[ovirt-devel] [vdsm] Wrong default multipath configuration for EL6

[Patrick Hurrelmann]

On 29.07.2014 15:51, Nir Soffer wrote:
> ----- Original Message -----
>> From: "Patrick Hurrelmann" <patrick.hurrelmann at lobster.de>
>> To: vdsm-devel at lists.fedorahosted.org, devel at ovirt.org
>> Sent: Tuesday, July 29, 2014 4:43:36 PM
>> Subject: [vdsm] Wrong default multipath configuration for EL6
>>
>> Hi all,
>>
>> after suffering from boot-failures after kernel-updates on my EL6 hosts
>> (the ones that san boot via iscsi), I finally managed to locate the root
>> cause of the problem: the default values as set by vdsm are incorrect
>> for EL6 and prohibit a successful iscsi boot (the faulty multipath.conf
>>  gets embedded in the new initrd on a kernel update). Additionally the
>> following errors are repeatedly logged on all my hosts (device ids may
>> vary) with the default vdsm multipath config:
>>
>> device-mapper: table: 253:5: multipath: error getting device
>> device-mapper: ioctl: error adding target to table
>> device-mapper: table: 253:5: multipath: error getting device
>> device-mapper: ioctl: error adding target to table
>>
>> And it all boils down to the default value set for option getuid_callout
>> in multipath.conf. Vdsm sets it to the following:
>>
>> getuid_callout  "/sbin/scsi_id --whitelisted --replace-whitespace
>> --device=/dev/%n"
>>
>> According to the man-page and other docu the default value on EL6 is
>> "/lib/udev/scsi_id --whitelisted --device=/dev/%n". Although the binary
>> /sbin/scsi_id is a valid link to the target /lib/udev/scsi_id, the link
>> itself (/sbin/scsi_id) is _not_ included in the generated initrd. The
>> binary /lib/udev/scsi_id is indeed included and changing the default
>> config to use /lib/udev/scsi_id instead does make it all work again.
>> iscsi boot (after regenerating the initrd, as the multipath.conf is
>> embedded) is back to good and the previously logged device-mapper errors
>> are gone, too.
>>
>> Can someone please verify this and and apply the easy (attached) patch?
> 
> Thanks Patrick!
> 
> I'll look into this.
> 
> Would you open a bug for this issue, to help us track this issue?

BZ#1124450 created to track the issue.

Thanks,
Patrick

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