Running HNN with X11 Forwarding on Oscar

Installing the X11 client

Download the installer image (version 2.7.11 tested): https://www.xquartz.org/
Open the .dmg image and run XQuartz.pkg within the image, granting privileges when requested.
Start the XQuartz.app by searching for XQuartz in Spotlight (upper right search icon). An “X” icon will appear in the taskbar along with a terminal. We will not use this window because it is difficult to copy and paste into it, so you can close it by clicking on the red x in the upper left corner.
- Alternatively steps 2 and 3 can be run from the terminal app (enter your user password when prompted after the sudo command):
```
hdiutil attach ~/Downloads/XQuartz-2.7.11.dmg
sudo installer -pkg /Volumes/XQuartz-2.7.11/XQuartz.pkg -target /
hdiutil detach /Volumes/XQuartz-2.7.11
rm ~/Downloads/XQuartz-2.7.11.dmg
open /Applications/Utilities/XQuartz.app
```

Download the installer from https://sourceforge.net/projects/vcxsrv/files/latest/download (click here for the direct download link for version 64.1.20.1.4)
Run the installer, choosing any installation folder.
Start the XLaunch desktop app from the VcXsrv folder in the start menu.
Choose “Multiple windows” and Click ‘Next’.
Select “Start no client” and click ‘Next’.
Click “Save configuration” to create a shortcut with the settings we just chose. Click “Finish” and an “X” icon will appear in the lower-right dock signaling that VcXsrv has started.
A message from Windows firewall to allow connections may pop up. If it does, choose options allowing connections to the VcXsrv when connected to both public and private networks.

Start your X11 client and leave running in the background
Run the ssh command below from a terminal window. The -X is important to enable X11 forwarding for the GUI.
```
ssh -X YOUR_USERNAME@ssh.ccv.brown.edu
```
Log in using your CCV account password
Start an interactive job with the interact command. Choose the number of cores for your allocations. If you have an exploratory account, you are limited to 16 cores. You can also use a condo account to use larger allocations.
```
interact -n 16
```
- When the command above succeeds your command prompt will change from [USER@login00XX ~]$ to [USER@nodeXXXX ~]$
Run the following commands to pull the HNN container and start the HNN GUI. If are logging in again, skip to “Running HNN a second time” below.
```
singularity pull docker://jonescompneurolab/hnn
singularity run hnn.simg
```
You can now proceed to the tutorials at https://hnn.brown.edu/index.php/tutorials/ . Some things to note:
- The files within the container are visible are integrated within Oscar’s view of your director. For example, your user directory might be /users/myuser and the hnn_user within the container has a user directory /home/hnn_user. If you are loading sample files for the tutorials, look in /home/hnn_user/hnn_source_code. Your output from simulations will be stored in /users/myuser/hnn_out

Omit the singularity pull command from above. The large hnn.simg file was downloaded before and can be used directly this time.

For HNN software issues, please visit the HNN bulletin board and create a new post with your environment and any relevant error messages.