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--- howto:start [2026/02/20 09:42]
ccrosby
+++ howto:start [2026/09/09 09:13] (current)
ccrosby Replaced the "logging in for the first time" video with the Heath Robinson method dictated in 2026.
@@ Line 3: / Line 3: @@
 ===== Video tutorials for newcomers =====
 If you are a new user to the CHPC, please watch these videos:
-  * [[https://youtu.be/fCM8ZaFn4rs|Setting up a cluster password and logging in for the first time]]
+  * [[https://youtu.be/Fq6xT-KjlQ0|The revised login procedure]]
   * [[https://youtu.be/CIEVMlrKXF4|The CHPC's service nodes and using the module system]]
   * [[https://youtu.be/mQjh8J_aMYU|Test running in an interactive PBS session]]
@@ Line 10: / Line 10: @@
 ===== Tips and Tricks =====
 [[howto:TipsAndTricks|Tips & tricks for common tasks.]] :!: ** Please read this.  The information is based on hard won experience. ** :!:
+===== If you need more memory =====
+As of May 2025, 41 compute nodes have had more memory added, cannibalizing memory modules from nodes that have failed permanently.  These 24-core nodes now have 256 GB of RAM each.  You can access these nodes by including the directive ''mem=250gb'' in your resource request line.  These nodes work with the usual queues such as smp, normal or large.
+<code>
+#PBS -l select=1:ncpus=24:mpiprocs=24:mem=250gb
+</code>
+Only use these nodes if you need more than 128 GB of RAM, but less than the 1TB available on the "fat nodes".
 ===== Using the Intel compilers =====
@@ Line 56: / Line 67: @@
 export MPIF77=mpiifx
 export MPIF90=mpiifx
+export I_MPI_HYDRA_BOOTSTRAP=ssh
 </code>
-It is not necessary to use a machinefile for multi-node MPI runs.  However, the default bootstrap method using pbsdsh does not work.  It is necessary to set the bootstrap method to ssh.  This is a typical command mpi run command:
+It is not necessary to use a machinefile for multi-node MPI runs.  However, the default bootstrap method using pbsdsh does not work, hence the need to set ''I_MPI_HYDRA_BOOTSTRAP''.  This is a typical command mpi run command:
 <code>
-mpirun -np 96 -bootstrap ssh myMPIprogram.exe
+mpirun -np 96 myMPIprogram.exe
 </code>
-===== If you need more memory =====
-As of May 2025, 41 compute nodes have had more memory added, cannibalizing memory modules from nodes that have failed permanently.  These 24-core nodes now have 256 GB of RAM each.  You can access these nodes by including the directive ''mem=250gb'' in your resource request line.  These nodes work with the usual queues such as smp, normal or large.
-<code>
-#PBS -l select=1:ncpus=24:mpiprocs=24:mem=250gb
-</code>
-Only use these nodes if you need more than 128 GB of RAM, but less than the 1TB available on the "fat nodes".
 ===== Transferring data to DIRISA =====
 Long-term data storage through [[howto:Dirisa|DIRISA.]]

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