Unable to use persistent reservation on FC disks exposed from RHEV-M [3.3.0 version] (Host) to guest OS

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I have installed RHEV 6.5 on HOST system and using RHEV 3.3 hypervisor.
OS version: RHEV Hypervisor - 6.5 - 20141017.0.el6ev
Kernel version: .6.32 - 431.37.1.el6.x86_64
KVM version: 0.12.1.2 - 2.415.el6_5.14

RHEV-M version: rhevm-3.3.3-0.52.el6ev.noarch

I have exposed two FC disks from host to guest OS (RHEL 6.5) one from 3 PAR array and another from EVA disk array.
I am trying to use persistent reservation (iscsi) command but command is failing.

Please guide me to fix this problem.

On host (host1) persistent reservation is working but in guest system (guest1) persistent reservation command failed.

On host:

[root@host1 ~]# sg_persist -k /dev/sdj -vvv
open /dev/sdj with flags=0x800
inquiry cdb: 12 00 00 00 24 00
duration=23 ms
HP HSV300 0953
Peripheral device type: disk
open /dev/sdj with flags=0x802
Persistent Reservation In cmd: 5e 00 00 00 00 00 00 20 00 00
duration=0 ms
persistent reservation in: Fixed format, current; Sense key: Unit Attention
Additional sense: Power on, reset, or bus device reset occurred
Info fld=0x0 [0]
Raw sense data (in hex):
f0 00 06 00 00 00 00 07 00 00 00 00 29 00 00
requested 8192 bytes but got 0 bytes
PR in: unit attention

[root@host1 ~]# sg_persist -k /dev/sdb -vvv
open /dev/sdb with flags=0x800
inquiry cdb: 12 00 00 00 24 00
duration=0 ms
3PARdata VV 3122
Peripheral device type: disk
open /dev/sdb with flags=0x802
Persistent Reservation In cmd: 5e 00 00 00 00 00 00 20 00 00
duration=1 ms
persistent reservation in: requested 8192 bytes but got 8 bytes
persistent reserve in: response
00 00 00 00 00 00 00 00
PR generation=0x0, there are NO registered reservation keys


On Guest:

guest1:~ # sg_persist -k /dev/sdc
HP HSV300 0953
Peripheral device type: disk
PR in: aborted command
node1:~ # sg_persist -k /dev/sdb
3PARdata VV 3122
Peripheral device type: disk
PR in: aborted command

guest1:~ # sg_persist -k /dev/sdb -vvv
open /dev/sdb with flags=0x800
inquiry cdb: 12 00 00 00 24 00
duration=0 ms
3PARdata VV 3122
Peripheral device type: disk
open /dev/sdb with flags=0x802
Persistent Reservation In cmd: 5e 00 00 00 00 00 00 20 00 00
duration=0 ms
persistent reservation in: Fixed format, current; Sense key: Aborted Command
Additional sense: I/O process terminated
Raw sense data (in hex):
70 00 0b 00 00 00 00 0a 00 00 00 00 00 06 00 00
00 00
PR in: aborted command

guest1:~ # sg_persist -k /dev/sdc -vvv
open /dev/sdc with flags=0x800
inquiry cdb: 12 00 00 00 24 00
duration=0 ms
HP HSV300 0953
Peripheral device type: disk
open /dev/sdc with flags=0x802
Persistent Reservation In cmd: 5e 00 00 00 00 00 00 20 00 00
duration=4 ms
persistent reservation in: Fixed format, current; Sense key: Aborted Command
Additional sense: I/O process terminated
Raw sense data (in hex):
70 00 0b 00 00 00 00 0a 00 00 00 00 00 06 00 00
00 00
PR in: aborted command

Responses

Interesting question!

What are you implementing? (a cluster with Fencing?) Or what are you trying to accomplish? Perhaps there is another method someone can recommend.

How are you presenting the devices to the guest(s)? I.e. is it a passthru? I have managed to configure direct-passthru using KVM - I did not test any SCSI reservations though nor did I try this with RHEV/oVirt.

I did find this:
http://www.ovirt.org/Features/Virtio-SCSI

2) limited flexibility: virtio-blk does not support all possible storage scenarios. For example, it does not allow SCSI passthrough or persistent reservations. In principle, virtio-scsi provides anything that the underlying SCSI target (be it physical storage, iSCSI or the in-kernel target) supports. 

However, the Fedora documentation indicates it is possible (although they are not referring specifically to RHEV/oVirt)
http://fedoraproject.org/wiki/Features/virtio-scsi

virtio-scsi improves the storage stack in terms of scalability (easily overcomes the current limit of ~30 freely hot-pluggable/unpluggable storage devices), flexibility (support features such as SCSI passthrough or persistent reservations), extensibility (exposing new features to the guest does not require updating drivers in both the host and the guest).

Hopefully someone else can provide a more definitive answer whether this will work, or not.

Thanks James for helping me on this.

I am exposing (RHEV 6.5) host FC disks to guest OS using pass through (bus which I have selected is "virtio-scsi").
I have also done similar thing with (RHEL) KVM 6.5, it was working.

I am trying to configure a cluster on guest OS and want to use persistent reservation on exposed FC disks from host system (RHEV 6.5).

I have also read the article related to virtio-scsi some where it is written it is possible.

I would like to get some concrete answer from redhat team for below questions:
1. This kind of configuration is possible or not ?
2. If possible then what am I missing ?

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