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Bug 1077773

Summary: XtremIO device can't be recognized when using "path_selector"
Product: Red Hat Enterprise Linux 7 Reporter: vincent_chen <vincent.y.chen>
Component: device-mapper-multipathAssignee: Ben Marzinski <bmarzins>
Status: CLOSED NOTABUG QA Contact: Red Hat Kernel QE team <kernel-qe>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 7.0CC: agk, bmarzins, heinzm, msnitzer, prajnoha
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2014-03-26 04:49:52 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Attachments:
Description Flags
multipath conf
none
multipath -v3 none

Description vincent_chen 2014-03-18 14:38:59 UTC
Description of problem:
Configure XtremIO device in multiapth.conf, the XIO device can't be congnized with "path_selector" attribute. if I remove "path_selector", the XIO device can't be detected.

Version-Release number of selected component (if applicable):
device-mapper-multipath-0.4.9-65.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1. add XtremIO device into multipath.conf
   device {
               vendor                  XtremIO
               product                 XtremApp
#               path_selector           "queue-length 0“
               path_selector           "round-robin 0“
#              path_selector           "service-time 0“
               rr_min_io               1
               path_grouping_policy    multibus
       }

2. restart multipath service
3.  check multipath device
      
Actual results:
XtremIO device can't seen with path_selector

Expected results:
XtremIO device  could be found

Additional info:
when restart multipath service, the log show 
===========  XtermIO device is multipathi =======
Mar 18 10:07:10 LXH8SER4 kernel: [15251.285803] device-mapper: table: 253:3: multipath: unknown path selector type
Mar 18 10:07:10 LXH8SER4 kernel: [15251.285811] device-mapper: ioctl: error adding target to table
Mar 18 10:07:10 LXH8SER4 multipathd: mpathi: removing map
Mar 18 10:07:10 LXH8SER4 kernel: device-mapper: table: 253:3: multipath: unknown path selector type
Mar 18 10:07:10 LXH8SER4 kernel: device-mapper: ioctl: error adding target to table
==================================================

[root@LXh8SER4 ~]# ls -l /dev/mapper/*
crw-------. 1 root root 10, 236 Mar 18 05:53 /dev/mapper/control
lrwxrwxrwx. 1 root root       7 Mar 18 10:12 /dev/mapper/mpathi -> ../dm-3

======================================
ls -l //dev/* 
....
lrwxrwxrwx. 1 root root 7 Mar 18 10:12 253:3 -> ../dm-3

Comment 2 Ben Marzinski 2014-03-18 15:02:11 UTC
That's odd.  Can you try manually loading the path selector modules.

# modprobe dm_service_time
# modprobe dm_round_robin
# modprobe dm_queue_length

Also, can you attach your /etc/multipath.conf and the whole output of

# multipath -v3

when it is failing to load the devices.

Comment 3 vincent_chen 2014-03-18 15:29:09 UTC
Created attachment 876007 [details]
multipath conf

Comment 4 vincent_chen 2014-03-18 15:30:12 UTC
Created attachment 876008 [details]
multipath -v3

Comment 5 vincent_chen 2014-03-18 15:30:41 UTC
mode load has no problem

lsmod |grep service_time
dm_service_time        12817  0
dm_multipath           22873  5 dm_round_robin,dm_queue_length,dm_service_time

Comment 6 vincent_chen 2014-03-25 08:20:14 UTC
any update on this issue?

Comment 7 Ben Marzinski 2014-03-26 04:49:52 UTC
Here is the hexdump of the relevant part of multipath.conf

00000a90  20 20 20 20 20 20 20 20  20 70 61 74 68 5f 73 65  |         path_se|
00000aa0  6c 65 63 74 6f 72 20 20  20 20 20 20 20 20 20 20  |lector          |
00000ab0  20 22 71 75 65 75 65 2d  6c 65 6e 67 74 68 20 30  | "queue-length 0|
00000ac0  e2 80 9c 0a 20 20 20 20  20 20 20 20 20 20 20 20  |....            |
00000ad0  20 20 20 70 61 74 68 5f  73 65 6c 65 63 74 6f 72  |   path_selector|
00000ae0  20 20 20 20 20 20 20 20  20 20 20 22 72 6f 75 6e  |           "roun|
00000af0  64 2d 72 6f 62 69 6e 20  30 e2 80 9c 0a 23 20 20  |d-robin 0....#  |
00000b00  20 20 20 20 20 20 20 20  20 20 20 20 20 70 61 74  |             pat|
00000b10  68 5f 73 65 6c 65 63 74  6f 72 20 20 20 20 20 20  |h_selector      |
00000b20  20 20 20 20 20 22 73 65  72 76 69 63 65 2d 74 69  |     "service-ti|
00000b30  6d 65 20 30 e2 80 9c 0a  20 20 20 20 20 20 20 20  |me 0....        |

The closing double quotes are not ascii double quotes.  They are, I believe UTF-8 double backquotes.  The multipath.conf file must be in all ascii.