Re: ASM bug?
From: Andrew Kerber <andrew.kerber_at_gmail.com>
Date: Thu, 2 Oct 2014 10:06:02 -0500
Message-Id: <DF739E16-4BB0-4A32-AF09-39426AD20C85_at_gmail.com>
Sounds like a bug. If she is using ASMLIB, she does not use Udev. The two are mutually exclusive.
>>> On 10/1/2014 4:27 PM, Dimensional DBA wrote:
>>> What Multipathing SW are you using?
>>>
>>> Matthew Parker
>>> Chief Technologist
>>> 425-891-7934 (cell)
>>> Dimensional.dba_at_comcast.net
>>> View Matthew Parker's profile on LinkedIn
>>>
>>>
>>> -----Original Message-----
>>> From: Dimensional DBA [mailto:dimensional.dba_at_comcast.net]
>>> Sent: Wednesday, October 01, 2014 5:23 PM
>>> To: 'maureen.english_at_alaska.edu'; 'oracle-l_at_freelists.org'
>>> Subject: RE: ASM bug?
>>>
>>> Did you put the disk id's in the multipath.conf file which hard sets the
>>> mapping?
>>>
>>>
>>> Matthew Parker
>>> Chief Technologist
>>> 425-891-7934 (cell)
>>> Dimensional.dba_at_comcast.net
>>> View Matthew Parker's profile on LinkedIn
>>>
>>>
>>> -----Original Message-----
>>> From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]
>>> On Behalf Of Maureen English
>>> Sent: Wednesday, October 01, 2014 4:44 PM
>>> To: oracle-l_at_freelists.org
>>> Subject: ASM bug?
>>>
>>> We're building a new system and the sysadmin and dba working on it
>>> discovered a problem.
>>> This is RHEL5 and Oracle 11.2.0.4 RAC.
>>>
>>> it has identified. It is not until ASM mounts the disks in a diskgroup that
>>> it marks them as "in use".
>>> device to a different disk before ASM mounts it.
>>> is very important not to flush a disk that ASM has already identified. Do
>>> not use multipath -F if there are any unmounted ASM disks presented to the
>>> system.
>>>
>>> Is this a known bug, or are there some rules regarding ASM and multipath
>>> that we missed?
>>>
>>> I'm not actually working on this system, but thought it sounds like
>>> something others would have encountered. I'm still searching through
>>> Metalink docs....
>>>
>>> - Maureen
>>>
>>> --
>>> http://www.freelists.org/webpage/oracle-l
>>>
>>>
Date: Thu, 2 Oct 2014 10:06:02 -0500
Message-Id: <DF739E16-4BB0-4A32-AF09-39426AD20C85_at_gmail.com>
Sounds like a bug. If she is using ASMLIB, she does not use Udev. The two are mutually exclusive.
Sent from my iPhone
> On Oct 2, 2014, at 2:53 AM, Stefan Koehler <contact_at_soocs.de> wrote: > > Hi Maureen, > that's no bug. You have to use persistent device naming (multipath binding) by multipathd and udev rules to set the correct device permission / owner. > > However be aware of the suggested multipath settings by every storage vendor (e.g. fail_if_no_path with NetApp) and ASM. In some cases you are not able to flush the device map due to such suggestions after a path failure, even if the disk is not used by ASM anymore. > > Best Regards > Stefan Koehler > > Oracle p erformance consultant and researcher > http://www.soocs.de > >> Maureen English <maureen.english_at_alaska.edu> hat am 2. Oktober 2014 um 02:34 geschrieben: >> >> device-mapper-multipath >> >>
>>> On 10/1/2014 4:27 PM, Dimensional DBA wrote:
>>> What Multipathing SW are you using?
>>>
>>> Matthew Parker
>>> Chief Technologist
>>> 425-891-7934 (cell)
>>> Dimensional.dba_at_comcast.net
>>> View Matthew Parker's profile on LinkedIn
>>>
>>>
>>> -----Original Message-----
>>> From: Dimensional DBA [mailto:dimensional.dba_at_comcast.net]
>>> Sent: Wednesday, October 01, 2014 5:23 PM
>>> To: 'maureen.english_at_alaska.edu'; 'oracle-l_at_freelists.org'
>>> Subject: RE: ASM bug?
>>>
>>> Did you put the disk id's in the multipath.conf file which hard sets the
>>> mapping?
>>>
>>>
>>> Matthew Parker
>>> Chief Technologist
>>> 425-891-7934 (cell)
>>> Dimensional.dba_at_comcast.net
>>> View Matthew Parker's profile on LinkedIn
>>>
>>>
>>> -----Original Message-----
>>> From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]
>>> On Behalf Of Maureen English
>>> Sent: Wednesday, October 01, 2014 4:44 PM
>>> To: oracle-l_at_freelists.org
>>> Subject: ASM bug?
>>>
>>> We're building a new system and the sysadmin and dba working on it
>>> discovered a problem.
>>> This is RHEL5 and Oracle 11.2.0.4 RAC.
>>>
>>>> At boot, or when instructed to do so, Oracle ASM scans disks and >>>> creates an index of which ASM labels are on which disks, however it >>>> does not do anything to tell the kernel that it intends to use the disks
>>> it has identified. It is not until ASM mounts the disks in a diskgroup that
>>> it marks them as "in use".
>>>> Until a disk is actually in use (opened), the kernel will happily >>>> unmap or re-map dm devices that Oracle ASM has already scanned. Oracle >>>> ASM will try to modify the wrong disk if the kernel remaps an unused dm
>>> device to a different disk before ASM mounts it.
>>>> When multipath is run with the -F option, it will flush all multipath >>>> devices that are not in use. When multipath re-maps the devices, it >>>> may assign different device numbers to the disks it flushed. There is >>>> no way to tell Oracle ASM to forget about a label it has scanned >>>> without deleting the ASM labels off the disk or rebooting the system. It
>>> is very important not to flush a disk that ASM has already identified. Do
>>> not use multipath -F if there are any unmounted ASM disks presented to the
>>> system.
>>>
>>> Is this a known bug, or are there some rules regarding ASM and multipath
>>> that we missed?
>>>
>>> I'm not actually working on this system, but thought it sounds like
>>> something others would have encountered. I'm still searching through
>>> Metalink docs....
>>>
>>> - Maureen
>>>
>>> --
>>> http://www.freelists.org/webpage/oracle-l
>>>
>>>
>> >> -- >> Maureen English >> Lead Database Administrator >> University of Alaska >> Fairbanks, AK >> (907) 450-8329 > > >> -- http://www.freelists.org/webpage/oracle-l > -- http://www.freelists.org/webpage/oracle-l
-- http://www.freelists.org/webpage/oracle-lReceived on Thu Oct 02 2014 - 17:06:02 CEST