use-submit-node.shtml

---
layout: default
title: Using CHTC's HTC Submit Servers
---

<p><b>If you have not yet requested a CHTC account and met with a 
Research Computing Facilitator, please fill out <a href="{{'/form' | relative_url }}">
this form</a>.</b></p>

<p>Recently created CHTC accounts will use our submit server <i>submit2.chtc.wisc.edu</i>. 
Access to other submit servers is granted
 for specific purposes and will have been indicated to you by CHTC staff. 
<h2>Connecting to CHTC Submit Servers</h2>
When your CHTC account is active, you can connect to one of our submit servers
 with an SSH connection ("Putty" for Windows, putty.org; "Terminal" for Linux/Max).
 Note, however, that our submit servers only accept connections from campus
 networks. Off-campus connections have been disabled for security purposes. 
If you need to connect from off campus, you can first SSH to a computer in your department, and then SSH to our 
submit server. You may also be able to use a Virtual Private Network (VPN) to join the campus network when working off-campus. 
DoIT provides <a href="https://it.wisc.edu/services/wiscvpn/">information on using a VPN</a>.</p>

<p>For more detailed information on connecting to CHTC services, both logging in and 
transferring files, see our <a href="{{'/connecting' | relative_url }}">Connecting to CHTC guide</a>.</p>

<h2>Data Practices</h2>
<strong>We do not back up data on CHTC submission points</strong>, and users
 should treat CHTC compute systems as temporary storage locations for
 <i>active</i>, currently-queued computational work. Users should remove data from
 CHTC systems upon completion
 of a batch computational work and keep copies of all essential files in a non-CHTC
 location. CHTC staff reserve the right to delete data from any CHTC file systems at
 at any time, to preserve performance, and are not responsible for data loss for file
 system corruption, which are possible, especially in the absence of back-ups.
<h2>Submit Server User Policies</h2>
Because our submit servers are shared by many CHTC users, anyone with an
 account on CHTC's submit servers should follow the below policies, in order
 to keep the submit servers functional and usable by everyone:
<ul>
<li><strong>Do not share accounts</strong>. We are happy to make new a new account for any user. Sharing accounts
 is against campus policy and, therefore, CHTC policy. Accounts that we notice being shared will be immediately disabled
 and a meeting with the PI (faculty advisor) will be necessary to reinstate the account.
<li><strong>Do not run programs on the submit server.</strong> The submit server
 is kept plenty busy just managing HTCondor jobs. Computational work,
 like compiling code, should be submitted as HTCondor jobs. See our
 <a href="{{'/guides' | relative_url }}">online guides</a>
 for the best compiling practices. Small scripts and commands (to compress data,
 create directories, etc.) that run within a
 few minutes on the submit server are okay, but their use should be minimized when possible.
<li><strong>Jobs with long runtimes.</strong> There is a default run limit of 72 hours for each job 
queued in the HTC System, once it starts running. Jobs longer than this will be placed in 
HTCondor's "hold" state. If your jobs will be longer, please 
<a href="mailto:chtc@cs.wisc.edu">email us</a>, and we'll help you to determine the best solution.
<li><strong>Submitting many jobs from one submit file.</strong> HTCondor is designed 
to submit thousands of jobs from one submit file.  However, submitting too many 
jobs at once provides no extra benefit to the submitter and can make the queue 
work more slowly. If you are submitting <u>over 10,000 jobs per submit file</u> or have 
submitted over <u>50,000 jobs at once as a single user</u>, 
please <a href="mailto:chtc@cs.wisc.edu">email us</a> as we have strategies to submit 
that many jobs in a way that will ensure you have as many jobs running 
as possible without also compromising the queue.</li>
<li><strong>There is a 20 GB disk quota</strong> in your <code>/home</code>
 directory, by default. You can track your use of disk space, and your quota
 value, using our <a href="{{'/check-quota' | relative_url }}">Quota
 Guide</a>. If you need more space for concurrent work, please send an email
 to chtc@cs.wisc.edu.
<li><strong>Submitting jobs with "large" files:</strong> Please do not
 submit jobs that require single input files larger than 100 MB using
 HTCondor's normal file transfer mechanism ("transfer_input_files"),
 or that produce output files greater than a few GB. For such jobs
 with large files, please see our guide on
 <a href="{{'/file-availability' | relative_url }}">File Availability</a>
 Options, and contact us to make arrangements.
<li><strong>No scheduled jobs.</strong> Local execution and job
 submission should be manual, or use a DAG. Do not use cron to
 schedule jobs, and do not submit jobs with a script that uses "sleep"
 or otherwise doesn't complete while you are logged in. Contact us
 if you need job scheduling.
 </ul>