[Stgt-devel] disk kicked out of RAID -> tgtd segmentation fault

[Tomasz Chmielewski]

FUJITA Tomonori schrieb:
> On Wed, 09 Jul 2008 08:36:32 +0200
> Tomasz Chmielewski <mangoo at wpkg.org> wrote:
> 
>> FUJITA Tomonori schrieb:
>>> On Wed, 09 Jul 2008 08:03:05 +0200
>>> Tomasz Chmielewski <mangoo at wpkg.org> wrote:
>>>
>>>> FUJITA Tomonori schrieb:
>>>>> On Mon, 30 Jun 2008 10:54:48 +0200
>>>>> Tomasz Chmielewski <mangoo at wpkg.org> wrote:
>>>>>
>>>>>> Tomasz Chmielewski schrieb:
>>>>>>> ronnie sahlberg schrieb:
>>>>>>>> Hi Tomasz,
>>>>>>>>
>>>>>>>> I could not get that configuration to work.
>>>>>>>>
>>>>>>>> Can you please provide more detailed instructions exactly how to set
>>>>>>>> up hosts A B and C
>>>>>>>> so I can try to reproduce it.
>>>>>>>>
>>>>>>>> Please provide the exact commandline for each and every command I need
>>>>>>>> to run on the three hosts and Ill try to
>>>>>>>> reproduce it under gdb.
>>>>>>> A faulty RAID is just one way to crash tgtd.
>>>>>>>
>>>>>>> A simpler one is to just block the traffic between the target and the 
>>>>>>> initiator - just login to the target, make sure there is some iSCSI 
>>>>>>> traffic between the target and the initiator, then block incoming iSCSI 
>>>>>>> traffic on the initiator with:
>>>>>>>
>>>>>>> initiator# iptables -I INPUT -s <target IP> -p tcp --sport 3260 -j DROP
>>>>>>>
>>>>>>>
>>>>>>> After a while, you will see that only one tgtd process is running, 
>>>>>>> whereas the second has crashed.
>>>>>> Note - the above seems to be valid if:
>>>>>>
>>>>>> - there are two initiators connected (from different IPs), perhaps more
>>>>>> - there is traffic from these two initiators
>>>>>> - we block traffic on one of these initiators
>>>>>>
>>>>>>
>>>>>> I couldn't reproduce the issue with only one initiator connected.
>>>>> Can you provide the detailed configuration?
>>>>>
>>>>> Do you mean:
>>>>>
>>>>> 1. there are three machines, say A, B, and C.
>>>> yes
>>>>
>>>>> 2. you run tgtd on A and setup one target in tgtd.
>>>> yes
>>>>
>>>>> 3. B and C work as an initiator. They connect to A. So the target on A
>>>>> has two sessions.
>>>> yes
>>>>
>>>>> Then you block the traffic btwwen A and B, then tgtd on A dies?
>>>>>
>>>>> Right?
>>>> Yes, exactly like that.
>>>> I'm not sure if blocking traffic in both ways is needed, or is it 
>>>> sufficient/needed to block the traffic from the initiator to the target 
>>>> (and not from target to the initiator, i.e., -I OUTPUT chain).
>>> You block the traffic on the initiator and then on the target?
>> No, only on the initiator.
>>
>>
>>>>> I think that the output of tgtadm will enable us to understand your
>>>>> configuration easily.
>>>> What output?
>>> As I said, the output of tgtadm shows what tgtd has:
>>>
>>> Target 1: iqn.2001-04.org.osrg:viola
>>>     System information:
>>>         Driver: iscsi
>>>         State: ready
>> Aah, this output.
>>
>> Nothing special there - two targets configured, each target has one 
>> initiator coming from a different IP.
> 
> Two targets? Hmm, I thought that you have one target machine and
> configure one target object.
> 
> Please tell me about your target objects (configured in tgtd) and
> physical target machines.

One target machine with two (or more) targets configured, like below; 
here is the output - right now, only one initiator is connected; I can 
reproduce the issue when a second initiator connects, but I can't do it 
right now.

# tgtadm --lld iscsi --op show --mode target
Target 1: iqn.2006-08.net.syneticon:superthecus.backup
     System information:
         Driver: iscsi
         State: ready
     I_T nexus information:
         I_T nexus: 1
             Initiator: iqn.2006-12.net.syneticon:server.backup1
             Connection: 0
                 IP Address: 192.168.111.173
     LUN information:
         LUN: 0
             Type: controller
             SCSI ID: deadbeaf1:0
             SCSI SN: beaf10
             Size: 0 MB
             Online: Yes
             Removable media: No
             Backing store: No backing store
         LUN: 1
             Type: disk
             SCSI ID: deadbeaf1:1
             SCSI SN: beaf11
             Size: 1480476 MB
             Online: Yes
             Removable media: No
             Backing store: /dev/superthecus/backup
     Account information:
         backup
     ACL information:
         192.168.111.173
Target 2: iqn.2007-02.net.syneticon:superthecus.backup1
     System information:
         Driver: iscsi
         State: ready
     I_T nexus information:
     LUN information:
         LUN: 0
             Type: controller
             SCSI ID: deadbeaf2:0
             SCSI SN: beaf20
             Size: 0 MB
             Online: Yes
             Removable media: No
             Backing store: No backing store
         LUN: 1
             Type: disk
             SCSI ID: deadbeaf2:1
             SCSI SN: beaf21
             Size: 3221 MB
             Online: Yes
             Removable media: No
             Backing store: /dev/superthecus/backup1
     Account information:
     ACL information:
         ALL
Target 3: iqn.2008-06.net.syneticon:superthecus.test
     System information:
         Driver: iscsi
         State: ready
     I_T nexus information:
     LUN information:
         LUN: 0
             Type: controller
             SCSI ID: deadbeaf3:0
             SCSI SN: beaf30
             Size: 0 MB
             Online: Yes
             Removable media: No
             Backing store: No backing store
         LUN: 1
             Type: disk
             SCSI ID: deadbeaf3:1
             SCSI SN: beaf31
             Size: 2147 MB
             Online: Yes
             Removable media: No
             Backing store: /dev/superthecus/test
     Account information:
     ACL information:
         ALL


-- 
Tomasz Chmielewski
http://wpkg.org