Hello all !
Installation on baremetal on DELL R520 OK ! thx to @pocopico and @ThorGroup for the help.
Driver mpt2sas from pocopico works fine, just need to modify the synoinfo.conf like @Orphée (internalportcfg ; max disk and sataportmap/diskisxmap) to have all 8 disks visible.
The last thing to do is the dual CPU, not reconized for now, wait for @ThorGroup to modify microcode. Have tried, but result is very unstable/kernel panic lol.
Dell R520 performance are very increased to compare with virtual VMware VM.
Is there any chance to have a loader compatible with RX series ?
And for those wants to install baremetal on DELL server, the IPMI SOL works perfectly with redpill loader to debug. Last thing, I use Intel X520 pci adapter for network. The driver is include with the 3615xs and works perfectly
EDIT : Dual CPU is recognized but the kernel, limitation is only on core/thread. I've missed the CPU cores section in system info : "2 CPUs/4 Cores | 8 Threads"
The cat /proc/cpuinfo : Impossible to say if it use 2 CPU or not...