openhpc
NFS mount shadows software installed on the image.
I was following the CentOS7.5 Base OS xCAT/SLURM Edition for Linux* (x86 64).
At 3.9.2 Add OpenHPC Components the document instruct for installation of some packages on the image, but at 3.9.3 Customize system configuration the document instruct for mount ${sms_ip}:/opt/ohcp/pub at /opt/ohpc/pub in the computing nodes.
This make the contents of /opt/ohpc/pub on the computing nodes to be shadowed by the contents of the same folder on the management node. This will only be a problem if afterwards the user install something that goes to /opt/ohpc/pub in the image, which would be uncommon. Anyway, in this case it would fail silently until the user try to access the same contents on that mount point when it will face something like No such file or directory.
Besides failing slowly and silently it will also waste memory space on stateless images, which is the worse drawback.
How to approach this? Regards,
I think part of the thought here is on the choice of stateless/stateful. If you are stateless, then you likely want to keep the compute image fairly small and hence install most of the development oriented tools on the head node and NFS share /opt/ohpc/pub with the computes. If you are truly stateful, then you are likely not limited on available space locally and can instead splat the development content onto each node. In that the case, the thought was that you would not need to NFS mount /opt/ohpc/pub.
Hi @koomie! Thanks for the answer!
Yeah I was just thinking that. For stateless use only NFS share and don't install stuff on the image itself. This will make it have a smaller footprint, saving valuable memory space. The documentation is misleading in this aspect, it instructs user to install stuff on the image, and then instructing it to mount NFS over installed software.