Suppose you have a corral allocation or stockyard area where your organization keeps its data, and that the sequencing data has been downloaded there. You can use various Linux commands to copy the data locally from there to your $SCRATCH area.
cp
The cp command copies one or more files from a local source to a local destination. It has the most common form:
cp [options] <source file 1> <source file 2> ... <destination directory>/
Make a directory in your Scratcharea and copy a single file to it. The trailing slash ( / ) on the destination says the destination is a directoryCopy an entire directory to your scratch area. The -r argument says "recursive".
Code Block | ||||
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mkdir -p $SCRATCH/data/test1 cds cd data cp -r $CORENGS/general/ general/ |
Exercise: What files were copied over?
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ls general |
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BEDTools-User-Manual.v4.pdf SAM1.pdf SAM1.v1.4.pdf |
local rsync
...
rsync is a very complicated program, with many options (http://rsync.samba.org/ftp/rsync/rsync.html). However, if you use the recipe shown here for directories, it's hard to go wrong:
rsync -avW local/path/to/source_directory/ local/path/to/destination_directory/
Both the source and target directories are local (in some file system accessible directly from ls5). Either full or relative path syntax can be used for both. The -avP options above stand for:
...
- -p – preserve file permissions
- -t – preserve file times
- -l – copy symbolic links as links
- -r – recursively copy sub-directories
cp $CORENGS/misc/small.fq $SCRATCH/data/test1/
ls $SCRATCH/data/test1
# or..
mkdir -p ~/scratch/data/test1
cd ~/scratch/data/test1
cp $CORENGS/misc/small.fq .
ls |
Copy an entire directory to your Scratch area. The -r option says "recursive".
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mkdir -p $SCRATCH/data
cds
cd data
cp -r $CORENGS/general/ general/ |
Exercise: What files were copied over?
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ls general |
Expand | ||
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BEDTools-User-Manual.v4.pdf SAM1.pdf SAM1.v1.4.pdf |
local rsync
The rsync command is typically used to copy whole directories. What's great about rsync is that itonly copies what has changed in the source directory. So if you regularly rsync a large directory to TACC, it may take a long time the 1st time, but the 2nd time (say after downloading more sequencing data to the source), only the new files will be copied.
rsync is a very complicated program, with many options (http://rsync.samba.org/ftp/rsync/rsync.html). However, if you use the recipe shown here for directories, it's hard to go wrong:
rsync -avW local/path/to/source_directory/ local/path/to/destination_directory/
Both the source and target directories are local (in some file system accessible directly from stampede2). Either full or relative path syntax can be used for both. The -avW options above stand for:
- -a means "archive mode", which implies the following options (and a few others)
- -p – preserve file permissions
- -t – preserve file times
- -l – copy symbolic links as links
- -r – recursively copy sub-directories
- -v means verbose
- -W means transfer Whole file only
- Normally the rsync algorithm compares the contents of files that need to be copied and only transfers the different parts.
- For large files and binary files, figuring out what has changed (diff-ing) can take more time than just copying the whole file.
- The -W option disables file content comparisons (skips diff-ing).
Since these are all single-character options, they can be combined after one option prefix dash ( - ). You could also use options -ptlrvW, separately, instead of using -a for "archive mode".
Tip | ||
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The trailing slash ( / ) on the source and destination directories are very important for rsync (and for other Linux copy commands also)! rsync will create the last directory level for you, but earlier levels must already exist. |
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mkdir -p $SCRATCH/data
cds
rsync -avW $CORENGS/custom_tracks/ data/custom_tracks/ |
Exercise: What files were copied over?
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ls $SCRATCH/data/custom_tracks |
Now repeat the rsync and see the difference.
Use the Up arrow to retrieve the previous command from your bash command history.
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rsync -avW /work/projects/BioITeam/projects/courses/Core_NGS_Tools/custom_tracks/ data/custom_tracks/ |
Tip |
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The bash shell has several convenient line editing features:
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Copy from a remote computer - scp or rsync
Provided that the remote computer is running Linux and you have ssh access to it, you can use various Linux commands to copy data over a secure connection.
The good news is that once you have learned cp and local rsync, remote secure copy (scp) and remote rsync are very similar!
scp
The scp command copies one or more files from a source to a destination, where either source or destination, or both, can be a remote path.
Remote paths are similar to local paths, but have user and host information first:
user_name@full.host.name:/full/path/to/directory/or/file
– or –
user_name@full.host.name:~/path/relative/to/home/directory
Copy a single file to your $SCRATCH/data/test1 directory from the server named dragonfly.icmb.utexas.edu, using the user account corengstools. When prompted for a password, use the one we have written to the Zoom chat (or copy/paste the password from this file: $CORENGS/tacc/dragonfly_access.txt)
Code Block | ||
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cat $CORENGS/tacc/dragonfly_access.txt
cds
mkdir -p data/test2
scp corengstools@dragonfly.icmb.utexas.edu:~/custom_tracks/progeria_ctcf.vcf.gz ./data/test2/
ls ./data/test2 |
Notes:
- The 1st time you access a new host the SSH security prompt will appear
- You will be prompted for your remote host password
- The -r recursive argument works for scp also, just like for cp
remote rsync
rsync can be run just like before, but using the remote-host syntax. Here we use two tricks:
- The tilde ( ~ ) at the start of the path means "relative to my home directory"
- We use the tilde ( ~ ) in the destination to traverse the scratch symbolic link in your home directory.
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rsync -avW corengstools@dragonfly |
...
- Normally the rsync algorithm compares the contents of files that need to be copied and only transfers the different parts.
- For large files and binary files, figuring out what has changed (diff-ing) can take more time than just copying the whole file.
- The -W option disables file content comparisons (skips diff-ing).
Since these are all single-character options, they can be combined after one option prefix dash ( - ). You could also use options -ptlrvW, separately, instead of using -a for "archive mode".
Tip | ||
---|---|---|
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The trailing slash ( / ) on the source and destination directories are very important for rsync (and for other Linux copy commands also)! rsync will create the last directory level for you, but earlier levels must already exist. |
Code Block | ||||
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mkdir -p $SCRATCH/data
cds
rsync -avWP $CORENGS/custom_tracks/ data/custom_tracks/ |
Exercise: What files were copied over?
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ls $SCRATCH/data/custom_tracks |
Now repeat the rsync and see the difference.
Use the Up arrow to retrieve the previous command from your bash command history.
Code Block | ||
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rsync -avWP /work/projects/BioITeam/projects/courses/Core_NGS_Tools/custom_tracks/ data/custom_tracks/ |
Tip |
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The bash shell has several convenient line editing features:
|
Copy from a remote computer - scp or rsync
Provided that the remote computer is running Linux and you have ssh access to it, you can use various Linux commands to copy data over a secure connection.
The good news is that once you have learned cp and local rsync, remote secure copy (scp) and remote rsync are very similar!
scp
The scp command copies one or more files from a source to a destination, where either source or destination, or both, can be a remote path.
Remote paths are similar to local paths, but have user and host information first:
user_name@full.host.name:/full/path/to/directory/or/file
– or –
user_name@full.host.name:~/path/relative/to/home/directory
Copy a single file to your $SCRATCH/data/test1 directory from the server named gapdh.icmb.utexas.edu, using the user account corengstools. When prompted for a password, use the one we have written on the board (or copy/paste the password from this file: $CORENGS/tacc/gapdh_access.txt)
Code Block | ||
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cds cat $CORENGS/tacc/gapdh_access.txt scp corengstools@gapdh.icmb.utexas.edu:~/custom_tracks/progeria_ctcf.vcf.gz . ~/scratch/data/test1/ ls ./data/test1 |
Notes:
- The 1st time you access a new host the SSH security prompt will appear
- You will be prompted for your remote host password
- The -r recursive argument works for scp also, just like for cp
remote rsync
rsync can be run just like before, but using the remote-host syntax. Here we use two tricks:
- The tilde ( ~ ) at the start of the path means "relative to my home directory"
- We traverse through the BioITeam symbolic link created in your home directory earlier.
- We use the same tilde ( ~ ) in the destination to traverse the scratch symbolic link in your home directory.
Don't forget to change userid below.
Code Block | ||||
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rsync -ptlrvP corengstools@gapdh.icmb.utexas.edu:~/custom_tracks/ ~/scratch/data/custom_tracks/ |
Exercise: Was anything copied?
Expand | ||
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| ||
No, because all the source files were already present in the destination directory (you copied the same files earlier) with the same timestamps and file checksums. So rsync had nothing to do! |
Scavenger hunt exercise
Here's a fun scavenger hunt for more practice. Issue the following commands to get practice what you've learned so far:
Expand | ||
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Hit Tab Tab as much as possible to save typing! |
...
custom_tracks/ |
Exercise: Was anything copied?
Expand | ||
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No, because all the source files were already present in the destination directory (you copied the same files earlier) with the same timestamps. So rsync had nothing to do! |
Scavenger hunt exercise
Here's a fun scavenger hunt for more practice. Issue the following commands to get practice what you've learned so far:
Expand | ||
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Hit Tab Tab as much as possible to save typing! |
To get started:
Code Block | ||
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cd
cp -r /work2/projects/BioITeam/projects/courses/Core_NGS_Tools/linuxpractice/what what
# or using the $CORENGS environment variable
cp -r $CORENGS/linuxpractice/what what
cd what
cat readme |
Where are you when you're all done?
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step by step answers
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From inside your ~/what directory:
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From inside your ~/what/starts directory:
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Where are you when you're all done?
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step by step answers
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From inside your ~/what/starts/here directory:
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From inside your ~/what/starts directory:
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From inside your ~/what/starts/here directory:
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From inside your ~/what/starts/here/changes directory:
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...