LSI 9211-9i flashed to IT mode: Drive numbering on backplane

[BlizzardX]

Hi

I'm still trying to solve my drive numbering problems with my LSI cards. They are 9211-8is flashed with the P20 IT firmware to drop the raid functions away and make them dumb HBAs for the OS to manage.

Currently, the way the drives are presented in the booted OS (doesn't matter if Windows or Linux) is different to the boot order and physical slot e.g.

Physical Slot 1 = Port 0
Physical Slot 2 = Port 1
etc.
Physical Slot 8 = Port 7

The above is what I see when I see the boot screen before the OS has loaded. The physical slots match the port numbers that they are plugged into.

Now when I load the OS, the order can be completly different e.g.

Physical Slot 1 = LSI Port 0 = sdc
Physical Slot 2 = LSI Port 1 = sda
etc.

Its important to note that I am currently using SATA break out cables without the sideband cable.

If I was to replace my current chassis with a fully compliant SES2 backplane chassis and run SFF-8087 cables with sideband (e.g. 36 pins) would that report the drive slot number back to the card so that when linux loads I would get the true setup

Physical Slot 1 = LSI Port 0 = sda
Physical Slot 2 = LSI Port 1 = sdb
etc.?

If not, is there anyway to get the LSI to report to the OS the correct drive number?

Thanks for any help.

Chris

 

[memyselfandi]

sdX devices are named by initial detection order in Linux not buy address (which is why they are not recommended in a lot of cases).

Dependent on your Linux distribution you may have devices under by-path and by-id directories under the /dev tree which allow you to link the devices at the Linux level with the physical addressing.

 

[BlizzardX]

I'm using a software raid stack currently, Linux's MDADM, which uses sdX as its identifier. I can do it all manually, but I wondered if a sideband enabled backplane with SFF-8087 cables would do it properly.

The main purpose is to move back to Xpenology which is the Synology NAS software running on a custom bootloader but as it uses MDADM it uses sdX as its hard drive ordering in the gui.

Synology do a SAS based rack running the same software using LSI 6G cards but this does drive ordering properly using the sdX method from what I can tell. The chassis is a 12 bay with dual SFF-8087 cables but it has two other cables running from the card to the backplane apparently... I'm trying to get some more photos of this so I can decipher what they're doing.

 

[BlizzardX]

I want to add that if anyone is using I2C cables too that would be good. Sideband uses SGPIO and the other way is the I2C connections. Both these methods should provide access to the LEDs etc. from the backplane, but they also appear to report whether the drive has a disk attached...