Re: Image Catalog over NFS

Hello Diego,

Am 09.12.2024 um 19:03 schrieb Diego E. KESSELMAN <diegokesselman@xxxxxxxxx>:

When we have more than 500GB I prefer to create a GO SAVE 22 to the Remote Optical Image Catalog + QGPL + QUSRSYS , and option 23 to a Virtual Tape Image Catalog , just because it is faster.

I presume this is also more error prone when trying to automate, yes?

But the option 21 works, slow but works.

Slow in which regard? IPL? Restore?

I usually extract the files using the VFYIMGCLG to a local IFS directory , create a .tar file with all the files I need and set the TFTPD server.

Thanks for the hint!

It is important to use a Linux distribution you know and control. Some distributions use NFS on TCP, not UDP, or force NFS V4. You need NFS V3 with UDP .

As far as I'm aware, at least for Debian, the default is to accept whatever the client asks for.

I guess you have dealed with that to create the NFS server for backups.

Not really. It just worked out of the box. Just put the right flags between the braces in /etc/exports. (rw,no_root_squash,no_subtree_check,async)

Async gives a huge increase in write performance for some workloads, so I tend to add it in any case, when writing is mandatory. Drawback is a certain chance to data loss when the NFS server machine fails. A risk I take, especially for a backup machine.

I suggest to avoid using compression, but you can compress the ISO images once you have finished. ZSTD is a great option.

Yeah, a cronjob can take care about this easily during the day.

Good luck with this "journey".

Thanks a lot!

Your Initial work some years ago was the primary inspiration for me to take the time and learn how to deal with this. After working with real tape (libraries) became less and less of an option the more we thought it through.

:wq! PoC