Purdue University

Can you remove me from the Bell mailing list?

Your subscription in the Bell mailing list is tied to your account on Bell. If you are no longer using your account on Bell, your account can be deleted from the My Accounts page. Hover over the resource you wish to remove yourself from and click the red 'X' button. Your account and mailing list subscription will be removed overnight. Be sure to make a copy of any data you wish to keep first.

How is Bell different than other Community Clusters?

Bell differs from the previous Community Clusters in several significant aspects:

• Bell home directories are entirely separate from other Community Clusters home directories. There is no automatic copying or synchronization between the two. At their discretion, users can copy parts or all of the Community Clusters home directory into Bell - instructions are provided.
• Users of hsi and htar commands may encounter Fortress keytab- and authentication-related error messages due to the dedicated nature of Bell home directories. A temporary workaround is provided while a permanent solution is being developed.
• Bell contains the latest generation of AMD EPYC processors, codenamed "Rome". These CPUs support AVX2 vector instructions set. When compiling your code, use of -march=znver2 flag (for latest GCC, Clang and AOCC compilers) or -march=core-avx2 (for Intel compilers and GCC prior to 9.3) is recommended.
• If your application heavily uses Intel MKL routines, setting the following environment variable is beneficial:

  export MKL_DEBUG_CPU_TYPE=5
  

  When using FFTW interface from MKL, please also set:

  export MKL_CBWR=AUTO
  

• If you use Jupyter notebooks, JupyterHub on Bell will only be available via the OnDemand Gateway rather than the freestanding version as on previous systems. Other RCAC systems will transition to OnDemand as well, following Bell.
• A subset of Bell compute nodes contain AMD Radeon Instinct MI50 accelerator cards which can significantly improve performance of compute-intensive workloads. These can be utilized by submitting jobs to the gpu queue (add -A gpu to your job submission command).
• A selection of GPU-enabled ROCm application containers from the AMD InfinityHub collection is installed.

Do I need to do anything to my firewall to access Bell?

No firewall changes are needed to access Bell. However, to access data through Network Drives (i.e., CIFS, "Z: Drive"), you must be on a Purdue campus network or connected through VPN.

Does Bell have the same home directory as other clusters?

The Bell home directory and its contents are exclusive to Bell cluster front-end hosts and compute nodes. This home directory is not available on other RCAC machines but Bell. There is no automatic copying or synchronization between home directories.

At your discretion you can manually copy all or parts of your main research computing home to Bell using one of the suggested methods.

If you plan to use hsi or htar commands to access Fortress tape archive from Bell, please see also the keytab generation question for a temporary workaround to a potential caveat, while a permanent mitigation is being developed.