1979470 – find_multipaths_timeout is overwritten by mpatchconf command

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Bug 1979470 - find_multipaths_timeout is overwritten by mpatchconf command

Summary: find_multipaths_timeout is overwritten by mpatchconf command

Keywords:
Status:	CLOSED ERRATA
Alias:	None
Product:	Red Hat Enterprise Linux 8
Classification:	Red Hat
Component:	device-mapper-multipath
Sub Component:
Version:	8.4
Hardware:	All
OS:	Linux
Priority:	low
Severity:	low
Target Milestone:	rc
Target Release:	---
Assignee:	Ben Marzinski
QA Contact:	Lin Li
Docs Contact:
URL:
Whiteboard:
Depends On:
Blocks:	1981594
TreeView+	depends on / blocked

Reported:	2021-07-06 07:07 UTC by Renaud Métrich
Modified:	2024-10-01 18:54 UTC (History)
CC List:	8 users (show)
Fixed In Version:	device-mapper-multipath-0.8.4-14.el8
Doc Type:	Bug Fix
Doc Text:	Cause: mpathconf wasn't correctly checking that there was one or more spaces between paramter names and their values, leading it to treat the find_multipaths_timeout parameter the same as find_multipaths parameter Consequence: If find_multipaths_timeout was set, and mpathconf was used to modify find_multipaths, it would convert the find_multipaths_timeout line into an invalid line. Fix: When mpathconf checks the existing multipath.conf file for parameters, it requires there to be one or more spaces between the parameter name and value Result: mpathconf no longer converts find_multipaths_timeout lines into invalid lines when updating the find_multipaths parameter.
Clone Of:
Clones:	1981594 (view as bug list)
Environment:
Last Closed:	2021-11-09 19:32:00 UTC
Type:	Bug
Target Upstream Version:
Embargoed:
Dependent Products:
Flags:	pm-rhel: mirror+

Attachments	(Terms of Use)

Links
System	ID	Private	Priority	Status	Summary	Last Updated
Red Hat Knowledge Base (Solution)	6169792	0	None	None	None	2021-07-06 15:40:08 UTC
Red Hat Product Errata	RHBA-2021:4367	0	None	None	None	2021-11-09 19:32:15 UTC

Description Renaud Métrich 2021-07-06 07:07:59 UTC

Description of problem:

When specifying find_multipaths_timeout in /etc/multipath.conf and executing mpatchconf --enable to change the find_multipaths mode, the find_multipaths_timeout property is overwritten, as shown below:

Original /etc/multipath.conf:
-------- 8< ---------------- 8< ---------------- 8< ---------------- 8< --------
defaults {
	user_friendly_names yes
	find_multipaths yes
	find_multipaths_timeout 10
	enable_foreign "^$"
}
[...]
-------- 8< ---------------- 8< ---------------- 8< ---------------- 8< --------

Execute mpathconf:
-------- 8< ---------------- 8< ---------------- 8< ---------------- 8< --------
# mpathconf --enable --with_multipathd y --find_multipaths strict
-------- 8< ---------------- 8< ---------------- 8< ---------------- 8< --------

Final result:
-------- 8< ---------------- 8< ---------------- 8< ---------------- 8< --------
defaults {
	user_friendly_names yes
	find_multipaths strict
	find_multipaths strict 10
	enable_foreign "^$"
}
[...]
-------- 8< ---------------- 8< ---------------- 8< ---------------- 8< --------


Version-Release number of selected component (if applicable):

device-mapper-multipath-0.8.4-10.el8.x86_64

How reproducible:

Always, see above.

Comment 1 Nitin U. Yewale 2021-07-06 13:31:46 UTC

Hi,

Following patch looks to be fixing the issue :

# cat mpathconf.patch 
--- /root/mpathconf.original	2021-07-06 18:40:15.514540136 +0530
+++ /usr/sbin/mpathconf	2021-07-06 18:44:36.757131720 +0530
@@ -331,7 +331,7 @@
 fi
 
 if [ "$HAVE_DEFAULTS" = "1" ]; then
-	HAVE_FIND=`sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | sed -n 's/^[[:blank:]]*find_multipaths[[:blank:]]*\([^[:blank:]]*\).*$/\1/p' | sed -n 1p`
+	HAVE_FIND=`sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | sed -n 's/^[[:blank:]]*find_multipaths[[:blank:]]\([^[:blank:]]*\).*$/\1/p' | sed -n 1p`
 	if [ "$HAVE_FIND" = "1" ]; then
 		HAVE_FIND="yes"
 	elif [ "$HAVE_FIND" = "0" ]; then
@@ -467,7 +467,7 @@
 ' $TMPFILE
 		CHANGED_CONFIG=1
 	elif [ "$FIND" != "$HAVE_FIND" ]; then
-		sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:blank:]]*find_multipaths[[:blank:]]*[^[:blank:]]*/	find_multipaths '"$FIND"'/' $TMPFILE
+		sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:blank:]]*find_multipaths[[:blank:]][^[:blank:]]*/	find_multipaths '"$FIND"'/' $TMPFILE
 		CHANGED_CONFIG=1
 	fi
 fi
[root@test1 tmp]# 

Thank you,
Nitin Yewale

Comment 2 Nitin U. Yewale 2021-07-06 13:34:46 UTC

Hi,

Tested following scenarios

[root@test1 ~]# cat /etc/multipath.conf

defaults {
	user_friendly_names yes
	find_multipaths no
	find_multipaths_timeout 10
	enable_foreign "^$"
}

After change :mpathconf --enable --with_multipathd y --find_multipaths strict

[root@test1 ~]# cat /etc/multipath.conf


defaults {
	user_friendly_names yes
	find_multipaths strict
	find_multipaths_timeout 10
	enable_foreign "^$"
}

[root@test1 ~]# 


=========================================================================================

[root@test1 ~]# cat /etc/multipath.conf

defaults {
	user_friendly_names yes
	find_multipaths_timeout 10
	enable_foreign "^$"
}

After change : mpathconf --enable --with_multipathd y --find_multipaths yes

[root@test1 ~]# cat /etc/multipath.conf

defaults {
	find_multipaths yes
	user_friendly_names yes
	find_multipaths_timeout 10
	enable_foreign "^$"
}


[root@test1 ~]# 


=========================================================================================

[root@test1 ~]# cat /etc/multipath.conf

defaults {
	user_friendly_names yes
	find_multipaths yes
	find_multipaths_timeout 10
	enable_foreign "^$"
}

After change : mpathconf --enable --with_multipathd y --find_multipaths strict

[root@test1 ~]# cat /etc/multipath.conf

defaults {
	user_friendly_names yes
	find_multipaths strict
	find_multipaths_timeout 10
	enable_foreign "^$"
}

[root@test1 ~]# 

=========================================================================================

[root@test1 ~]# cat /etc/multipath.conf

defaults {
	user_friendly_names yes
	enable_foreign "^$"
}

After change : mpathconf --enable --with_multipathd y --find_multipaths strict

[root@test1 ~]# cat /etc/multipath.conf

defaults {
	find_multipaths strict
	user_friendly_names yes
	enable_foreign "^$"
}

[root@test1 ~]# 


Thank you,
Nitin Yewale

Comment 4 Ben Marzinski 2021-07-08 21:59:54 UTC

Thanks for pointing this out. However, mpathconf should be able to handle lines like

find_multipaths    yes

where there are multiple spaces, so I plan to go with this instead:

# git diff
diff --git a/multipath/mpathconf b/multipath/mpathconf
index 2f4f3eaf..58077077 100644
--- a/multipath/mpathconf
+++ b/multipath/mpathconf
@@ -331,7 +331,7 @@ if [ "$HAVE_BLACKLIST" = "1" ]; then
 fi
 
 if [ "$HAVE_DEFAULTS" = "1" ]; then
-       HAVE_FIND=`sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | sed -n 's/^[[:blank:]]*find_multipaths[[:blank:]]*\([^[:blank:]]*\).*$/\1/p' | sed -n 1p`
+       HAVE_FIND=`sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | sed -n 's/^[[:blank:]]*find_multipaths[[:blank:]][[:blank:]]*\([^[:blank:]]*\).*$/\1/p' | sed -n 1p`
        if [ "$HAVE_FIND" = "1" ]; then
                HAVE_FIND="yes"
        elif [ "$HAVE_FIND" = "0" ]; then
@@ -467,7 +467,7 @@ if [ -n "$FIND" ]; then
 ' $TMPFILE
                CHANGED_CONFIG=1
        elif [ "$FIND" != "$HAVE_FIND" ]; then
-               sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:blank:]]*find_multipaths[[:blank:]]*[^[:blank:]]*/  find_multipaths '"$FIND"'/' $TMPFILE
+               sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:blank:]]*find_multipaths[[:blank:]][[:blank:]]*[^[:blank:]]*/       find_multipaths '"$FIND"'/' $TMPFILE
                CHANGED_CONFIG=1
        fi
 fi

Comment 5 Renaud Métrich 2021-07-09 07:05:56 UTC

Actually what would be even greater is to have mpathconf command handle this "find_multipaths_timeout" property.

Comment 7 Ben Marzinski 2021-07-09 20:00:56 UTC

The idea of mpathconf is to give the users the ability to change a few, commonly changed parameters. They are currently all ones where Red Hat has (or had) different defaults than upstream. I've considered giving mpathconf the ability to add any parameter to any section of multipath.conf, and you're welcome to file an RFE for that, but I'd like to just use this bugzilla to deal with the actual bug (and related space issues for the other parameters).

Comment 10 Ben Marzinski 2021-07-12 21:27:44 UTC

There were actually multiple places where mpathconf wasn't checking that existing parameters had one or more spaces between the parameter name and value. These have all been fixed.

Comment 14 Lin Li 2021-07-15 07:08:58 UTC

Reproduced on device-mapper-multipath-0.8.4-13.el8
1,[root@ibm-p9z-20-lp13 ~]# rpm -qa | grep multipath
device-mapper-multipath-libs-0.8.4-13.el8.ppc64le
device-mapper-multipath-0.8.4-13.el8.ppc64le

2,Edit /etc/multipath.conf 
[root@ibm-p9z-20-lp13 ~]# cat /etc/multipath.conf 
defaults {
    user_friendly_names yes
    find_multipaths yes
    find_multipaths_timeout 10
    enable_foreign "^$"
}

3,[root@ibm-p9z-20-lp13 ~]# mpathconf --enable --with_multipathd y --find_multipaths strict

4,check /etc/multipath.conf 
[root@ibm-p9z-20-lp13 ~]# cat /etc/multipath.conf 
defaults {
    user_friendly_names yes
	find_multipaths strict
	find_multipaths strict 10   <----------------------find_multipaths_timeout is overwritten
    enable_foreign "^$"
}


Verified on device-mapper-multipath-0.8.4-14.el8
1,[root@ibm-p9z-20-lp13 ~]# rpm -qa | grep multipath
device-mapper-multipath-libs-0.8.4-14.el8.ppc64le
device-mapper-multipath-0.8.4-14.el8.ppc64le
2,Edit /etc/multipath.conf 
[root@ibm-p9z-20-lp13 ~]# cat /etc/multipath.conf 
defaults {
    user_friendly_names yes
    find_multipaths yes
    find_multipaths_timeout 10
    enable_foreign "^$"
}

3,[root@ibm-p9z-20-lp13 ~]# mpathconf --enable --with_multipathd y --find_multipaths strict

4,check /etc/multipath.conf 
[root@ibm-p9z-20-lp13 ~]# cat /etc/multipath.conf 
defaults {
    user_friendly_names yes
    find_multipaths strict
    find_multipaths_timeout 10    <----------------------find_multipaths_timeout is not overwritten
    enable_foreign "^$"
}


Test result:When mpathconf checks the existing multipath.conf file for parameters, it requires there to be one or more spaces between the parameter name and value

Comment 18 errata-xmlrpc 2021-11-09 19:32:00 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/RHBA-2021:4367

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