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--- quick:help [2021/08/12 16:24]
alopis [Some hints on resolving your difficulty]
+++ quick:help [2025/06/30 14:39] (current)
ccrosby [The Help Desk]
@@ Line 2: / Line 2: @@
 ===== The Help Desk =====
-If you need assistance, please go to [[http://users.chpc.ac.za/helpdesk|the support query page]].  However, before you do that, please ensure that you have crucial information available, and include it in your submission.  It is helpful to ask yourself the following question: "What information do I need to provide to the support agent in order for that person to fully understand my difficulty?"
+If you need assistance, please go to [[http://users.chpc.ac.za/helpdesk|the support query page]].  However, before you do that, please ensure that you have crucial information available, and include it in your submission.  It is helpful to ask yourself the following question: "What information do I need to provide to the support agent in order for that person to fully understand my difficulty?"  You can also send emails directly to [[helpdesk@chpc.ac.za]].  Using either method, **please** identify yourself with the same email address as the one used when you registered on the CHPC user portal.  This immediately links your query to your information on our user portal, which makes it easier and faster to provide assistance.
 ===== Please RTFM (Read The Fine Manual) =====
 Before submitting the support request, please take a moment to read whatever relevant documentation is available on [[http://wiki.chpc.ac.za|the CHPC Wiki]].  The Wiki is updated as things change and we become aware of existing difficulties, solutions and workarounds.  Please check back often.
+===== Asking for help with login problems =====
+CHPC users log into the cluster using the secure shell protocol, or ssh.  However, there are many different software clients that can be used for this purpose, such as command line ssh from Linux, Windows or macOS, or applications such as PuTTY, MobaXterm or WinSSH.  Not all of these provide helpful information when things go wrong.  The command line tools can typically be used with additional parameters to provide helpful information.  For example:
+<code>
+ssh -v jblogs@lengau.chpc.ac.za
+</code>
+will provide some additional information and
+<code>
+ssh -vv jblogs@lengau.chpc.ac.za
+</code>
+even more.  Simply saying "I cannot log in" does not enable us to help you.  It could be for one of many reasons, such as:
+  - Network problems at the user's end
+  - Network problems at the CHPC's end
+  - Blocked login due to too many failed attempts
+  - Forgotten or mis-typed password
+  - A problem with the CHPC's login and authentication system
+  - A problem with the user's ssh client software
+Here are some things that the user can try:
+  - Use a different client
+  - Get verbose output, as described above, to try and diagnose the problem
+  - Check network connectivity
+  - Check ssh login to a totally different site, if possible
+  - Try the alternative login node, such as ''scp.chpc.ac.za'', or the CHPC's data transfer node ''dtn.chpc.ac.za''
 ===== Some hints on resolving your difficulty =====
@@ Line 16: / Line 42: @@
   * Please put some effort into estimating and requesting a realistic Walltime.  If you ask for much more than you really need, the scheduler will have to wait longer in order to find a large enough gap.
   * Please try repeat a previous calculation which actually worked - please make sure to keep a backup of this previous calculation (please do not overwrite your old results).
+  * Please confirm you are submitting to the appropriate queue. Possible queues: http://wiki.chpc.ac.za/quick:start?s[]=smp#queues
+  * The error messages in your code's output and the standard error file are very helpful. The first instance of the error or warning is often the most significant one.
 ===== Information to include in your support query =====

wiki.chpc.ac.za

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