Squiggles research computer server: Difference between revisions

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=== Introduction ===
=== Introduction ===
"Squiggles" is a dedicated research computer server for the analysis and storage of MEG, Neurophysiology, and Epilepsy data. Users can connect to it using either the FastX connection (recommended) or the older VNC method. This guide provides detailed steps for both methods.
"Squiggles" is a dedicated research computer server tailored for the analysis and storage of MEG, Neurophysiology, and Epilepsy data. This guide outlines how to connect using either the recommended FastX connection or the traditional VNC method.


=== Access Requirements ===
=== Access Requirements ===
==== RCC account ====
==== RCC Account ====
To access "Squiggles", users must first have an RCC (Research Computer Server) account.
* Request an account at [[https://infoscope.mcw.edu/RCC/Research-Computing-Center.html MCW-Infoscope's Research Computing Center]].
* If asked, select "others" and then "squiggles" to specify the desired server.
* Follow the provided steps to initiate a new session and gain remote access to Squiggles.


=== How to Access Squiggles ===
* An RCC (Research Computer Server) account is necessary to access "Squiggles".
* Register for an account at [https://docs.rcc.mcw.edu/user-guide/accounts/ MCW-Infoscope's Research Computing Center].
* If prompted, select "others" and then "squiggles" to specify the server you wish to access.
* Account approval generally takes 1-3 days. For any issues, contact Help-RCC at <help-rcc@mcw.edu>.


==== SSH Tunneling Method (for Mac/Linux/Windows) ====
=== Login to Squiggles ===
Use the following command in a bash shell, terminal or Windows power shell to establish an SSH tunnel for the VNC Viewer:
'''Choosing a User Port:''' Each user is allocated a specific port number. New users should pick a port number (##) not already in use:
<code> ssh -N -L 59**:localhost:59** squiggles.rcc.mcw.edu</code>
 
==== VNC Method (for Windows) ====
 
'''Configuration''':
* Download [https://www.chiark.greenend.org.uk/~sgtatham/putty/ Putty].
 
[[File:Putty config1.PNG]]
[[File:Putty config2 tunnel.PNG]]
 
=====VNC User Ports:=====
Users must log in using their designated port numbers. Below is the list of users and their respective ports:


{| class="wikitable"
{| class="wikitable"
Line 32: Line 19:
|-
|-
|Jeff Stout
|Jeff Stout
|5910,5911
|5910, 5911
|-
|-
|Joe Heffernan
|Joe Heffernan
|5912
|5912
|-
|Manoj Raghavan
|5913, 5998, 5999
|-
|-
|Candida Ustine
|Candida Ustine
|5914
|5914
|-
|Manoj Raghavan
|5913
|-
|-
|Chad Carlson
|Chad Carlson
Line 88: Line 75:
|5929
|5929
|-
|-
|Vahab Youssofzadeh
|Setayesh Abiazi Shalmani
|5930
|-
|Vahab Youssof Zadeh
|5931
|5931
|-
|-
Line 94: Line 84:
|5935
|5935
|-
|-
|Cameron J Stewart  
|Rupesh Chikara
|5944
|-
|Cameron J Stewart
|5992
|5992
|}
|}


=====Creating a VNC Session=====
===== SSH Tunneling =====
* VNC sessions auto-start at bootup using the above-listed port numbers.
* '''PowerShell Method (Mac/Linux/Windows):''' In a bash shell, terminal, or Windows PowerShell, execute the following to set up an SSH tunnel for the VNC Viewer:
* If you encounter any issues, initiate a session manually using: <code>vncserver :## -geometry 1900x1200</code>. Replace <code>##</code> with your specific port number.
<code>ssh -L 59##:localhost:59## USER@squiggles.rcc.mcw.edu</code>
where USER is your rcc user account and ## is the selected port number
 
* '''PuTTY (Windows):'''
[https://www.chiark.greenend.org.uk/~sgtatham/putty/ Download PuTTY] for SSH tunneling and refer to the images below for configuration:
 
PuTTY is an open-source software used for SSH Tunneling (or SSH Port Forwarding).
 
[[File:Putty config1.PNG]]
[[File:Putty config2 tunnel.PNG]]


=====Connecting to a VNC Session=====
=== Starting a Session and Connecting to Squiggles ===
'''RealVNC method''':
Ensure you've established an SSH tunnel before proceeding with either the VNC or FastX methods.
* To access, use the [[https://www.realvnc.com/en/connect/download/viewer/ RealVNC viewer]].
* In the server address bar, input <code>localhost:##</code>, where <code>##</code> corresponds to the last two digits of your port number.
* Authenticate using both your VNC and RCC credentials.


[[image:vncviewer.png]]
==== VNC Method (preferred) ====
* '''Creating & Accessing a VNC Session''':
** VNC sessions initialize automatically upon boot-up.
** If issues occur, manually initiate a session using: <code>vncserver :## -geometry 1900x1200</code>, where <code>##</code> is your specific port number.
** Access the session using the [[https://www.realvnc.com/en/connect/download/viewer/ RealVNC viewer]].
** Input <code>localhost:##</code> in the server address bar, where <code>##</code> corresponds to the last two digits of your port.


'''FastX Method:'''
[[image:vncviewer.png]]
* FastX may offer a more user-friendly connection than VNC and address issues related to a large number of simultaneous VNC users.
 
* Download the [https://www.starnet.com/fastx/current-client FastX client] and follow these steps:
<!-- ==== FastX Method (alternative) ====
** Open FastX.
FastX offers a potentially smoother experience compared to VNC, especially with multiple concurrent users.
** Click the '+' to initiate a new connection.
* Download the [https://www.starnet.com/fastx/current-client FastX client] and:
** Provide the Connection Name, host (squiggles.rcc.mcw.edu), and user (your RCC username).
** Start FastX.
** To enter a session, click the '+' and use /etc/X11/xinit/xinitrc as the command.
** Click '+' to establish a new connection.
** Provide the Connection Name, host (squiggles.rcc.mcw.edu), and your RCC username.
** Start a session by clicking '+' and using the command <code>/etc/X11/xinit/xinitrc</code>.
 
[[File: FastX_config.png]] -->


[[File: FastX_config.png]]


=== Troubleshooting ===
=== Troubleshooting ===
====Common issues & Solutions====
;'''Identifying Active Users'''
* '''VNC Black Screen:''' If VNC shows a black screen after login, ensure Anaconda Python is deactivated before creating the VNC session. Use the <code>conda deactivate</code> command in the terminal.
:To compile a list of users with active VNC sessions, which aids in monitoring current access to the VNC service, execute:
* '''FastX as an Alternative:''' If you experience persistent issues with VNC, consider using the FastX method described above.
:<code>ls -l /tmp/.X11-unix</code>
:This information can be used to oversee session activity and ensure that resources are allocated efficiently.


'''Additional VNC Session Management''':
;'''Terminating a VNC Session'''
* '''Killing a VNC session''': In the terminal, use <code>vncserver -kill :xx/</code>. If required to kill manually, execute:
:For situations where session termination is necessary, you can directly close a VNC session through the terminal or opt for manual termination if the direct method is insufficient. To directly terminate a session, use:
<pre>
:<code>vncserver -kill :##</code>
rm -f /tmp/.Xxx-lock
:Replace <code>:##</code> with your session number.
rm -f /tmp/.X11-unix/Xxx
</pre>
* '''List of Active Users''': Use the command <code>ls -l /tmp/.X11-unix</code> in the terminal.


====Creating a VNC session====
;'''Manual Termination of the VNC'''
VNC sessions will be created at bootup using the port numbers above
:For manual termination, proceed to remove the session files with:
If the VNC session fails or is not working:
:<code>rm -f /tmp/.X##-lock</code>
<code>vncserver :## -geometry 1900x1200</code> (This will open a vnc session on port 59## with a resolution of 1900x1200)  The ## must match your port number for this to work.
:<code>rm -f /tmp/.X11-unix/X##</code>
:Ensure to replace <code>X##</code> with the correct session identifier. This allows for removing stuck or unresponsive sessions that cannot be closed normally.


====Connecting to a VNC session====
;'''Alternative Solution: when Manual Termination of the VNC does not work'''
Use realvnc viewer to log into your VNC session. 
:Use the following command, replacing <code>&lt;username&gt;</code> with the actual username:
=====VNC viewer download=====
:<code>ps -ef | grep &lt;username&gt;</code>
Realvnc has been tested to work - https://www.realvnc.com/en/connect/download/viewer/
:This will list all processes related to the specified user. You can then terminate unwanted sessions by killing the process IDs:
=====Log in using RealVNC=====
:<code>kill -9 &lt;PID&gt;</code>
Open vncviewer
:Where <code>&lt;PID&gt;</code> is the process ID obtained from the previous command's output.
In the top bar that accepts a VNC Server address <br />
type localhost:##  (where ## are the last two digits of your port number 59##)
[[image:vncviewer.png]]
Log into the VNC session using your VNC password <br />
Once the VNC window is open, log into the server using your RCC password


=====Killing a VNC session=====
:Optional: To check the environment variables active during a VNC session, which can help in troubleshooting further issues, view the VNC environment log:
From the terminal try, <code> vncserver -kill :xx/ </code> <br />
:<code>cat ~/vnc.log</code>
For a manual kill (if asked) try, <br />
<pre>
rm -f /tmp/.Xxx-lock
rm -f /tmp/.X11-unix/Xxx
</pre>


=====List of users=====
;'''VNC connection‑closed / black‑screen issue'''
From the terminal try, <br />
:Anaconda’s base environment can interfere with VNC and close the session. 
<code>ls -l /tmp/.X11-unix</code>
:Deactivate it after login:
:<code>conda deactivate</code>


=====Common issues & Solutions=====
;'''Disable Conda auto‑activation (so you don’t have to run <code>conda deactivate</code> each time)'''
FastX is an alternative to VNC viewer
:If you seldom need Conda inside VNC, turn off automatic activation:
 
:* Run <code>conda config --set auto_activate_base false</code> (this updates <code>~/.condarc</code>), **or** 
* Before a VNC session is created, anaconda python must be deactivated. Enter <code>conda deactivate</code> into the terminal. If the user does not deactivate anaconda python, VNC will start, but a black screen is shown after logging in.
:* Edit <code>~/.bashrc</code> and comment out / delete the line that calls <code>conda activate base</code>.
:After logging out and back in, Conda will stay inactive by default; activate it later with <code>conda activate &lt;env&gt;</code> only when needed.
</pre>

Latest revision as of 15:23, 21 April 2025

Introduction

"Squiggles" is a dedicated research computer server tailored for the analysis and storage of MEG, Neurophysiology, and Epilepsy data. This guide outlines how to connect using either the recommended FastX connection or the traditional VNC method.

Access Requirements

RCC Account

  • An RCC (Research Computer Server) account is necessary to access "Squiggles".
  • Register for an account at MCW-Infoscope's Research Computing Center.
  • If prompted, select "others" and then "squiggles" to specify the server you wish to access.
  • Account approval generally takes 1-3 days. For any issues, contact Help-RCC at <help-rcc@mcw.edu>.

Login to Squiggles

Choosing a User Port: Each user is allocated a specific port number. New users should pick a port number (##) not already in use:

User Port
Jeff Stout 5910, 5911
Joe Heffernan 5912
Manoj Raghavan 5913, 5998, 5999
Candida Ustine 5914
Chad Carlson 5915
Chris Anderson 5916
Serena Thompson 5917
Patrick Bauer 5918
Jeff Binder 5919
Leo Fernandino 5920
Lisa Conant 5921
Aqil Izadysadr 5922
Nick Guzowski 5923
Zack Harper 5924
Bill Gross 5925
Michelle Kassel 5926
Greg McQuestion 5927
Monica Keith 5928
Priyanka Shah 5929
Setayesh Abiazi Shalmani 5930
Vahab Youssof Zadeh 5931
Songhee Kim 5935
Rupesh Chikara 5944
Cameron J Stewart 5992
SSH Tunneling
  • PowerShell Method (Mac/Linux/Windows): In a bash shell, terminal, or Windows PowerShell, execute the following to set up an SSH tunnel for the VNC Viewer:

ssh -L 59##:localhost:59## USER@squiggles.rcc.mcw.edu where USER is your rcc user account and ## is the selected port number

  • PuTTY (Windows):

Download PuTTY for SSH tunneling and refer to the images below for configuration:

PuTTY is an open-source software used for SSH Tunneling (or SSH Port Forwarding).

Putty config1.PNG Putty config2 tunnel.PNG

Starting a Session and Connecting to Squiggles

Ensure you've established an SSH tunnel before proceeding with either the VNC or FastX methods.

VNC Method (preferred)

  • Creating & Accessing a VNC Session:
    • VNC sessions initialize automatically upon boot-up.
    • If issues occur, manually initiate a session using: vncserver :## -geometry 1900x1200, where ## is your specific port number.
    • Access the session using the [RealVNC viewer].
    • Input localhost:## in the server address bar, where ## corresponds to the last two digits of your port.

Vncviewer.png


Troubleshooting

Identifying Active Users
To compile a list of users with active VNC sessions, which aids in monitoring current access to the VNC service, execute:
ls -l /tmp/.X11-unix
This information can be used to oversee session activity and ensure that resources are allocated efficiently.
Terminating a VNC Session
For situations where session termination is necessary, you can directly close a VNC session through the terminal or opt for manual termination if the direct method is insufficient. To directly terminate a session, use:
vncserver -kill :##
Replace :## with your session number.
Manual Termination of the VNC
For manual termination, proceed to remove the session files with:
rm -f /tmp/.X##-lock
rm -f /tmp/.X11-unix/X##
Ensure to replace X## with the correct session identifier. This allows for removing stuck or unresponsive sessions that cannot be closed normally.
Alternative Solution: when Manual Termination of the VNC does not work
Use the following command, replacing <username> with the actual username:
ps -ef | grep <username>
This will list all processes related to the specified user. You can then terminate unwanted sessions by killing the process IDs:
kill -9 <PID>
Where <PID> is the process ID obtained from the previous command's output.
Optional: To check the environment variables active during a VNC session, which can help in troubleshooting further issues, view the VNC environment log:
cat ~/vnc.log
VNC connection‑closed / black‑screen issue
Anaconda’s base environment can interfere with VNC and close the session.
Deactivate it after login:
conda deactivate
Disable Conda auto‑activation (so you don’t have to run conda deactivate each time)
If you seldom need Conda inside VNC, turn off automatic activation:
  •  Run conda config --set auto_activate_base false (this updates ~/.condarc), **or**
  •  Edit ~/.bashrc and comment out / delete the line that calls conda activate base.
After logging out and back in, Conda will stay inactive by default; activate it later with conda activate <env> only when needed.
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