[dm-devel] Multipath-tools errors

Chandra Seetharaman sekharan at us.ibm.com
Thu Aug 16 18:23:33 UTC 2007 

On Thu, 2007-08-16 at 19:58 +0200, S. J. van Harmelen wrote:
> Hi Chandra,
> 
> Thanks for your reply! As far as I know it does use a LSI Engenio. I
> asked Dell if they can confirm this, but I didn't get any reply yet.
> Will get back with the answer as soon as I get it.
> 
My reply below is based on the assumption that it does use LSI Engenio.

> Besides that it seems to be working now. I don't have any errors anymore
> and it's not as slow as before. It's now doing something like 120M/sec,
> but don't know if thats good or not (don't know how fast this device
> should be)...
> 
> I did leave out the hardware_handler line because of the error it gives.
> But I understand that is because of my kernel? I'm using the package
> from Christophe's website version 0.4.8 on a Debian Etch 64bit machine
> with a 2.6.22.2 kernel.

Yes, you need a 2.6.23-rc1 (or upwards) kernel to have the rdac hardware
handler support.
> 
> I quess I need the hardware_handler to make it work as it should? Al

Yes, without the hardware handler, path failover/failback will not work.

> true it sees all paths and says that both active. Where one is
> active/ready and the other is active/ghost. 
> 
> Anything I can do about this? 

I do not understand the problem you are mentioning here. Will be easier
to follow if you can copy the o/p of "multipath -ll" and explain your
issue w.r.t that.

Also, attaching your multipath.conf would also be useful.

chandra
> 
> Sander
> 
> 
> 
> 
> 
> 
> On Thu, 2007-08-16 at 10:26 -0700, Chandra Seetharaman wrote:
> > First off, the "mpath_prio_rdac" is the path checker for the lsi engenio
> > controller. Is the Dell MD300 based on that controller ?
> > 
> > If it is _not_, then you should _not_ be using mpath_prio_rdac.
> > 
> > If it is, read on.
> > 
> > You need to use the hardware handler for the same controller, you can
> > setup your multipath.conf to use the "rdac" hardware handler.
> > 
> > Here is how your multipath.conf should look like:
> > -----------
> > devices {
> >         device {
> >                 vendor                  "$vendor_name"
> >                 product                 "$product_name"
> >                 hardware_handler        "1 rdac"
> >                 path_checker            rdac
> >                 path_grouping_policy    group_by_prio
> >                 prio_callout            "/sbin/mpath_prio_rdac /dev/%n"
> >         }
> > }
> > -----------
> > 
> > Note: replace $vendor_name and $product_name with appropriate vendor and
> > product information for the storage.
> > 
> > Hardware handler for rdac is available only in 2.6.23-rc1 and onwards
> > (if you are not using this version, do let me know which version of the
> > kernel you are using, even if it is in distro).
> > 
> > Where did you get the multipath-tools from ? From Christophe's website
> > or any distro(RedHat/SuSE) ?
> > 
> > And, as Malahal pointed, make sure you have /sbin/mpath_prio_rdac
> > available and is an executable.
> > 
> > Hope this helps,
> > 
> > chandra
> > On Fri, 2007-08-10 at 16:50 +0200, S. J. van Harmelen wrote:
> > > Oke, got a bit further...
> > > 
> > > I now understand how to use the disks. Only thing thats not going oke is
> > > that I get these errors constantly (while formatting):
> > > 
> > > end_request: I/O error, dev sdf, sector 30408704
> > > end_request: I/O error, dev sdf, sector 30670848
> > > end_request: I/O error, dev sdf, sector 30932992
> > > end_request: I/O error, dev sdf, sector 31195136
> > > end_request: I/O error, dev sdf, sector 31457280
> > > 
> > > or (while editting a file):
> > > 
> > > end_request: I/O error, dev sdc, sector 966656
> > > device-mapper: multipath: Failing path 8:32.
> > > end_request: I/O error, dev sdc, sector 966720
> > > device-mapper: multipath: Failing path 8:32.
> > > end_request: I/O error, dev sdc, sector 96665
> > > 
> > > And the device seems very slow...
> > > 
> > > And also stil having this error: "error calling out mpath_prio_rdac"
> > > 
> > > Any tips, pointers?
> > > 
> > > Sander
> > > 
> > > -------- Forwarded Message --------
> > > From: S. J. van Harmelen <svanharmelen at xillan.nl>
> > > To: dm-devel at redhat.com
> > > Subject: Re: Multipath-tools
> > > Date: Fri, 10 Aug 2007 11:47:01 +0200
> > > 
> > > Hi again,
> > > 
> > > Seem to have found the solution for the first question. Got
> > > multipath-tools up and running now :)
> > > 
> > > But please do answer the others questions if you have a minute to
> > > spare...
> > > 
> > > Also I'm seeing "error calling out mpath_prio_rdac" when starting
> > > multipathd?! Any word on that one?
> > > 
> > > Regards,
> > > 
> > > Sander
> > > 
> > > 
> > > 
> > > On Fri, 2007-08-10 at 10:27 +0200, S. J. van Harmelen wrote:
> > > > Hey guys,
> > > > 
> > > > Sorry to bother you, but I have a question I think you can answer. I
> > > > also send this message to Christophe, but I don't know how long he takes
> > > > to respond. I'm trying to set up a Dell NX1950 which has an RDAC MD300
> > > > array connected with linux.
> > > > 
> > > > Now I got all thinks working, but the RDAC driver. I'm trying to use the
> > > > opensource multipath-tools (which I want to compile myself), but I have
> > > > some questions about it:
> > > > 
> > > > 1) While compiling I get an error saying: "/usr/bin/ld: cannot find
> > > > -ldevmapper" Can you tell me what I can do to fix this error?
> > > > 
> > > > 2) Can you tell me if there is a mailinglist for the multipath-tools?
> > > > 
> > > > 3) Can you point me to some documentation about configuring the
> > > > multipath-tools with the new RDAC path checker?
> > > > 
> > > > Thanks very much for your time!
> > > > 
> > > > Kind regards,
> > > > 
> > > > Sander van Harmelen
> > > 
> > > --
> > > dm-devel mailing list
> > > dm-devel at redhat.com
> > > https://www.redhat.com/mailman/listinfo/dm-devel
> > -- 
> > 
> > ----------------------------------------------------------------------
> >     Chandra Seetharaman               | Be careful what you choose....
> >               - sekharan at us.ibm.com   |      .......you may get it.
> > ----------------------------------------------------------------------
> > 
> > 
> > --
> > dm-devel mailing list
> > dm-devel at redhat.com
> > https://www.redhat.com/mailman/listinfo/dm-devel
> 
-- 

----------------------------------------------------------------------
    Chandra Seetharaman               | Be careful what you choose....
              - sekharan at us.ibm.com   |      .......you may get it.
----------------------------------------------------------------------

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