1439403 – RAID TAKEOVER: When attempting to convert to raid10, is raid6_n_6 sufficient?

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Bug 1439403 - RAID TAKEOVER: When attempting to convert to raid10, is raid6_n_6 sufficient?

Summary: RAID TAKEOVER: When attempting to convert to raid10, is raid6_n_6 sufficient?

Keywords:
Status:	CLOSED ERRATA
Alias:	None
Product:	Red Hat Enterprise Linux 7
Classification:	Red Hat
Component:	lvm2
Sub Component:
Version:	7.4
Hardware:	x86_64
OS:	Linux
Priority:	unspecified
Severity:	low
Target Milestone:	rc
Target Release:	---
Assignee:	Heinz Mauelshagen
QA Contact:	cluster-qe@redhat.com
Docs Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+	depends on / blocked

Reported:	2017-04-05 23:02 UTC by Corey Marthaler
Modified:	2021-09-03 12:38 UTC (History)
CC List:	8 users (show)
Fixed In Version:	lvm2-2.02.171-2.el7
Doc Type:	If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed:	2017-08-01 21:52:19 UTC
Target Upstream Version:
Embargoed:

Attachments	(Terms of Use)

Links
System	ID	Private	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHBA-2017:2222	0	normal	SHIPPED_LIVE	lvm2 bug fix and enhancement update	2017-08-01 18:42:41 UTC

Description Corey Marthaler 2017-04-05 23:02:00 UTC

Description of problem:
Feel free to close this if this is the expected behavior.

[root@harding-03 ~]# lvcreate  --type raid4 -i 3 -n LV -L 500M VG
  Using default stripesize 64.00 KiB.
  Rounding size 500.00 MiB (125 extents) up to stripe boundary size 504.00 MiB(126 extents).
  Logical volume "LV" created.

[root@harding-03 ~]# lvconvert --yes --type raid10 VG/LV
  Using default stripesize 64.00 KiB.
  Replaced LV type raid10 with possible type raid6_n_6.
  Logical volume VG/LV successfully converted.


Version-Release number of selected component (if applicable):
3.10.0-643.el7.x86_64

lvm2-2.02.169-3.el7    BUILT: Wed Mar 29 09:17:46 CDT 2017
lvm2-libs-2.02.169-3.el7    BUILT: Wed Mar 29 09:17:46 CDT 2017
lvm2-cluster-2.02.169-3.el7    BUILT: Wed Mar 29 09:17:46 CDT 2017
device-mapper-1.02.138-3.el7    BUILT: Wed Mar 29 09:17:46 CDT 2017
device-mapper-libs-1.02.138-3.el7    BUILT: Wed Mar 29 09:17:46 CDT 2017
device-mapper-event-1.02.138-3.el7    BUILT: Wed Mar 29 09:17:46 CDT 2017
device-mapper-event-libs-1.02.138-3.el7    BUILT: Wed Mar 29 09:17:46 CDT 2017
device-mapper-persistent-data-0.7.0-0.1.rc6.el7    BUILT: Mon Mar 27 10:15:46 CDT 2017

Comment 2 Corey Marthaler 2017-04-05 23:11:08 UTC

# Already at 6_n_6
[root@harding-03 ~]# lvconvert --yes --type raid10 VG/LV
  Using default stripesize 64.00 KiB.
  Unable to convert LV VG/LV from raid6_n_6 to raid10.
  Converting VG/LV from raid6_n_6 is directly possible to the following layouts:
    raid0
    raid0_meta
    striped
    raid4
    raid5_n
    raid6_nc
    raid6_nr
    raid6_zr
    raid6_la_6
    raid6_ls_6
    raid6_ra_6
    raid6_rs_6
[root@harding-03 ~]# lvconvert --yes --type raid0 VG/LV
  Using default stripesize 64.00 KiB.
  Logical volume VG/LV successfully converted.
[root@harding-03 ~]# lvconvert --yes --type raid10 VG/LV
  Using default stripesize 64.00 KiB.
  Logical volume VG/LV successfully converted.

Comment 3 Heinz Mauelshagen 2017-04-06 19:54:19 UTC

Replacing a raid10 request with raid6 is an error.
Command should fail and list the possible types.

Comment 6 Corey Marthaler 2017-05-26 22:21:12 UTC

From comment #3:
"Replacing a raid10 request with raid6 is an error.
Command should fail and list the possible types."


[root@host-126 ~]# lvcreate  --type raid4 -i 3 -n LV -L 500M VG
  Using default stripesize 64.00 KiB.
  Rounding size 500.00 MiB (125 extents) up to stripe boundary size 504.00 MiB(126 extents).
  Logical volume "LV" created.
[root@host-126 ~]# lvs -a -o +devices,segtype
  LV            VG  Attr       LSize   Cpy%Sync Devices                                                     Type  
  LV            VG  rwi-a-r--- 504.00m 100.00   LV_rimage_0(0),LV_rimage_1(0),LV_rimage_2(0),LV_rimage_3(0) raid4 
  [LV_rimage_0] VG  iwi-aor--- 168.00m          /dev/sda1(1)                                                linear
  [LV_rimage_1] VG  iwi-aor--- 168.00m          /dev/sdb1(1)                                                linear
  [LV_rimage_2] VG  iwi-aor--- 168.00m          /dev/sdc1(1)                                                linear
  [LV_rimage_3] VG  iwi-aor--- 168.00m          /dev/sdd1(1)                                                linear
  [LV_rmeta_0]  VG  ewi-aor---   4.00m          /dev/sda1(0)                                                linear
  [LV_rmeta_1]  VG  ewi-aor---   4.00m          /dev/sdb1(0)                                                linear
  [LV_rmeta_2]  VG  ewi-aor---   4.00m          /dev/sdc1(0)                                                linear
  [LV_rmeta_3]  VG  ewi-aor---   4.00m          /dev/sdd1(0)                                                linear

[root@host-126 ~]# lvconvert --yes --type raid10 VG/LV
  Using default stripesize 64.00 KiB.
  Replaced LV type raid10 (same as raid10_near) with possible type raid5_n.
  Repeat this command to convert to raid10 after an interim conversion has finished.
  Converting raid4 LV VG/LV to raid5_n.
  Logical volume VG/LV successfully converted.

[root@host-126 ~]# lvs -a -o +devices,segtype
  LV            VG  Attr       LSize   Cpy%Sync Devices                                                     Type   
  LV            VG  rwi-a-r--- 504.00m 100.00   LV_rimage_0(0),LV_rimage_1(0),LV_rimage_2(0),LV_rimage_3(0) raid5_n
  [LV_rimage_0] VG  iwi-aor--- 172.00m          /dev/sda1(1)                                                linear 
  [LV_rimage_1] VG  iwi-aor--- 172.00m          /dev/sdb1(1)                                                linear 
  [LV_rimage_2] VG  iwi-aor--- 172.00m          /dev/sdc1(1)                                                linear 
  [LV_rimage_3] VG  iwi-aor--- 172.00m          /dev/sdd1(1)                                                linear 
  [LV_rmeta_0]  VG  ewi-aor---   4.00m          /dev/sda1(0)                                                linear 
  [LV_rmeta_1]  VG  ewi-aor---   4.00m          /dev/sdb1(0)                                                linear 
  [LV_rmeta_2]  VG  ewi-aor---   4.00m          /dev/sdc1(0)                                                linear 
  [LV_rmeta_3]  VG  ewi-aor---   4.00m          /dev/sdd1(0)                                                linear

Comment 7 Heinz Mauelshagen 2017-05-31 13:21:45 UTC

(In reply to Corey Marthaler from comment #6)
> From comment #3:
> "Replacing a raid10 request with raid6 is an error.
> Command should fail and list the possible types."
> 
> 
> [root@host-126 ~]# lvcreate  --type raid4 -i 3 -n LV -L 500M VG
>   Using default stripesize 64.00 KiB.
>   Rounding size 500.00 MiB (125 extents) up to stripe boundary size 504.00
> MiB(126 extents).
>   Logical volume "LV" created.
> [root@host-126 ~]# lvs -a -o +devices,segtype
>   LV            VG  Attr       LSize   Cpy%Sync Devices                     
> Type  
>   LV            VG  rwi-a-r--- 504.00m 100.00  
> LV_rimage_0(0),LV_rimage_1(0),LV_rimage_2(0),LV_rimage_3(0) raid4 
>   [LV_rimage_0] VG  iwi-aor--- 168.00m          /dev/sda1(1)                
> linear
>   [LV_rimage_1] VG  iwi-aor--- 168.00m          /dev/sdb1(1)                
> linear
>   [LV_rimage_2] VG  iwi-aor--- 168.00m          /dev/sdc1(1)                
> linear
>   [LV_rimage_3] VG  iwi-aor--- 168.00m          /dev/sdd1(1)                
> linear
>   [LV_rmeta_0]  VG  ewi-aor---   4.00m          /dev/sda1(0)                
> linear
>   [LV_rmeta_1]  VG  ewi-aor---   4.00m          /dev/sdb1(0)                
> linear
>   [LV_rmeta_2]  VG  ewi-aor---   4.00m          /dev/sdc1(0)                
> linear
>   [LV_rmeta_3]  VG  ewi-aor---   4.00m          /dev/sdd1(0)                
> linear
> 
> [root@host-126 ~]# lvconvert --yes --type raid10 VG/LV
>   Using default stripesize 64.00 KiB.
>   Replaced LV type raid10 (same as raid10_near) with possible type raid5_n.
>   Repeat this command to convert to raid10 after an interim conversion has
> finished.
>   Converting raid4 LV VG/LV to raid5_n.
>   Logical volume VG/LV successfully converted.
> 
> [root@host-126 ~]# lvs -a -o +devices,segtype
>   LV            VG  Attr       LSize   Cpy%Sync Devices                     
> Type   
>   LV            VG  rwi-a-r--- 504.00m 100.00  
> LV_rimage_0(0),LV_rimage_1(0),LV_rimage_2(0),LV_rimage_3(0) raid5_n
>   [LV_rimage_0] VG  iwi-aor--- 172.00m          /dev/sda1(1)                
> linear 
>   [LV_rimage_1] VG  iwi-aor--- 172.00m          /dev/sdb1(1)                
> linear 
>   [LV_rimage_2] VG  iwi-aor--- 172.00m          /dev/sdc1(1)                
> linear 
>   [LV_rimage_3] VG  iwi-aor--- 172.00m          /dev/sdd1(1)                
> linear 
>   [LV_rmeta_0]  VG  ewi-aor---   4.00m          /dev/sda1(0)                
> linear 
>   [LV_rmeta_1]  VG  ewi-aor---   4.00m          /dev/sdb1(0)                
> linear 
>   [LV_rmeta_2]  VG  ewi-aor---   4.00m          /dev/sdc1(0)                
> linear 
>   [LV_rmeta_3]  VG  ewi-aor---   4.00m          /dev/sdd1(0)                
> linear

Corey,

converting from raid4 to raid involves raid4 -> raid5_n -> raid0_meta -> raid10(_near), i.e. a 3 step conversion process.
Hence the new code replaces the LV type with the next possible one raid5_n in this examples)and asks the user to repeat the initial command
("lvconvert --yes --type raid10 VG/LV" in this case).
So the functionality goes beyond what I stated and you copies in comment #6.

Please reevaluate and perfrom the multi-step conversions.

Comment 9 Corey Marthaler 2017-06-22 22:43:56 UTC

Marking verified based on new expectations listed in comment #7.

3.10.0-685.el7.x86_64
lvm2-2.02.171-7.el7    BUILT: Thu Jun 22 08:35:15 CDT 2017
lvm2-libs-2.02.171-7.el7    BUILT: Thu Jun 22 08:35:15 CDT 2017
lvm2-cluster-2.02.171-7.el7    BUILT: Thu Jun 22 08:35:15 CDT 2017
device-mapper-1.02.140-7.el7    BUILT: Thu Jun 22 08:35:15 CDT 2017
device-mapper-libs-1.02.140-7.el7    BUILT: Thu Jun 22 08:35:15 CDT 2017
device-mapper-event-1.02.140-7.el7    BUILT: Thu Jun 22 08:35:15 CDT 2017
device-mapper-event-libs-1.02.140-7.el7    BUILT: Thu Jun 22 08:35:15 CDT 2017
device-mapper-persistent-data-0.7.0-0.1.rc6.el7    BUILT: Mon Mar 27 10:15:46 CDT 2017



[root@host-092 ~]# lvcreate  --type raid4 -i 3 -n LV -L 500M VG
  Using default stripesize 64.00 KiB.
  Rounding size 500.00 MiB (125 extents) up to stripe boundary size 504.00 MiB(126 extents).         
  Logical volume "LV" created.
  
[root@host-092 ~]#  lvs -a -o +devices
  LV            VG  Attr       LSize   Cpy%Sync Devices                                              
  LV            VG  rwi-a-r--- 504.00m 100.00   LV_rimage_0(0),LV_rimage_1(0),LV_rimage_2(0),LV_rimage_3(0)
  [LV_rimage_0] VG  iwi-aor--- 168.00m          /dev/sda1(1)                                         
  [LV_rimage_1] VG  iwi-aor--- 168.00m          /dev/sdb1(1)                                         
  [LV_rimage_2] VG  iwi-aor--- 168.00m          /dev/sdc1(1)                                         
  [LV_rimage_3] VG  iwi-aor--- 168.00m          /dev/sdd1(1)                                         
  [LV_rmeta_0]  VG  ewi-aor---   4.00m          /dev/sda1(0)                                         
  [LV_rmeta_1]  VG  ewi-aor---   4.00m          /dev/sdb1(0)                                         
  [LV_rmeta_2]  VG  ewi-aor---   4.00m          /dev/sdc1(0)
  [LV_rmeta_3]  VG  ewi-aor---   4.00m          /dev/sdd1(0)
  
[root@host-092 ~]# lvconvert --yes --type raid10 VG/LV
  Using default stripesize 64.00 KiB. 
  Replaced LV type raid10 (same as raid10_near) with possible type raid0_meta.
  Repeat this command to convert to raid10 after an interim conversion has finished.
  Logical volume VG/LV successfully converted.
  
[root@host-092 ~]# lvconvert --yes --type raid10 VG/LV
  Using default stripesize 64.00 KiB. 
  Logical volume VG/LV successfully converted.
  
[root@host-092 ~]# lvs -a -o +devices,segtype
  LV            VG  Attr       LSize   Cpy%Sync Devices                                                                                   Type
  LV            VG  rwi-a-r--- 504.00m 100.00   LV_rimage_0(0),LV_rimage_3(0),LV_rimage_1(0),LV_rimage_4(0),LV_rimage_2(0),LV_rimage_5(0) raid10
  [LV_rimage_0] VG  iwi-aor--- 168.00m          /dev/sdb1(1)                                                                              linear
  [LV_rimage_1] VG  iwi-aor--- 168.00m          /dev/sdc1(1)                                                                              linear
  [LV_rimage_2] VG  iwi-aor--- 168.00m          /dev/sdd1(1)                                                                              linear
  [LV_rimage_3] VG  iwi-aor--- 168.00m          /dev/sda1(1)                                                                              linear
  [LV_rimage_4] VG  iwi-aor--- 168.00m          /dev/sde1(1)                                                                              linear
  [LV_rimage_5] VG  iwi-aor--- 168.00m          /dev/sdf1(1)                                                                              linear
  [LV_rmeta_0]  VG  ewi-aor---   4.00m          /dev/sdb1(0)                                                                              linear
  [LV_rmeta_1]  VG  ewi-aor---   4.00m          /dev/sdc1(0)                                                                              linear
  [LV_rmeta_2]  VG  ewi-aor---   4.00m          /dev/sdd1(0)                                                                              linear
  [LV_rmeta_3]  VG  ewi-aor---   4.00m          /dev/sda1(0)                                                                              linear
  [LV_rmeta_4]  VG  ewi-aor---   4.00m          /dev/sde1(0)                                                                              linear
  [LV_rmeta_5]  VG  ewi-aor---   4.00m          /dev/sdf1(0)                                                                              linear

Comment 10 errata-xmlrpc 2017-08-01 21:52:19 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, 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-2017:2222

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