[Stgt-devel] data corruption problems with stgt (aborted journal, remounting ro)?

[Tomasz Chmielewski]

FUJITA Tomonori schrieb:
> On Sat, 02 Feb 2008 10:39:02 +0100
> Tomasz Chmielewski <mangoo at wpkg.org> wrote:
> 
>> FUJITA Tomonori schrieb:
>>> On Fri, 01 Feb 2008 13:05:41 +0100
>>> Tomasz Chmielewski <mangoo at wpkg.org> wrote:
>>>
>>>> Tomasz Chmielewski schrieb:
>>>>> Doesn't look my posts get to this list... or is it just lagged a lot? 
>>>>> Resending.
>>>>>
>>>>>
>>>>> Perhaps I'm doing something wrong - but with stgt I'm facing problems I 
>>>>> didn't have with IET or SCST.
>>>>>
>>>>> Whenever I kill tgtd daemon and start it again (i.e., target server 
>>>>> restart), the initiator detects an aborted journal and remount the 
>>>>> device ro.
>>>>>
>>>>> Why is it so?
>>>>>
>>>>> What is the recommended way to kill the tgtd daemon? It doesn't seem to 
>>>>> react on TERM signal.
>>>> Hello, anyone there?
>>>>
>>>> Is there a way to restart tgtd daemon or a machine running tgtd, so that 
>>>> iSCSI connections don't break?
>>> What does your 'restart tgtd daemon' mean? For me, 'restart' involves
>>> stopping tgtd daemon and it closes all the iSCSI connections.
>> Stop it, and start again?
>>
>> Imagine you want to upgrade your tgtd daemon, a kernel running on that 
>> machine, or you have to restart the target machine for some other reason 
>> (i.e. your target machine died).
>>
>> With IET or SCST there is no problem with that - stop the target, and 
>> iSCSI initiator will try to reconnect.
> 
> How did you restart IET?
> 
> /etc/init.d/iscsi-target restart

Yes. Or restarting the whole machine if I changed the kernel (which 
would use the same iscsi-target script).

IET has some problems that it breaks when a number of initiators is 
bigger than 50 or so - which needs two workarounds (iptables, and 
increasing INCOMING_MAX in ietadm.h).

I described it a bit here:

http://blog.wpkg.org/2007/09/09/solving-reliability-and-scalability-problems-with-iscsi/


Restarting SCST works well, and doesn't need any workarounds.


But I also had one machine which was just hanging/freezing with IET 
every couple of weeks - just start the machine again, everything goes 
back to normal.


-- 
Tomasz Chmielewski