Yesterday I had problems installing OMV on a new PC. I have some basic PC knowledge, but not being familiar with Linux, I had to do a fair amount of research. I believe I have corrected the problem and that the issue has more to do with the Linux kernal, than OMV, but I would appreciate your thoughts.
When I installed OMV without my LSI 9201 SAS HBA card installed, everything worked fine. After shutting down and installing the card, it wouldn't work and my onboard realtek gigabit NIC wouldn't work. So I tried reinstalling OMV with the LSI card present and during installation OMV couldn't detect my onboard NIC. So I tried to reinstall a couple different ways, but it was always the same. During boot I saw messages like this:
r8169 000:22:00.0: no MMIO resource found
xhci_hcd 0000:03:00.0: init 0000:03:00.0 fail
mpt2sas_cm0: unable to map adapter memory!
sp5100-tc0 sp5100-tc0: Watchdog hardware is disabled
Those messages indicated to me that there was some sort of resource conflict. So I did a bunch of other searching and found people with similar problems. I added the following kernal parameter pci=realloc=off during installation and everything was detected properly. I permanently added it to GRUB's configuration file and the system appears to be just fine? This "issue" appears to have noticed as early as 2015 as I found some people discussing it in regards to linux kernal 3.19 rc6 https://www.spinics.net/lists/linux-pci/msg38416.html
I also noticed that my onboard NIC was referred to as enp24s0 when the LSI care was not installed and then when using pci=realloc=off and the LSI card installed my onboard nic was then referred to as enp34s0.
So I suppose my questions are:
Why is my system doing this and why can't linux detect and allocate resources to my hardware properly (edited to add: don't want to come across like I'm just blaming Linux haha, perhaps my motherboard is causing the problem?) ?
Are there any negative effects for using pci=realloc=off in terms of stability, performance, etc?
I plan on using this system and OMV for many years to come, is this "fix" going to remain working or will it "break" sometime in the future leaving me stranded with non functional hardware?
Thank you very much for your thoughts on this.