FreeNAS on Lenovo SR550 with MegaRaid 94XX card not working

[rohan.hills]

Hi, I have now wasted many hours on trying to get this Lenovo SR550 with MegaRAID 94XX cards to work with FreeNAS. I know the hardware is working as expected however i cannot for the life of me get FreeNAS to see the Raid Controller and/or the Hard drives. I have the drives configured as JBOD inside the controller but they simply do not appear to the OS

I have completely lost my cool with this situation and am asking if anyone has any suggestions at all PLEASE...

 

[joeinaz]

What type of disks are you using and how many are you using? It's possible FreeNAS doesn't recognize the MegaRAID 94xx chipset or has no drivers. There are low cost controller alternatives depending of your drive configuration and quantities. Also, is the system still under warranty?

 

[Arwen]

Please note that using a hardware RAID controllers, like the MegaRAID, is not recommended. This is due to the disks not showing up as disks, but LUNs. And yes, JBOD mode on this RAID controller almost certainly shows up to the OS as a LUN. ZFS does not do well when it can not talk to the disks directly to spare out failing or failed sectors. And FreeNAS does not do well if it can't run SMART against the LUNs.

That said, there is a method to cause the MegaRAID to expose the disks as disks, not LUNs. I don't have the information handy, except that I think you have to force FreeNAS to use a different device driver for the MegaRAID controller. (Again, I don't know HOW...)

 

[rohan.hills]

Yeah, the problem seems to be that FreeNAS isn't loading any drivers for the card at all. If i do an lspci -v i can see the card is physically there but i am not seeing any drivers being loaded. As an experiment i also just loaded up a live CD of the latest CentOS and it can't see the disks either.

I have also switched out the RAID card for the lower spec version of the card from another machine and it is also not visible (mind you it is the same age as the first card i tried).

Reading around on a few of the other Distro forums it seems that this card might not be supported across any platform at this point unless using the absolute bleeding edge Kernel... For something that is going to be put into production this is not something we can do.. and we certainly can not risk running up a custom kernel etc.

Any help or advise would be greatly appreciated.

 

[kdragon75]

Buy an appropriate HBA and do not use anything with RAID in the name.

 

[rohan.hills]

Been doing some research and it appears that the Lenovo 430-8i might be suitable - it is a non-raid HBA however my concern is that will it still need a driver of sorts to make it work. Will that driver be listed as suitable for FreeNAS. Seriously this has been a nightmare..

 

[kdragon75]

looks like a Broadcom SAS3408 chipset and searching "Broadcom SAS3408 BSD driver" provides https://www.freebsd.org/cgi/man.cgi?query=mpr&sektion=4

 

[Ericloewe]

Fancy. NVMe + SAS + SATA. The backplanes to fully take advantage of that must cost a fortune.

 

[Arwen]

Fancy. NVMe + SAS + SATA. The backplanes to fully take advantage of that must cost a fortune.

Probably. Hopefully the price will come done.

One thing to note is that some of the newer LSI / Broadcom / Avago SAS chips directly support NVMe. Meaning the same lanes used by one disk for SAS, can be used by a NVMe for PCIe. I guess yet another encapsulation like SATA over SAS. (At least that is how I understand it...)

For those that don't know, if a SAS expander has a SATA disk attached, it will tunnel / encapsulate the SATA protocol over a SAS packet. But, if the SATA disk is directly connected to a SAS HBA's port, then the port turns into a SATA port for the duration. All part of the backwards compatibility built into SAS, since SATA came out first.

 

[Ericloewe]

Meaning the same lanes used by one disk for SAS, can be used by a NVMe for PCIe. I guess yet another encapsulation like SATA over SAS. (At least that is how I understand it...)

I seem to recall some Broadcom document that said that an SAS lane was needed for SAS/SATA and PCIe separately for NVMe.

What's interesting is that that the backplane connector, SFF-8639 (also known as U.2), has a completely separate set of pins for PCIe. It was a somewhat odd choice, since I can't really see any scenario where running PCIe and SAS/SATA to a disk is useful. It should allow for PCIe x5 SSDs, however, if anyone bothers with that option.