VxVM - VxDMP Confused
Thursday, March 27, 2008 at 2:58 PM | 0 comments
Today I got a call from one of my peers regarding a problem with missing LUNs.

The SAN team presented certain number of LUNs to his 3 AIX servers but all 3 had the same exact issue. All are missing 7 LUNs.

I helped out because I thought that this should be an easy one. First he told me he ran these 3 commands:
# cfgmgr
# vxdisk scandisks
# vxdctl enable


That should do it. He ran the right commands. But didn't work. So, I had to get in to the servers and look around. First, I saw some old disks from the old SHARK array which was already been disconnected. I cleared those up and re-ran those 3 commands. Still did not work.

Then, I counted all the hdisks on each HBA and compared with the hdisks listed in "vxdisk path" command. They matched. So, I thought that didn't make sense. So, I carefully reviewed the vxdisk path output and noticed that some of the devices have 4 paths and I counted 7 of those. There, I found out what the problem was. 4 paths to a LUN with only 2 HBAs active on the server. I have seen this on a Clariion but not on Symmetrix where these servers are connected to.

So, these are the steps I took to fix the problem:

1. Removed the hdisks on those 7 devices
2. Ran vxdisk scandisks ; vxdctl enable
3. Ran cfgmgr -vl fcs1 ; cfgmgr -vl fcs4
4. Ran vxdisk scandisks ; vxdctl enable

Now, how that happened, I don't know. Could be a bug in Veritas 4.0.

Here are the detailed steps:

# vxdmpadm listctlr all
CTLR-NAME       ENCLR-TYPE      STATE      ENCLR-NAME
=====================================================
scsi0           Disk            ENABLED      Disk
fscsi4          EMC             ENABLED      EMC0
fscsi1          EMC             ENABLED      EMC0
fscsi4          EMC             ENABLED      EMC1
fscsi1          EMC             ENABLED      EMC1

# lscfg | grep hdisk | grep EMC | cut -d"W" -f2 | cut -d"-" -f1 | sort -u
50060482CCB501C6
50060482CCB501C9
50060482CCAB5543
50060482CCAB554C

# lscfg | grep 50060482CCB501C6 | wc -l
      48

# lscfg | grep 50060482CCB501C9 | wc -l
      48

# lscfg | grep 50060482CCAB5543 | wc -l
      58

# lscfg | grep 50060482CCAB554C | wc -l
      58

# vxdisk list | grep EMC0 | wc -l
      48

# vxdisk list | grep EMC1 | wc -l
      51

# vxdisk list EMC1_19 | grep hdisk
hdisk97         state=enabled
hdisk107        state=enabled
hdisk211        state=enabled
hdisk182        state=enabled

# lscfg | egrep 'hdisk97|hdisk107|hdisk211|hdisk182'
* hdisk107         U5791.001.99205GR-P2-C10-T1-W50060482CCAB5543-L92000000000000  EMC Symmetrix FCP Raid5
* hdisk211         U5791.001.99205GR-P2-C10-T1-W50060482CCAB5543-LAD000000000000  EMC Symmetrix FCP Raid5
* hdisk97          U5791.001.99205LM-P2-C03-T1-W50060482CCAB554C-L92000000000000  EMC Symmetrix FCP Raid5
* hdisk182         U5791.001.99205LM-P2-C03-T1-W50060482CCAB554C-LAD000000000000  EMC Symmetrix FCP Raid5

# for i in 19 20 21 22 23 24 25
do
  vxdisk list EMC1_$i | grep hdisk | awk '{ print $1 }'
done | while read disk
do
  rmdev -dl $disk
done

# vxdisk scandisks ; vxdctl enable

# cfgmgr -vl fcs1; cfgmgr -vl fcs4

# vxdisk scandisks ; vxdctl enable

# vxdisk list | grep EMC1 | wc -l
      58

# vxdisk list EMC1_19 | grep hdisk
hdisk107        state=enabled
hdisk211        state=enabled
Posted by JAUGHN Labels:
AIX Index
at 9:52 AM | 0 comments
Here’s a collection of my AIX documents. Some were from my own work and some were taken from the web.

These documents were posted mainly for my personal references and for others that may find them useful.


Operating System

Tuning

Redbooks

Fixes, Tips and Tricks




Some Very Helpful Sites




Man Pages
Posted by JAUGHN Labels:
AIX - Switching Between 32bit and 64bit
at 9:22 AM | 0 comments
Before switching to 64bit mode, make sure the hardware supports it.

To verify what is running and what the hardware can support, run the following as root:
# echo "Hardware:\t`bootinfo -y` bits capable"
Hardware:       64 bits capable

# echo "Running:\t`bootinfo -K` bits mode"
Running:        32 bits mode

# ls -l /unix /usr/lib/boot/unix
lrwxrwxrwx 1 root  system  21 Aug 15 2006  /unix -> /usr/lib/boot/unix_mp
lrwxrwxrwx 1 root  system  21 Aug 15 2006  /usr/lib/boot/unix -> /usr/lib/boot/unix_mp


Switching From 32 to 64 Bit Mode

To switch from 32-bit mode to 64-bit mode run the following commands, in the given order:
1. ln -sf /usr/lib/boot/unix_64 /unix
2. ln -sf /usr/lib/boot/unix_64 /usr/lib/boot/unix
3. bosboot -ad /dev/ipldevice
4. shutdown -Fr


Switching From 64 To 32-Bit Mode

To switch from 64-bit mode to 32-bit mode run the following commands, in the given order:
1. ln -sf /usr/lib/boot/unix_mp /unix
2. ln -sf /usr/lib/boot/unix_mp /usr/lib/boot/unix
3. bosboot -ad /dev/ipldevice
4. shutdown -Fr
Posted by JAUGHN Labels:
Visit the Site
MARVEL and SPIDER-MAN: TM & 2007 Marvel Characters, Inc. Motion Picture © 2007 Columbia Pictures Industries, Inc. All Rights Reserved. 2007 Sony Pictures Digital Inc. All rights reserved. blogger template by blog forum