I've been using Debian on Dell servers for many years.
For a long time I've been using the PERC H730P RAID controller, which is weel supported by utilities like MegaCLI.
Recently I've bought a R440 Server with the new H750 Raid controller.
I've initially been able to install Debian 11 on logical volumes created from the "BIOS" System Setup.
But after a few minutes/hours of using the server to configure the software side, the disks suddenly disappeared.
At boot, Grub was still working, but the Debian boot sequence would stop, unable to find partitions.
The LifeCycleController wouldn't report any hardware issue. But the « Support Live Image » (a liveCD provided by Dell) would not see any storage controller.
The tech support told me that this new RAID controller is not compatible with Debian (nor CentOS 7, which is on the SLI liveCD), and I have to ask for a replacement by an older but compatible H730P.
I'm writting this because I couln't find anything online regarding Debian compatibility with recent Dell Raid controllers.
Hope this helps.
Update 2022-01-31
I've managed to reinstall a fresh Debian 11.2 without issues.
I have then installed a backported 5.15.5 kernel (over the default 5.10.0). Everything seems fine.
But, when I install MegaCLI, the installation process freezes the whole server. After many Ctrl-C and a few minutes later, I get a shell back.
"megaclisas-status" hangs on "-- Controller information --".
After a round of Ctrl-C, I get the shell back.
If I try to purge the "megaclisas-status" and "megacli" packages, everything is frozen again.
I've just opened an issue on their tracker : https://github.com/eLvErDe/hwraid/issues/130
Update 2022-02-01:
My issue ha been rejected, stating that this is a kernel issue.
I've reinstalled all the OS with the 5.15 kernel, and did a bunch of stress test and benchmarks. Everything seems to be OK.
Then I've installed the "megacli" tool and used it with a few commands ; no issue.
Then I've installed the "megaclisas-status" package, and the server freezes when installing the package. After a hard-reboot, I can use the system again, but the "megaclisas-status" package is not installed.