Bug 1906073

Summary: [RFE] Add more details in multipath.conf documentation/manual page regarding checker_timeout information
Product: Red Hat Enterprise Linux 8 Reporter: Robert Palco <rpalco>
Component: device-mapper-multipathAssignee: Ben Marzinski <bmarzins>
Status: CLOSED ERRATA QA Contact: Lin Li <lilin>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 8.3CC: agk, bmarzins, heinzm, lilin, msnitzer, prajnoha, zkabelac
Target Milestone: rcKeywords: FutureFeature, Triaged
Target Release: 8.0   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: device-mapper-multipath-0.8.4-7.el8 Doc Type: No Doc Update
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2021-05-18 15:06:46 UTC Type: Feature Request
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Comment 3 Ben Marzinski 2020-12-16 19:19:21 UTC 
The new section for checker_timeout says:

Specify the timeout to use for path checkers and prioritizers, in seconds. Only prioritizers that issue scsi commands use checker_timeout. Checkers that support an asynchronous mode (tur and directio), will return shortly after being called by multipathd, regardless of whether the storage array responds. If the storage array hasn't responded, mulitpathd will check for a response every second, until checker_timeout seconds have elapsed.
Comment 6 Lin Li 2021-01-05 09:59:17 UTC 
Verified on device-mapper-multipath-0.8.4-7.el8
# rpm -qa | grep multipath
device-mapper-multipath-0.8.4-7.el8.ppc64le
device-mapper-multipath-libs-0.8.4-7.el8.ppc64le

# man multipath.conf
      checker_timeout  Specify the timeout to use for path checkers and  pri-
                        oritizers,  in  seconds.  Only prioritizers that issue
                        scsi commands use checker_timeout. Checkers that  sup-
                        port  an  asynchronous  mode  (tur and directio), will
                        return  shortly  after  being  called  by  multipathd,
                        regardless  of  whether the storage array responds. If
                        the storage array hasn't  responded,  mulitpathd  will
                        check for a response every second, until checker_time-
                        out seconds have elapsed.

                        The default is: in /sys/block/sd<x>/device/timeout
Comment 9 errata-xmlrpc 2021-05-18 15:06:46 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (device-mapper-multipath bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2021:1685