vgchange: Too many links

[mjos]

Hi,
When I do a vgdisplay on one of the VGs, I am getting the below error -

vgdisplay -v /dev/vg_db01


The specified path does not correspond to physical volume attached to
this volume group
vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c92t2d5":
The specified path does not correspond to physical volume attached to
this volume group
vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c92t7d0":
The specified path does not correspond to physical volume attached to
this volume group
vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c96t2d4":
The specified path does not correspond to physical volume attached to
this volume group
vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c96t2d5":
The specified path does not correspond to physical volume attached to
this volume group
vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c96t7d0":
The specified path does not correspond to physical volume attached to
this volume group

--- Volume groups ---
VG Name /dev/adop_db01
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 9
Open LV 9
Max PV 16
Cur PV 3
Act PV 3
Max PE per PV 2047
VGDA 6
PE Size (Mbytes) 32
Total PE 4093
Alloc PE 4002
Free PE 91
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0



VG Name /dev/vg_db01

--- Physical volumes ---
PV Name /dev/dsk/c70t2d4
PV Name /dev/dsk/c74t2d4 Alternate Link
PV Name /dev/dsk/c94t2d4 Alternate Link
PV Name /dev/dsk/c98t2d4 Alternate Link
PV Name /dev/dsk/c118t2d4 Alternate Link
PV Name /dev/dsk/c122t2d4 Alternate Link
PV Name /dev/dsk/c142t2d4 Alternate Link
PV Name /dev/dsk/c146t2d4 Alternate Link
PV Status available
Total PE 2047
Free PE 0
Autoswitch On
Proactive Polling On

PV Name /dev/dsk/c70t2d5
PV Name /dev/dsk/c74t2d5 Alternate Link
PV Name /dev/dsk/c94t2d5 Alternate Link
PV Name /dev/dsk/c98t2d5 Alternate Link
PV Name /dev/dsk/c118t2d5 Alternate Link
PV Name /dev/dsk/c122t2d5 Alternate Link
PV Name /dev/dsk/c142t2d5 Alternate Link
PV Name /dev/dsk/c146t2d5 Alternate Link
PV Status available
Total PE 1023
Free PE 0
Autoswitch On
Proactive Polling On

PV Name /dev/dsk/c70t7d0
PV Name /dev/dsk/c74t7d0 Alternate Link
PV Name /dev/dsk/c94t7d0 Alternate Link
PV Name /dev/dsk/c98t7d0 Alternate Link
PV Name /dev/dsk/c118t7d0 Alternate Link
PV Name /dev/dsk/c122t7d0 Alternate Link
PV Name /dev/dsk/c142t7d0 Alternate Link
PV Name /dev/dsk/c146t7d0 Alternate Link
PV Status available
Total PE 1023
Free PE 91
Autoswitch On
Proactive Polling On

There are 16 alternate links & I need to add all of them into the VG, so that the above error doesnt show up. I recreated the lvmtab file after moving the /etc/lvmtab file & then did a vgscan & activated the VGs. Again I am getting the same error in vgdisplay.
In vgchange, also I am getting the below error.

# vgchange -a y /dev/adop_db01
vgchange: Warning: Couldn't attach to the volume group physical volume "/dev/dsk/c68t2d4":
Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
vgchange: Too many links
Volume group "/dev/adop_db01" has been successfully changed.

[mjos]

The VG characteristics are below

--- Volume groups ---
VG Name /dev/vg_db01
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 9
Open LV 9
Max PV 16
Cur PV 3
Act PV 3
Max PE per PV 2047
VGDA 6
PE Size (Mbytes) 32
Total PE 4093
Alloc PE 4002
Free PE 91
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

OS version is B.11.23 U ia64

[Aneesh Mohan]

I belive prior to HPUX 11.31 ,only 8 links are possible to a disk.In 11.31 it is 32.

Aneesh

[Johnson Punniyalingam · Accepted solution]

Please follow official procedures

http://docs.hp.com/en/5991-1236/When_Good_Disks_Go_Bad_WP.pdf


ITRC member since: October 02, 2007
Last contribution date: November 17, 2009
I have assigned points to 54 of 223 responses to my questions.

The status does't look nice, assign points for the people who share the knowledge and time in suggestions in your problems

[mjos]

Thanks, in that case, how do I remove the too many links message. I did an ioscan for the disks & could not find any disk with no_hw.

[mjos]

Johnson, how did you get that status. As far as I remember, I submit points to most of the solutions that I recieve. I would like to check the stats myself.

[Johnson Punniyalingam]

follow the above "PDF" file

suspecting your /etc/lvmtab got some issue

[mjos]

Hi, I dont think any disk has gone bad over here. It is a question of adding more alternate links to an VG. Is there a limitation of 8 alternate links in 11.23?

[Johnson Punniyalingam]

>>Hi, I dont think any disk has gone bad over here. It is a question of adding more alternate links to an VG. Is there a limitation of 8 alternate links in 11.23?

You can specify physical volume links pv-links for a physical volume providing different paths that reference the same physical volume in the pv_path list. The order in which the paths are listed is important. The first path becomes the primary link to the physical volume, and the second becomes an alternate link to the physical volume. The primary link is the default path used to access the physical volume. (see WARNINGS section). If the primary link becomes unavailable, LVM automatically switches to the alternate link to access the physical volume. Currently, LVM supports a maximum of 8 paths to a physical volume (7 alternate and one primary).

[mjos]

Thanks, so that summarized it, only 7 alternate links can be added to the primary path in 11.23

[Aneesh Mohan]

Yes , that is what I have mentioned initially.

Aneesh

[mjos]

Ok, is there any way I can remove the links that doesnt show up in alternate links but shows up as error messages in the vgdisplay command

[Johnson Punniyalingam]

Ok, is there any way I can remove the links that doesnt show up in alternate links but shows up as error messages in the vgdisplay command

>>run vgremove vgname alternate path<<

[Aneesh Mohan]

Hi,

Just do

# vgreduce -f vg_db01

Aneesh

[Johnson Punniyalingam]

>>Ok, is there any way I can remove the links that doesnt show up in alternate links but shows up as error messages in the vgdisplay command

>>run vgremove vgname alternate path<<

Sorry !! Sorry !!wrong posting --> Apologies

vgreduce /dev/vg /dev/dsk/cxdxsx

[mjos]

thanks, there are lots of alternate paths, so I need to do this for each one of them. Is there any single command which will remove the alternate links which are not a part of the VG? The vgremove command can do this but the issue is I need to run this command for a large number of disks.

[mjos]

Ooops sorry not vgremove, it is vgreduce...

[mjos]

Aneesh, vgreduce -f doesn't work. The vgdispaly still shows up errors

# vgdisplay -v /dev/vg_db01

vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c68t2d6":
The specified path does not correspond to physical volume attached to
this volume group
vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c72t2d6":
The specified path does not correspond to physical volume attached to
this volume group
vgdisplay: Warning: couldn't query physical volume "/dev/dsk/c92t2d6":
The specified path does not correspond to physical volume attached to
this volume group
........
........

[Torsten.]

16 links to a LUN? What array is it?

Normally it doesn't make so much sense to configure so many links.

[mjos]

It is an HP EVA - 6110. I think the way the server was zoned to see the array, the lun presented to it ends up in 16 alternate links. But since it is 11.23, it is taking up only 7 alternate links to the primary path.

[Pete Randall]

> how did you get that status. As far as I remember, I submit points to most of the solutions that I recieve. I would like to check the stats myself.


Click on your userid to bring up your profile. This will show you the "I have assigned points to X of Y questions" stat.


Pete

[mjos]

Ya got that, the stats are not that bad though.

[Torsten.]

The EVA 6100 has 4 front ports, so I still wonder why you have so many pathes. How many HBAs do you have in that server?

[mjos]

There are four fc cards on the server

# ls fc*
fcd0 fcd2 fcd3 fcd4

[Torsten.]

Even with 4 HBAs you should "Only" see 8 pathes, not 16 - right? Maybe there is something wrong with your SAN config.