Add FAQ for RStudio timeout issue.

Author: Guangzhen-Jin

docs/assets/images/userguides/rstudio_timeout1.png

@@ -0,0 +1,57 @@
+**Problem**
+
+RStudio Server times out after approximately 60 minutes of inactivity. Upon re-entering the session, there will be a "RStudio Server Login Required" window popping up as below.
+
+<td style="text-align: center;">
+    <img src="/assets/images/userguides/rstudio_timeout1.png" alt="Rstudio login required">
+</td>
+
+When trying to log in from the login window below, your login credentials **WILL NOT** work.
+
+<td style="text-align: center;">
+    <img src="/assets/images/userguides/rstudio_timeout2.png" alt="Rstudio login window">
+</td>
+
+**Solution**
+
+This issue is related to the RStudio Server configuration that sessions will automatically log out if inactive for over **60 minutes**. The solution would be either to keep active every 60 minutes or use the user name and password (session specific password) described as follows to re-login:
+
+1. Navigate to the current RStudio session in Open OnDemand.
+
+    <td style="text-align: center;">
+        <img src="/assets/images/userguides/rstudio_timeout3.png" alt="Rstudio session ID" width="90%">
+    </td>
+
+2. Click on the session ID to open the session folder and locate the `connection.yml` file within the session folder.
+
+    <td style="text-align: center;">
+        <img src="/assets/images/userguides/rstudio_timeout4.png" alt="Rstudio session folder" width="90%">
+    </td>
+
+3. Open it to find the session-specific password. 
+
+    ```
+    csrf_token: ***************
+    host: a007.cluster.rcac.purdue.edu
+    port: 5329
+    password: ***************
+    ```
+
+4. Then, use your Purdue account username in the "Username" field and the password retrieved from the `connection.yml` file to re-login.
+
+P.S. If you could not open the page after re-login (see below) and saw the web url ended with `/appUri`, delete `/appUri` and retry with the remaining url. 
+
+<td style="text-align: center;">
+    <img src="/assets/images/userguides/rstudio_timeout5.png" alt="Rstudio URL mismatch">
+</td>
+
+
+
+
+
+
+
+
+
+
+

docs/assets/images/userguides/rstudio_timeout2.png

@@ -224,3 +224,8 @@ You can search all modules using `$ module spider`. Some modules require you to
 ### Jupyter:  database is locked / can not load notebook format
 
 --8<-- "docs/snippets/jupyter_lock.md"
+
+### RStudio Server Timeout
+
+--8<-- "docs/snippets/rstudio_timeout.md"
+

docs/assets/images/userguides/rstudio_timeout3.png

@@ -438,6 +438,10 @@ $ export JULIA_DEPOT_PATH=$HOME/.julia
 $ julia -e 'using Pkg; Pkg.add("PackageName")'
 ```
 
+### RStudio Server Timeout
+
+--8<-- "docs/snippets/rstudio_timeout.md"
+
 ## About Research Computing
 
 ### Can I get a private server from RCAC?

docs/assets/images/userguides/rstudio_timeout4.png

@@ -79,4 +79,8 @@ Users who have access to **Gautschi** can use **ThinLinc** to launch an interac
 
 ### Jupyter:  database is locked / can not load notebook format
 
---8<-- "docs/snippets/jupyter_lock.md"
+--8<-- "docs/snippets/jupyter_lock.md"
+
+### RStudio Server Timeout
+
+--8<-- "docs/snippets/rstudio_timeout.md"

docs/assets/images/userguides/rstudio_timeout5.png

@@ -88,5 +88,8 @@ gilbreth-a003:~$ lstopo-no-graphics --physical --whole-io
 
 --8<-- "docs/snippets/jupyter_lock.md"
 
+### RStudio Server Timeout
+
+--8<-- "docs/snippets/rstudio_timeout.md"
 
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