[ovirt-users] Update to 3.5.1 scrambled multipath.conf?

[Fabian Deutsch]

----- Original Message -----
> ----- Original Message -----
> > From: "Dan Kenigsberg" <danken at redhat.com>
> > To: "Gianluca Cecchi" <gianluca.cecchi at gmail.com>, nsoffer at redhat.com
> > Cc: "users" <users at ovirt.org>, ykaplan at redhat.com
> > Sent: Monday, January 26, 2015 2:09:23 PM
> > Subject: Re: [ovirt-users] Update to 3.5.1 scrambled multipath.conf?
> > 
> > On Sat, Jan 24, 2015 at 12:59:01AM +0100, Gianluca Cecchi wrote:
> > > Hello,
> > > on my all-in-one installation @home I had 3.5.0 with F20.
> > > Today I updated to 3.5.1.
> > > 
> > > it seems it modified /etc/multipath.conf preventing me from using my
> > > second
> > > disk at all...
> > > 
> > > My system has internal ssd disk (sda) for OS and one local storage domain
> > > and another disk (sdb) with some partitions (on one of them there is also
> > > another local storage domain).
> > > 
> > > At reboot I was put in emergency boot because partitions at sdb disk
> > > could
> > > not be mounted (they were busy).
> > > it took me some time to understand that the problem was due to sdb gone
> > > managed as multipath device and so busy for partitions to be mounted.
> > > 
> > > Here you can find how multipath became after update and reboot
> > > https://drive.google.com/file/d/0BwoPbcrMv8mvS0FkMnNyMTdVTms/view?usp=sharing
> > > 
> > > No device-mapper-multipath update in yum.log
> > > 
> > > Also it seems that after changing it, it was then reverted at boot again
> > > (I
> > > don't know if the responsible was initrd/dracut or vdsmd) so in the mean
> > > time the only thing I could do was to make the file immutable with
> > > 
> > > chattr +i /etc/multipath.conf
> > 
> > The "supported" method of achieving this is to place "# RHEV PRIVATE" in
> > the second line of your hand-modified multipath.conf
> > 
> > I do not understand why this has happened only after upgrade to 3.5.1 -
> > 3.5.0's should have reverted you multipath.conf just as well during each
> > vdsm startup.
> > 
> > The good thing is that this annoying behavior has been dropped from the
> > master branch, so that 3.6 is not going to have it. Vdsm is not to mess
> > with other services config file while it is running. The logic moved to
> > `vdsm-tool configure`
> > 
> > > 
> > > and so I was able to reboot and verify that my partitions on sdb were ok
> > > and I was able to mount them (for safe I also ran an fsck against them)
> > > 
> > > Update ran around 19:20 and finished at 19:34
> > > here the log in gzip format
> > > https://drive.google.com/file/d/0BwoPbcrMv8mvWjJDTXU1YjRWOFk/view?usp=sharing
> > > 
> > > Reboot was done around 21:10-21:14
> > > 
> > > Here my /var/log/messages in gzip format, where you can see latest days.
> > > https://drive.google.com/file/d/0BwoPbcrMv8mvMm1ldXljd3hZWnM/view?usp=sharing
> > > 
> > > 
> > > Any suggestion appreciated.
> > > 
> > > Current multipath.conf (where I also commented out the getuid_callout
> > > that
> > > is not used anymore):
> > > 
> > > [root at tekkaman setup]# cat /etc/multipath.conf
> > > # RHEV REVISION 1.1
> > > 
> > > blacklist {
> > >     devnode "^(sda|sdb)[0-9]*"
> > > }
> 
> 
> I think what happened is:
> 
> 1. 3.5.1 had new multipath version
> 2. So vdsm upgraded the local file
> 3. blacklist above was removed
>    (it should exists in /etc/multipath.bak)
> 
> To prevent local changes, you have to mark the file as private
> as Dan suggests.
> 
> Seems to be related to the find_multiapth = "yes" bug:
> https://bugzilla.redhat.com/show_bug.cgi?id=1173290

The symptoms above sound exactly liek this issue.
When find_multipahts is no (the default when the directive is not present)
I sthat all non-blacklisted devices are tried to get claimed, and this happened above.

Blacklisting the devices works, or adding "find_mutlipaths yes" should also work, because
in that case only device which have more than one path (or are explicitly named) will be
claimed by multipath.

My 2ct.

- fabian

> Ben, can you confirm that this is the same issue?
> 
> > > 
> > > defaults {
> > >     polling_interval        5
> > >     #getuid_callout          "/usr/lib/udev/scsi_id --whitelisted
> > > --replace-whitespace --device=/dev/%n"
> > >     no_path_retry           fail
> > >     user_friendly_names     no
> > >     flush_on_last_del       yes
> > >     fast_io_fail_tmo        5
> > >     dev_loss_tmo            30
> > >     max_fds                 4096
> > > }
> > 
> 
> Regards,
> Nir
> _______________________________________________
> Users mailing list
> Users at ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>