Using Silo

Keep reading to learn how to access Silo and use the Windows servers in the Silo environment. Or you can skip ahead for information on:

• Silo's file system and getting data in and out of Silo 
• Linux servers in Silo 

Getting Access

If you are interested in using Silo, please contact the  SSCC Help Desk. L&S researchers should set up a consultation with the Data and Information Services Center for assistance with getting approval to work with sensitive data. SMPH researchers should set up a consultation with the Clinical and Health Informatics Institute. Depending on the nature of your data you may need to get approval from your IRB, the UW-Madison Office of Cybersecurity, or other relevant authorities. Using Silo will expedite that process because it has already had a formal risk assessment by the Office of Cybersecurity and was found to be low risk, and many of the relevant authorities are already familiar with it.  You can see what software is available in Silo in the SSCC's software database plus the Biomedical Research Software on Silo page.

Connecting to Silo requires multifactor authentication using Duo, the same system used for your UW-Madison NetID. Most people use the Duo app on their smartphone, but you can also use a separate hardware token. When you contact the Help Desk about using Silo please mention which method you prefer. Instructions for obtaining and using a hardware token can be found here. Consider turning on Duo Restore so you can easily continue using Duo after upgrading your phone.

Installing the Citrix Workspace App

To use Silo you'll need to have the Citrix Workspace App installed on your computer. Just click on the appropriate link below and then run the installer after it finishes downloading. If you've already installed the Citrix Workspace App on your computer in order to use Winstat you do not need to install it again.

• Citrix Workspace for Windows (Windows 10)
• Citrix Workspace for Windows from the Microsoft Store
• Citrix Workspace for Mac (macOS 10.15)
• Citrix Workspace for Linux

See Using Winstat  for more information about using the Citrix Workspace App.

Logging In

To log in to Silo, you will need go to the website silo.ssc.wisc.edu. If you're asked to give permission for programs to run, do so.

At the login screen, first give your SSCC username and password as usual. If it is your first time logging into Silo, you'll be prompted to follow the instructions on the screen to set up Duo on your smartphone. You'll be able to use the same Duo app for both Silo and your NetID.

The Silo File System

Silo has an isolated file system that is separate from the SSCC's primary file system, but they have similar structures. All files are available using either Windows or Linux. The key locations are:

Directories

	Linux Name	Windows Name
Home Directory (Private Space)	~	Z:  Drive
Project Directories (Shared Space)	/project	V:  Drive
SMPH Project Directories (Shared Space)	/smph	S:  Drive

Home directories are primarily meant for configuration files, installed packages, and other small files. They have a quota of 40GB. Research data should be stored in Project directories, which have no quotas and are shared with the other members of your research group. SMPH researchers will be given project space on the S: drive, which is SMPH's space in DoIT's RestrictedDrive service.

Moving Data To and From Silo

You can move data into or out of Silo using Globus, a tool for securely transferring research data. See Using Globus to Move Data In and Out of Silo for more information.

To easily move results out of Silo, we have created a folder called  silosync in the Z: drive of each Silo user. Every five minutes, an automated script copies anything placed in this folder to a corresponding folder in your Z: drive on the SSCC's primary file system. One easy way to access the SSCC's primary file system is to log into Winstat, which you'll see when you log into Silo. Winstat is very similar to WinSilo but, not being a high-security server, it can communicate with the local hard drive of your computer. After logging into Winstat, you'll see a drive called Local Disk (C: on {your computer}). You can drag files from the Z: drive to this drive to move files from SSCC's file system to your computer. You're also welcome to access the SSCC's primary file system by mapping a drive to it (Windows / macOS) or using FTP.

Using WinSilo

Once you've logged in, WinSilo behaves just like a regular Windows server, with a few important exceptions:

• Silo cannot access the Internet. This can affect programs in unexpected ways: for example, Stata's findit command takes much longer to run than usual and then only gives partial results, because it tries to reach Stata's web server and does not display any results until that attempt times out. Fortunately the results it does give are the ones you're most likely to need.
• You can install R packages from CRAN and Bioconductor, Stata packages from SSC, and Python packages from PyPI. If you need to install packages from other sources contact the Help Desk.
• You cannot copy and paste between Silo and your own computer.
• Silo cannot access disk space on your computer.
• You cannot print from Silo.

Silo Downtime

All of the SSCC’s servers except for Slurm and SlurmSilo are taken offline, patched, and rebooted from 6:00AM-8:00AM on the Wednesday after the third Tuesday of the month (the week after Microsoft’s “Patch Tuesday”).

If you don't anticipate using Silo's Linux servers, you can stop reading at this point. Welcome to Silo!

Silo Linux Servers

Silo has three kinds of Linux servers. To use them, first sign into silo.ssc.wisc.edu. You can then either log into LinSilo directly or log into WinSilo and connect to the Linux servers from there.

LinSilo is a cluster of two servers ( linsilo001, linsilo002) with 44 cores and you can use up to 250GB of memory. When you log into LinSilo, you'll be automatically directed to the least busy server.

LinSiloBig is a single server (linsilobig001) with 80 cores and you can use up to 500GB of memory. 

Jobs that cannot run without the additional memory LinSiloBig provides should have first priority on LinSiloBig. Jobs that can take full advantage of the additional cores it provides are second priority. Please do not use LinSiloBig for jobs that could run just as well on LinSilo or SlurmSilo.

SlurmSilo is a cluster of five servers identical to LinSilo and one identical to LinSiloBig. They run jobs submitted to Slurm from LinSilo or LinSiloBig. Slurm allows you to submit jobs that will run on any of the servers in the cluster, reserving the cores and memory they need (up to 80 cores and 750GB of memory).

The Linux servers in the Silo environment were funded by SMPH. Other researchers are welcome to use them, but SMPH researchers have priority.

To learn how to use the Linux servers in Silo, please see the Guide to Research Computing at the SSCC.

Logging in to Silo Using a Hardware Token

If you would like to use a token to log into Silo and have one already, please contact the Help Desk and include the serial number printed on the back of your token in your email. The token must be black and white colored, with the words "OTP c100" printed on the front - we cannot use the blue and green tokens that say "Duo" on the front. If you do not have a token, please let us know and we will issue you one.

Log in by going to silo.ssc.wisc.edu  and giving your SSCC username and password as usual. Then click Enter a Passcode and press the button on your token. Enter the 6-digit number from your token and click Log In  .

If later you wish to add a smartphone app to your Silo account so you can authenticate with either the app or a token, click Add a new device under the SSCC logo and follow the onscreen instructions.

If you have any questions about using Silo, feel free to contact the Help Desk.