iSCSI initiator and Dell PowerVault MD3000i

Wed Dec 16 07:20:12 UTC 2009

> Hi all,
> I am playing with iscsi_initiator on FreeBSD 7-STABLE and Dell 
> PowerVault MD3000i. This is the first time I am testing iSCSI...
> 
> Does anyone have FreeBSD's iSCSI initiator in production / heavy load? 
> Or does somebody have experiences with Dell MD3000i?
> 
> One thing is "poor performance" ~ 60 - 70MB/s depending on RAID level 
> used. (poor performance compared to plain SATA disk which have 110MB/s - 
> both tested for reading as it is our planned load - multimedia streaming 
> and downloads)
> 
> 
> The other thing is some problem with compatibility of initiator and Dell 
> MD3000i.
> 
> If I setup RAID 5 'Disk Group' consisted of 4x 1TB SATA drives (in 
> MD3000i) and then created for example 2 'Virtual Disks', both are 
> detected by iscontrol and added to /dev/ as da0 and da1, but da1 spams 
> log with messages like this:
> 
> Dec 15 04:00:38 dust kernel: da0 at iscsi0 bus 0 target 0 lun 0
> Dec 15 04:00:38 dust kernel: da0: <DELL MD3000i 0735> Fixed Direct 
> Access SCSI-5 device
> Dec 15 04:00:38 dust kernel: da1 at iscsi0 bus 0 target 0 lun 1
> Dec 15 04:00:38 dust kernel: da1: <DELL MD3000i 0735> Fixed Direct 
> Access SCSI-5 device
> Dec 15 04:00:38 dust iscontrol[48576]: cam_open_btl: no passthrough 
> device found at 0:0:2
> Dec 15 04:00:38 dust iscontrol[48576]: cam_open_btl: no passthrough 
> device found at 0:0:3
> Dec 15 04:00:39 dust kernel: (da1:iscsi0:0:0:1): READ(6)/WRITE(6) not 
> supported, increasing minimum_cmd_size to 10.
> Dec 15 04:00:39 dust kernel: (da1:iscsi0:0:0:1): READ(10). CDB: 28 0 0 0 
> 0 0 0 0 1 0
> Dec 15 04:00:39 dust kernel: (da1:iscsi0:0:0:1): CAM Status: SCSI Status 
> Error
> Dec 15 04:00:39 dust kernel: (da1:iscsi0:0:0:1): SCSI Status: Check 
> Condition
> Dec 15 04:00:39 dust kernel: (da1:iscsi0:0:0:1): ILLEGAL REQUEST asc:94,1
> Dec 15 04:00:39 dust kernel: (da1:iscsi0:0:0:1): Vendor Specific ASC
> Dec 15 04:00:39 dust kernel: (da1:iscsi0:0:0:1): Unretryable error
> Dec 15 04:00:40 dust kernel: (da1:iscsi0:0:0:1): READ(10). CDB: 28 0 c 
> 7f df ff 0 0 1 0
> Dec 15 04:00:40 dust kernel: (da1:iscsi0:0:0:1): CAM Status: SCSI Status 
> Error
> Dec 15 04:00:40 dust kernel: (da1:iscsi0:0:0:1): SCSI Status: Check 
> Condition
> Dec 15 04:00:40 dust kernel: (da1:iscsi0:0:0:1): ILLEGAL REQUEST asc:94,1
> Dec 15 04:00:40 dust kernel: (da1:iscsi0:0:0:1): Vendor Specific ASC
> Dec 15 04:00:40 dust kernel: (da1:iscsi0:0:0:1): Unretryable error
> Dec 15 04:00:41 dust kernel: (da1:iscsi0:0:0:1): READ(10). CDB: 28 0 0 0 
> 0 0 0 0 1 0
> 
> The message repeated many times.
> 
> If I created more 'Virtual Disks' (7 for example), 3 of them are 
> producing same errors (da1, da3, da5)
> 
> If there is only one 'Virtual Disk', it seems fine... until I configured 
> second path to the virtual disk as I want to try gmultipath or geom_fox 
> (MD3000i is dual controller with 4 NICs), then second session produces 
> same errors.
> 
> First path - OK:
> 
> Dec 15 22:47:57 dust kernel: da0 at iscsi0 bus 0 target 0 lun 0
> Dec 15 22:47:57 dust kernel: da0: <DELL MD3000i 0735> Fixed Direct 
> Access SCSI-5 device
> Dec 15 22:47:57 dust iscontrol[52226]: cam_open_btl: no passthrough 
> device found at 0:0:1
> Dec 15 22:47:57 dust iscontrol[52226]: cam_open_btl: no passthrough 
> device found at 0:0:2
> Dec 15 22:47:57 dust iscontrol[52226]: cam_open_btl: no passthrough 
> device found at 0:0:3
> 
> 
> Second path - error:
> 
> Dec 15 22:48:04 dust kernel: da1 at iscsi0 bus 0 target 1 lun 0
> Dec 15 22:48:04 dust kernel: da1: <DELL MD3000i 0735> Fixed Direct 
> Access SCSI-5 device
> Dec 15 22:48:05 dust kernel: (da1:iscsi0:0:1:0): READ(6)/WRITE(6) not 
> supported, increasing minimum_cmd_size to 10.
> Dec 15 22:48:05 dust kernel: (da1:iscsi0:0:1:0): READ(10). CDB: 28 0 0 0 
> 0 0 0 0 1 0
> Dec 15 22:48:05 dust kernel: (da1:iscsi0:0:1:0): CAM Status: SCSI Status 
> Error
> Dec 15 22:48:05 dust kernel: (da1:iscsi0:0:1:0): SCSI Status: Check 
> Condition
> Dec 15 22:48:05 dust kernel: (da1:iscsi0:0:1:0): ILLEGAL REQUEST asc:94,1
> Dec 15 22:48:05 dust kernel: (da1:iscsi0:0:1:0): Vendor Specific ASC
> Dec 15 22:48:05 dust kernel: (da1:iscsi0:0:1:0): Unretryable error
> Dec 15 22:48:05 dust iscontrol[52230]: cam_open_btl: no passthrough 
> device found at 0:1:1
> Dec 15 22:48:05 dust iscontrol[52230]: cam_open_btl: no passthrough 
> device found at 0:1:2
> Dec 15 22:48:05 dust iscontrol[52230]: cam_open_btl: no passthrough 
> device found at 0:1:3
> Dec 15 22:48:06 dust kernel: (da1:iscsi0:0:1:0): READ(16). CDB: 88 0 0 0 
> 0 1 5d 21 1f ff 0 0 0 1 0 0
> Dec 15 22:48:06 dust kernel: (da1:iscsi0:0:1:0): CAM Status: SCSI Status 
> Error
> Dec 15 22:48:06 dust kernel: (da1:iscsi0:0:1:0): SCSI Status: Check 
> Condition
> Dec 15 22:48:06 dust kernel: (da1:iscsi0:0:1:0): ILLEGAL REQUEST asc:94,1
> Dec 15 22:48:06 dust kernel: (da1:iscsi0:0:1:0): Vendor Specific ASC
> Dec 15 22:48:06 dust kernel: (da1:iscsi0:0:1:0): Unretryable error
> Dec 15 22:48:07 dust kernel: (da1:iscsi0:0:1:0): READ(10). CDB: 28 0 0 0 
> 0 0 0 0 1 0
> Dec 15 22:48:07 dust kernel: (da1:iscsi0:0:1:0): CAM Status: SCSI Status 
> Error
> Dec 15 22:48:07 dust kernel: (da1:iscsi0:0:1:0): SCSI Status: Check 
> Condition
> Dec 15 22:48:07 dust kernel: (da1:iscsi0:0:1:0): ILLEGAL REQUEST asc:94,1
> Dec 15 22:48:07 dust kernel: (da1:iscsi0:0:1:0): Vendor Specific ASC
> Dec 15 22:48:07 dust kernel: (da1:iscsi0:0:1:0): Unretryable error
> Dec 15 22:48:09 dust kernel: (da1:iscsi0:0:1:0): READ(10). CDB: 28 0 0 0 
> 0 1 0 0 1 0
> 
> 
> # main path
> storage_1 {
>          initiatorname   = iqn.2005-01.il.ac.huji.cs::dust.example.com
>          TargetName      = 
> iqn.1984-05.com.dell:powervault.md3000i.60026b900042587b000000004ae58efc
>          TargetAddress   = 192.168.130.101:3260,1
>          tags            = 64
> }
> 
> # second path
> storage_2 {
>          initiatorname   = iqn.2005-01.il.ac.huji.cs::dust.example.com
>          TargetName      = 
> iqn.1984-05.com.dell:powervault.md3000i.60026b900042587b000000004ae58efc
>          TargetAddress   = 192.168.132.102:3260,2
>          tags            = 64
> }
> 
> Can somebody advice some tweaks to get better performance and solution 
> of the errors above?

hi Miroslav,
firstly, in case you haven't yet, get the latest from:
	ftp://ftp.cs.huji.ac.il/users/danny/freebsd/iscsi-2.2.3.tar.gz
the slowness is probably due to the scsi errors, which I need some scsi expert
(hence the cc to scsi at freebsd.org, hint, hint).
In the mean time, and if you can/want, you can allow me access to an iscsi 
partition
so that I can better debug the issue.
oh, and yes, we use it here.

	danny