[dm-devel] No SAS end device

[Goktug YILDIRIM]

Hi,

This is my first post to list. I apologise if I fail to follow a proper way to ask for help.

I have a weird problem which makes me spend days to solve. But at the end I finished-up with no clues.

My linux distro is arch linux. And the kernel is 4.12.8-1.
Multipath tools version is v0.6.4 (03/11, 2016).

Also multipath.conf is below.
defaults {
	find_multipaths yes
	user_friendly_names no
}

blacklist {
}

I have a dual port LSI controller (LSISAS3008: FWVersion(13.00.00.00), ChipRevision(0x02), BiosVersion(15.00.02.00)).

My LSI HBA is connected to a super micro JBOD with dual cables. At the LSI BIOS I easily confirm that drives appear in a multipath way.

To simplify the problem I left to only two drives inserted. Both of them are Seagate SAS drives but in different models.

Seagate model number ST6000NM0034 works with multipath. However model number ST6000NM0095 simply DOES NOT! Firmwares (hba & drives) are up to date.

multipath -v2 ends up for ST6000NM0095 as below.
Aug 24 21:54:13 | sdt: No SAS end device for 'end_device-12:1'
Aug 24 21:54:13 | sdai: No SAS end device for 'end_device-12:3'
Aug 24 21:54:13 | 35000c50093cb203b: ignoring map


I’ve tried same setup with Centos 7 (kernel 3.x) and multipath works for both of the drives. This seems to be somewhat distro problem but since arch linux always uses vanilla sources I guess it would be good start to ask for help here.
I’ve searched a lot and there are lots of “ No SAS end device” messages. However I failed to find a matching with my issue.

Since I am a multipath newbie any guide would be valuable.

Thanks in advance.
-Goktug Yildirim