iscsitarget configuration

SUSE Linux Enterprise Server SLES Configure-Administer
1

I’ve created a very simple configuration for iscsitarget (i.e., IET):

Target iqn.2012-11.com.example.san1:sda Lun 0 Path=/dev/drbd7,Type=blockio Lun 1 Path=/dev/drbd8,Type=blockio Lun 2 Path=/dev/drbd9,Type=blockio Lun 3 Path=/dev/drbd10,Type=blockio Target iqn.2012-11.com.example.san1:sdb Lun 0 Path=/dev/drbd107,Type=blockio
However, none of the LUN’s appear on the initiator:

xen1:~ # iscsiadm -m session -P3 iSCSI Transport Class version 2.0-870 version 2.0-872.suse Target: iqn.2012-11.com.example.san1:sdb Current Portal: 192.168.1.1:3260,1 Persistent Portal: 192.168.1.1:3260,1 ********** Interface: ********** Iface Name: default Iface Transport: tcp Iface Initiatorname: iqn.1996-04.de.suse:01:2441bbdc6224 Iface IPaddress: 192.168.1.3 Iface HWaddress: <empty> Iface Netdev: <empty> SID: 1 iSCSI Connection State: LOGGED IN iSCSI Session State: LOGGED_IN Internal iscsid Session State: NO CHANGE ********* Timeouts: ********* Recovery Timeout: 120 Target Reset Timeout: 30 LUN Reset Timeout: 30 Abort Timeout: 15 ***** CHAP: ***** username: <empty> password: ******** username_in: <empty> password_in: ******** ************************ Negotiated iSCSI params: ************************ HeaderDigest: None DataDigest: None MaxRecvDataSegmentLength: 262144 MaxXmitDataSegmentLength: 8192 FirstBurstLength: 65536 MaxBurstLength: 262144 ImmediateData: Yes InitialR2T: Yes MaxOutstandingR2T: 1 ************************ Attached SCSI devices: ************************ Host Number: 6 State: running Target: iqn.2012-11.com.example.san1:sda Current Portal: 192.168.1.1:3260,1 Persistent Portal: 192.168.1.1:3260,1 ********** Interface: ********** Iface Name: default Iface Transport: tcp Iface Initiatorname: iqn.1996-04.de.suse:01:2441bbdc6224 Iface IPaddress: 192.168.1.3 Iface HWaddress: <empty> Iface Netdev: <empty> SID: 2 iSCSI Connection State: LOGGED IN iSCSI Session State: LOGGED_IN Internal iscsid Session State: NO CHANGE ********* Timeouts: ********* Recovery Timeout: 120 Target Reset Timeout: 30 LUN Reset Timeout: 30 Abort Timeout: 15 ***** CHAP: ***** username: <empty> password: ******** username_in: <empty> password_in: ******** ************************ Negotiated iSCSI params: ************************ HeaderDigest: None DataDigest: None MaxRecvDataSegmentLength: 262144 MaxXmitDataSegmentLength: 8192 FirstBurstLength: 65536 MaxBurstLength: 262144 ImmediateData: Yes InitialR2T: Yes MaxOutstandingR2T: 1 ************************ Attached SCSI devices: ************************ Host Number: 7 State: running
Why aren’t the LUN’s visible to the initiator?

Eric P.
Truckee, CA

2

Reloading iscsitarget on the SAN…

[CODE]> san1:~ # /etc/init.d/iscsitarget reload

Stopping iSCSI target service: done
Starting iSCSI target service: done[/CODE]
…and then clearing the initiator database…

[CODE]xen1:~ # iscsiadm -m discovery --op=delete -p 192.168.1.1

xen1:~ # iscsiadm -m discovery -t st -p 192.168.1.1
192.168.1.1:3260,1 iqn.2012-11.com.example.san1:sdb
192.168.0.1:3260,1 iqn.2012-11.com.example.san1:sdb
192.168.1.1:3260,1 iqn.2012-11.com.example.san1:sda
192.168.0.1:3260,1 iqn.2012-11.com.example.san1:sda

xen1:~ # iscsiadm -m node -p 192.168.1.1 -l
Logging in to [iface: default, target: iqn.2012-11.com.example.san1:sdb, portal: 192.168.1.1,3260] (multiple)
Logging in to [iface: default, target: iqn.2012-11.com.example.san1:sda, portal: 192.168.1.1,3260] (multiple)
Login to [iface: default, target: iqn.2012-11.com.example.san1:sdb, portal: 192.168.1.1,3260] successful.
Login to [iface: default, target: iqn.2012-11.com.example.san1:sda, portal: 192.168.1.1,3260] successful.

xen1:~ # dmesg | tail
[16159.158419] sd 9:0:0:3: [sdf] Write cache: disabled, read cache: disabled, doesn’t support DPO or FUA
[16159.158978] sd 8:0:0:0: [sdb] Attached SCSI disk
[16159.180750] sdc: unknown partition table
[16159.182476] sd 9:0:0:0: [sdc] Attached SCSI disk
[16159.196576] sdd: unknown partition table
[16159.198112] sd 9:0:0:1: [sdd] Attached SCSI disk
[16159.229768] sde: unknown partition table
[16159.231276] sd 9:0:0:2: [sde] Attached SCSI disk
[16159.238949] sdf: unknown partition table
[16159.240762] sd 9:0:0:3: [sdf] Attached SCSI disk

xen1:~ # lsscsi
[0:0:0:0] disk ATA HDS728080PLA380 PF2O /dev/sda
[4:0:1:0] cd/dvd HL-DT-ST RW/DVD GCC-4244N 1.00 /dev/sr0
[8:0:0:0] disk IET VIRTUAL-DISK 0 /dev/sdb
[9:0:0:0] disk IET VIRTUAL-DISK 0 /dev/sdc
[9:0:0:1] disk IET VIRTUAL-DISK 0 /dev/sdd
[9:0:0:2] disk IET VIRTUAL-DISK 0 /dev/sde
[9:0:0:3] disk IET VIRTUAL-DISK 0 /dev/sdf [/CODE]
…seems to have fixed the problem.

Could this be an issue of timing? i.e., Could iscsitarget be trying to export the block devices before DRBD is ready?

Eric P.
Truckee, CA

3

I left out a very important step (above): I realized afterwards that the exported devices were DRBD devices and that none of the DRBD devices were ready:

[CODE]> san1:/usr/share/doc # cat /proc/drbd

version: 8.4.1 (api:1/proto:86-100)
GIT-hash: 91b4c048c1a0e06777b5f65d312b38d47abaea80 build by phil@fat-tyre, 2011-12-20 12:43:15

7: cs:Connected ro:Secondary/Secondary ds:UpToDate/UpToDate C r-----
ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:0
8: cs:Connected ro:Secondary/Secondary ds:UpToDate/UpToDate C r-----
ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:0
9: cs:Connected ro:Secondary/Secondary ds:UpToDate/UpToDate C r-----
ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:0
10: cs:Connected ro:Secondary/Secondary ds:UpToDate/UpToDate C r-----
ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:0

107: cs:Connected ro:Secondary/Secondary ds:UpToDate/UpToDate C r-----
ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:0[/CODE]
So, after promoting SAN1 to become the primary, I reloaded iscsitarget on the SAN. i.e., drbd{7,8,9,10} had been read-only because SAN1 was not the primary.

I expect that if/when I figure out why SAN1 didn’t automatically become the primary the problem will be resolved.

Eric P.
Truckee, CA