missing [iscsi_eh] process

[solidguy]

I downloaded and built the latest semi-stable build (870.3). I built
this on 3 different machines (A,B,C) all are supposedly Centos 2.6.18
(uname -r) . After make install and reboot, 2 of the machines (A&B)
have an [iscsi_eh] process, but the 3rd one does not. All modules
(*.ko) are the same size and iscsiadm -V reports "iscsiadm version
2.0-870". However all 3 machines are able to login to targets exported
by a solaris box. Is this OK? How do I go about debugging this?

The only difference on machine C is the output of lsmod | grep iscsi:
A&B:

iscsi_tcp 27280 0
libiscsi 38272 1 iscsi_tcp
scsi_transport_iscsi 41880 3 iscsi_tcp,libiscsi
scsi_mod 152240 10
iscsi_tcp,libiscsi,scsi_transport_iscsi,sr_mod,sg,mptsas,mptscsih,scsi_transport_sas,libata,sd_mod

C:
iscsi_tcp 29312 4
libiscsi 30080 2 ib_iser,iscsi_tcp
scsi_transport_iscsi 37016 4 ib_iser,iscsi_tcp,libiscsi
scsi_mod 152240 37
ib_iser,tmscsim,sym53c8xx,sr_mod,sg,scsi_transport_sas,raid_class,qla2xxx,qla1280,ppa,osst,megaraid_sas,megaraid_mbox,megaraid,lpfc,scsi_transport_fc,iscsi_tcp,libiscsi,scsi_transport_iscsi,imm,ide_scsi,hptiop,dmx3191d,dc395x,ch,BusLogic,atp870u,aic7xxx,aic79xx,scsi_transport_spi,ahci,aacraid,a100u2w,
3w_xxxx,3w_9xxx,libata,sd_mod

Apparently it is loading some other version (as far as I can tell make
install wiped out the previous version installed which was 868).

Thanks

[solidguy]

Fixed with
yum remove iscsi*
followed by
make install; chkconfig --add open-iscsi

[solidguy]

Spoke too soon. After reboot, it reverted to the previous behavior.
The message in /var/log/messages is:
Apr 5 22:52:47 test0 iscsid: transport class version 1.1-646. iscsid
version 2.0-870
vs
Apr 4 11:12:49 test2 kernel: Loading iSCSI transport class v2.0-870.

Is this because of the ib_iser module dependency in machine C (test0)?

[Ulrich Windl]

On 5 Apr 2009 at 23:46, solidguy wrote:

>
> Spoke too soon. After reboot, it reverted to the previous behavior.
> The message in /var/log/messages is:
> Apr 5 22:52:47 test0 iscsid: transport class version 1.1-646. iscsid
> version 2.0-870
> vs
> Apr 4 11:12:49 test2 kernel: Loading iSCSI transport class v2.0-870.
>
> Is this because of the ib_iser module dependency in machine C (test0)?

Hi,

AFAIK, "[scsi_eh_*]" threads are SCSI error handlers, one per target, I guess. I'm
running an older version of open-iscsi that shows no "iscsi_eh" processes/threads.
I could guess that you don't have an "_EH" thread when there was no target
discovered or session logged-in.

Regards,
Ulrich

[Mike Christie]

solidguy wrote:
> Spoke too soon. After reboot, it reverted to the previous behavior.
> The message in /var/log/messages is:
> Apr 5 22:52:47 test0 iscsid: transport class version 1.1-646. iscsid
> version 2.0-870
> vs
> Apr 4 11:12:49 test2 kernel: Loading iSCSI transport class v2.0-870.
>
> Is this because of the ib_iser module dependency in machine C (test0)?
>

Sort of.

The iscsi modules that come with Centos are older (1.1-646 based and
this is pretty old and you probably want to upgrade to Centos 5.3).
Those kernel iscsi modules did did not use a iscsi_eh thread. Instead
they used the system default one.

In newer iscsi modules like the ones that come with the open-iscsi
tarball that you get on open-iscsi.org uses a special iscsi_eh thread
(one for the entire iscsi module).

So it looks like in one box you are using the older modules, and in A
and B you are using the iscsi modules that came with open-iscsi.org tarball.

Doing a make install of the open-iscsi.org release normally will install
the open-iscsi.org modules. Install here means that it overwrites the
native kernel iscsi modules with its own.



ib_iser:
Do you need iser? If so then you need to use the iscsi kernel modules
that come with the kernel. The iscsi modules that come with
open-iscsi.org releases do not support iser.

[solidguy]

OK, it looks like the initrd has the older iscsi modules built-in and
hence the older ones show up on reboot despite the make install
[root@test0 ~]# strings initrd-2.6.18.8.img | grep 1.1-646
1.1-646
version=1.1-646


Thanks!