OpenMPI, Intel Compilers and RedHat 5: cannot find -lnuma

I found an interesting quirk when trying to build an OpenMPI application on a visualization node with a “stock” version of Red Hat Enterprise Linux 5.8.  I used mpicc to compile the application and got the following error:

$ mpicc hello_world_mpi.c -o hello_world
/usr/bin/ld: cannot find -lnuma

This was rather surprising, since this node mounts a directory via NFS that contains OpenMPI and Intel Composer 2013, and these applications are known to work on other nodes. To find the source of the problem, I used the showme option to see the command that is actually run by mpicc:

$ mpicc hello_world_mpi.c -o hello_world --showme
icc hello_world_mpi.c -o hello_world -I/apps/openmpi/openmpi-1.6.2-intel-composer-2013/include -pthread -L/apps/openmpi/openmpi-1.6.2-intel-composer-2013/lib -lmpi -ldl -lm -lnuma -Wl,--export-dynamic -lrt -lnsl -lutil

The output was identical to the output on the other nodes…so why was this node failing to find libnuma? It turned out that OpenMPI looks for a library called libnuma.so, while RHEL only includes a library called libnuma.so.1, and it is missing a symbolic link that points libnuma.so to libnuma.so.1. The solution is to create the symbolic link:

$ ln -s /usr/lib64/libnuma.so.1 /usr/lib64/libnuma.so
$ ls -l /usr/lib64/libnuma*
lrwxrwxrwx 1 root root    23 Feb 20 17:37 /usr/lib64/libnuma.so -> /usr/lib64/libnuma.so.1
-rwxr-xr-x 1 root root 22032 May 17  2011 /usr/lib64/libnuma.so.1
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## Comments

### Comment #1 by Dave X

[Dave X](mailto:<drf@vims.edu>) - Apr 5, 2015

The libnuma-devel rpm includes this symlink and some of the include files.

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#### Comment #2 by mdiehn

[mdiehn](mailto:<mike@diehn.net>) - Nov 4, 2016

Thanks, bub. Symlinked it an away we go!

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