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How to rename Agile View Device Special Files for HP-UX 11i v3 Service Guard Environment

Abstract

The following articles explains how to rename disk Agile View Device Special Files for HP-UX 11i v3 Service Guard environment. The introduction of Agile Addressing on HP-UX 11.31 adds new challenges to the old problem of keeping the device special files naming in-sync between ServiceGuard nodes. The co-existence of Agile and Legacy device special files adds a new layer to the problem.

Agile Device Special file name is tighly based on the Device Instance number assigned to the Agile Device H/W Path. That situation mades keeping devices naming in sync on a Service Guard environment somewhat more complex that in the past.

Contents


Introduction to Agile and Legacy Device Special File instance numbering

On HP-UX 11i v3 by default, two naming conventions coexists for the disk device class: Agile and Legacy Views.

Legacy

# ioscan -fnkC disk
Class     I  H/W Path       Driver S/W State   H/W Type     Description
=======================================================================
disk      5  0/0/3/0.0.0.0  sdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                           /dev/dsk/c0t0d0   /dev/rdsk/c0t0d0
disk      0  0/1/1/0.1.0    sdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                           /dev/dsk/c2t1d0   /dev/rdsk/c2t1d0
disk      1  0/1/1/0.8.0    sdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                           /dev/dsk/c2t8d0   /dev/rdsk/c2t8d0
disk      2  0/1/1/0.10.0   sdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                           /dev/dsk/c2t10d0   /dev/rdsk/c2t10d0
disk      3  0/1/1/0.12.0   sdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                           /dev/dsk/c2t12d0   /dev/rdsk/c2t12d0
disk      4  0/1/1/1.0.0    sdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                           /dev/dsk/c3t0d0   /dev/rdsk/c3t0d0

Agile

# ioscan -fnkNC disk
Class     I  H/W Path  Driver S/W State   H/W Type     Description
===================================================================
disk      6  64000/0xfa00/0x0  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk6   /dev/rdisk/disk6
disk      7  64000/0xfa00/0x1  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk7   /dev/rdisk/disk7
disk      9  64000/0xfa00/0x2  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk9   /dev/rdisk/disk9
disk      8  64000/0xfa00/0x3  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk8   /dev/rdisk/disk8
disk     10  64000/0xfa00/0x4  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk10   /dev/rdisk/disk10
disk     11  64000/0xfa00/0x5  esdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                      /dev/disk/disk11   /dev/rdisk/disk11

Agile to Legacy Device Mapping

# ioscan -m dsf
Persistent DSF           Legacy DSF(s)
========================================
/dev/rdisk/disk6         /dev/rdsk/c2t1d0
/dev/rdisk/disk7         /dev/rdsk/c2t8d0
/dev/rdisk/disk8         /dev/rdsk/c2t10d0
/dev/rdisk/disk9         /dev/rdsk/c2t12d0
/dev/rdisk/disk10        /dev/rdsk/c3t0d0
/dev/rdisk/disk11        /dev/rdsk/c0t0d0


  1. Legacy device instance (I) number assignment has precedence over Agile. At system cold-install, the Legacy devices will get assigned the lower instance numbers while the Agile devices will start from the last legacy instance.
  2. The Agile device name is based on the instance number assigned. This mean that /dev/disk/diskn will have the n instance number.
  3. Adding additional disk devices, will assigned new instance number to the Legacy devices first and to the Agile devices second.
  4. Co-existence of both naming schemes is required for backward compatibility with HP-UX releases prior to 11i v3, mainly to support Upgrade-UX.

Due to this fact, is very common when managing large SAN deployments, where each disk has several Legacy Device Special Files associated according to the number of paths, that the Instance Number asigned to the Agile devices reach into the hundreds.

In strict sense, Logical Volume Manager and VxVM handle their respectively Physical Volumes or Disks based on metadata headers place on the actual LUNs, so ther is no technical requirement for the Device Special Files to share the device special file name across the different nodes.

The drawback of keeping different names across the nodes is the added complexity to device identification and day to day management.

Configuration Best Practices

These best practices applies for new installations, were there is no need to keep Legacy Addressing in place. On systems upgraded using Update-UX, migrating the LVM volume group or VxVM diskgroup configuration to Agile Addressing is a prerequiste to Agile Device renumbering.

  1. Install HP-UX 11i v3 only with the minimal required storage attach to it: a single internal boot disk and DVD.
  2. Disable Legacy View immediately after system installation and before adding any additional storage.
  3. Restrict adding new storage, like JBODS or SAN Luns one device or source at a time.
  4. Use ioinit command to maintain the desired naming scheme. Is common practice, to reserve the first ten (0-15) instance numbers to the system internal or boot devices and those above for external storage device special files. Another common layout is numbering the storage SAN storage devices starting from instance 100.

Day One Agile Device Renaming

The following example explains the execution of this previous best practices after installing the HP-UX 11i v3 Operating System in a system using Logical Volume Manage (LVM).

The external storage was connect at the of the Operating System installation to add additional complexity, that is a common scenario and will allow the opportunity to show to change the instance numbers operates on more than a couple of devices.

Check again the previous output for the system. This server (rp4440) has one internal DVD, two internal drives and three external disks on a DS2100 (JBOD). The Legacy devices occupy instances 0 to 5 while the Agile occupy instances 6 to 11.

The objective is to remove the Legacy devices and renumber the agile devices beginning from instance 0.

After this change has been done, additional information is provided in how to move the device special file to higher numbers.

Disable Legacy View

1. Confirm that no other volume group besides /dev/vg00 are on the system. On new installation when the previous guidelines were followed, that will be the case, but this procedure may be adapted to re-layout a more complex deployment.

LVM and VxVM volume group export or deport procedure can be follow to move the volumes to the new disk schemes. Currently, only LVM is shown in this article.

For example:

# strings /etc/lvmtab | grep dev
/dev/vg00
/dev/disk/disk6

# strings /etc/lvmtab_p | grep dev

Take note that the current boot physical volume in this sysgtem configuration is /dev/disk/disk6.


2. Use rmf -L command to remove all the legacy devices.

# rmsf -L
         WARNING: This command may be disruptive to the system.
         Before running this command, make sure you have first run
         iofind(1M) and migrated all applications using legacy device
         special files. Please refer to the man page of rmsf(1M) to
         verify the possible side effects of the option '-L'.
         Do you want to continue ?
         (You must respond with 'y' or 'n'.): y
rmsf: Legacy mode has been successfully disabled


3. Confirm that Legacy device special files has been disable.

 # ioscan -fnkC disk

Note that no output should be displayed.


4. Check the Agile Device special files.

# ioscan -NfnkC disk
Class     I  H/W Path  Driver S/W State   H/W Type     Description
===================================================================
disk      6  64000/0xfa00/0x0  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk6   /dev/rdisk/disk6
disk      7  64000/0xfa00/0x1  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk7   /dev/rdisk/disk7
disk      9  64000/0xfa00/0x2  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk9   /dev/rdisk/disk9
disk      8  64000/0xfa00/0x3  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk8   /dev/rdisk/disk8
disk     10  64000/0xfa00/0x4  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk10   /dev/rdisk/disk10
disk     11  64000/0xfa00/0x5  esdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                      /dev/disk/disk11   /dev/rdisk/disk11

5. Use the ioinit -rC disk to reorder the instance number. This will reboot the system.


6. Boot in LVM Maintenance Mode.


7. In LVM Maintenance Mode, verify that the changes were done to the instance numbers.

# ioscan -NfnkC disk
Class     I  H/W Path  Driver S/W State   H/W Type     Description
===================================================================
disk      0  64000/0xfa00/0x0  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk6   /dev/rdisk/disk6
disk      1  64000/0xfa00/0x1  esdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                      /dev/disk/disk7   /dev/rdisk/disk7
disk      2  64000/0xfa00/0x2  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk8   /dev/rdisk/disk8
disk      3  64000/0xfa00/0x3  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk9   /dev/rdisk/disk9
disk      4  64000/0xfa00/0x4  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk10   /dev/rdisk/disk10
disk      5  64000/0xfa00/0x5  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk11   /dev/rdisk/disk11

Note that while the instance numbers has been reordered, the device special files still points to the former device special files.


8. Recreate the device special files using insf -e.

# insf -e
insf: Installing special files for asio0 instance 0 address 0/0/1/0
insf: Installing special files for asio0 instance 1 address 0/0/1/1
insf: Installing special files for ipmi instance 0 address 16
insf: Installing special files for side instance 0 address 0/0/3/0.0
insf: Installing special files for side instance 1 address 0/0/3/0.1
insf: Installing special files for mpt instance 2 address 0/1/1/0
insf: Installing special files for mpt instance 3 address 0/1/1/1
insf: Installing special files for fcd instance 0 address 0/4/1/0/4/0
insf: Installing special files for esdisk instance 0 address 64000/0xfa00/0x0
insf: Installing special files for esdisk instance 1 address 64000/0xfa00/0x1
insf: Installing special files for esdisk instance 2 address 64000/0xfa00/0x2
insf: Installing special files for esdisk instance 3 address 64000/0xfa00/0x3
insf: Installing special files for esdisk instance 4 address 64000/0xfa00/0x4
insf: Installing special files for esdisk instance 5 address 64000/0xfa00/0x5
insf: Installing special files for pseudo driver cn
insf: Installing special files for pseudo driver arp
insf: Installing special files for pseudo driver mm
insf: Installing special files for pseudo driver devkrs
insf: Installing special files for pseudo driver ptym
insf: Installing special files for pseudo driver ptys
insf: Installing special files for pseudo driver iomem
insf: Installing special files for pseudo driver dmem
insf: Installing special files for pseudo driver diag0
insf: Installing special files for pseudo driver ip
insf: Installing special files for pseudo driver nuls
insf: Installing special files for pseudo driver rawip
insf: Installing special files for pseudo driver stcpmap
insf: Installing special files for pseudo driver dev_config
insf: Installing special files for pseudo driver strlog
insf: Installing special files for pseudo driver sad
insf: Installing special files for pseudo driver tcp
insf: Installing special files for pseudo driver telm
insf: Installing special files for pseudo driver tels
insf: Installing special files for pseudo driver tlclts
insf: Installing special files for pseudo driver tlcots
insf: Installing special files for pseudo driver tlcotsod
insf: Installing special files for pseudo driver udp
insf: Installing special files for pseudo driver asyncdsk
insf: Installing special files for pseudo driver echo
insf: Installing special files for pseudo driver dlpi
insf: Installing special files for pseudo driver ptm
insf: Installing special files for pseudo driver pts
insf: Installing special files for pseudo driver beep
insf: Installing special files for pseudo driver framebuf
insf: Installing special files for pseudo driver diag1
insf: Installing special files for pseudo driver klog
insf: Installing special files for pseudo driver sy
insf: Installing special files for pseudo driver kepd
insf: Installing special files for pseudo driver diag2
insf: Installing special files for pseudo driver root
insf: Installing special files for pseudo driver escsi
# ioscan -NfnkC disk
Class     I  H/W Path  Driver S/W State   H/W Type     Description
===================================================================
disk      0  64000/0xfa00/0x0  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk0   /dev/rdisk/disk0
                      /dev/disk/disk6   /dev/rdisk/disk6
disk      1  64000/0xfa00/0x1  esdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                      /dev/disk/disk1   /dev/rdisk/disk1
                      /dev/disk/disk7   /dev/rdisk/disk7
disk      2  64000/0xfa00/0x2  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk2   /dev/rdisk/disk2
                      /dev/disk/disk8   /dev/rdisk/disk8
disk      3  64000/0xfa00/0x3  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk3   /dev/rdisk/disk3
                      /dev/disk/disk9   /dev/rdisk/disk9
disk      4  64000/0xfa00/0x4  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk10   /dev/rdisk/disk10
                      /dev/disk/disk4    /dev/rdisk/disk4
disk      5  64000/0xfa00/0x5  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk11   /dev/rdisk/disk11
                      /dev/disk/disk5    /dev/rdisk/disk5

Note that two sets of device special files will be assigned to each physical volume.


9. Export /dev/vg00 and import back using the new device special file, /dev/disk/disk0 in this example:

# vgexport -p -s -m /vg00.map /dev/vg00
vgexport: Preview of vgexport on volume group "/dev/vg00" succeeded.

# cat /vg00.map
VGID 1e69dc324ad20b84
1 lvol1
2 lvol2
3 lvol3
4 lvol4
5 lvol5
6 lvol6
7 lvol7
8 lvol8
9 lvol9
11 lvlog

# vgexport /dev/vg00
vgexport: Volume group "/dev/vg00" has been successfully removed.

# mkdir -m 755 /dev/vg00

# mknod /dev/vg00/group c 64 0x000000

# vgimport -m /vg00.map /dev/vg00 /dev/disk/disk0
vgimport: Volume group "/dev/vg00" has been successfully created.
Warning: A backup of this volume group may not exist on this machine.
Please remember to take a backup using the vgcfgbackup command after activating the volume group.
Also, upon first activation of an imported bootable volume group, make
sure to run lvlnboot(1M) command in recovery mode (-R option) to resync
the information on the disk

# vgchange -a y /dev/vg00
Activated volume group.
Volume group "/dev/vg00" has been successfully changed.

# vgcfgbackup /dev/vg00
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf


10. Remove old device special files:

# rm /dev/*disk/disk6
# rm /dev/*disk/disk7
# rm /dev/*disk/disk8
# rm /dev/*disk/disk9
# rm /dev/*disk/disk10
# rm /dev/*disk/disk11


11. Check current ioscan output:

# ioscan -NfnkC disk
Class     I  H/W Path  Driver S/W State   H/W Type     Description
===================================================================
disk      0  64000/0xfa00/0x0  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk0   /dev/rdisk/disk0
disk      1  64000/0xfa00/0x1  esdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                      /dev/disk/disk1   /dev/rdisk/disk1
disk      2  64000/0xfa00/0x2  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk2   /dev/rdisk/disk2
disk      3  64000/0xfa00/0x3  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk3   /dev/rdisk/disk3
disk      4  64000/0xfa00/0x4  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk4   /dev/rdisk/disk4
disk      5  64000/0xfa00/0x5  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk5   /dev/rdisk/disk5

Note that now the instance numbers match the device special file names.


12. Reboot the server and ensure that everything works as desired.

# vgchange -a n /dev/vg00
Volume group "/dev/vg00" has been successfully changed.

# reboot -q
ERROR:   The kernel configuration changes being held for next boot could
         not be applied due to a file system error.

sync'ing disks (0 buffers to flush):
 0 fcache pages still dirty
 0 buffers not flushed
 0 buffers still dirty
Calling function 5c9860 for Shutdown State 5 type 0x1

Closing oen logical volumes...
Done


13. Update /stand/bootconf file to reflect that /dev/disk/disk0 has become the boot disk device.

Set custom Instance Numbers

On ServiceGuard environments, it is frequently required to change the disk Instance Number and the corresponding Device Special File to have a consistent disk configuration across multiple nodes.

To accomplish this task, usage of a infile with the ioinit command may be required.

For example, assume that in previous example, the Agile device for devices disk2, disk3 and disk4 are desired to be renumber to 100 + n above, to clearly identified SAN devices.

# ioscan -NfnkC disk 
Class     I  H/W Path  Driver S/W State   H/W Type     Description
===================================================================
disk      0  64000/0xfa00/0x0  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk0   /dev/rdisk/disk0
disk      1  64000/0xfa00/0x1  esdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                      /dev/disk/disk1   /dev/rdisk/disk1
disk      2  64000/0xfa00/0x2  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk2   /dev/rdisk/disk2
disk      3  64000/0xfa00/0x3  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk3   /dev/rdisk/disk3
disk      4  64000/0xfa00/0x4  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk4   /dev/rdisk/disk4
disk      5  64000/0xfa00/0x5  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk5   /dev/rdisk/disk5

1. Create an infile

# ioscan -fnkNC disk | grep -e ^disk -e /dev > /tmp/ioscan.out

# awk '$1 ~ /^disk/ {printf "%s\tdisk\t%d\n", $3, $2}' /tmp/ioscan.out > /tmp/infile

# cat /tmp/infile
64000/0xfa00/0x0        disk    0
64000/0xfa00/0x1        disk    1
64000/0xfa00/0x2        disk    2
64000/0xfa00/0x3        disk    3
64000/0xfa00/0x4        disk    4
64000/0xfa00/0x5        disk    5


2. Modify the infile to reflect the desire change.

# cat /tmp/infile
64000/0xfa00/0x0        disk    0
64000/0xfa00/0x1        disk    1
64000/0xfa00/0x2        disk    2
64000/0xfa00/0x3        disk    103
64000/0xfa00/0x4        disk    104
64000/0xfa00/0x5        disk    105


3. Use ionit command to load the modified infile. Use the -A flag to automatically delete the old device special files.

# ioinit -f /tmp/infile -A
ioinit: Input is identical to kernel, line ignored
Input line 1:  64000/0xfa00/0x0 disk    0

ioinit: Input is identical to kernel, line ignored
Input line 2:  64000/0xfa00/0x1 disk    1

ioinit: Input is identical to kernel, line ignored
Input line 3:  64000/0xfa00/0x2 disk    2

# ioscan -NfnkC disk
Class     I  H/W Path  Driver S/W State   H/W Type     Description
===================================================================
disk      0  64000/0xfa00/0x0  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk0   /dev/rdisk/disk0
disk      1  64000/0xfa00/0x1  esdisk   CLAIMED     DEVICE       TEAC    DV-28E-N
                      /dev/disk/disk1   /dev/rdisk/disk1
disk      2  64000/0xfa00/0x2  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk2   /dev/rdisk/disk2
disk    103  64000/0xfa00/0x3  esdisk   CLAIMED     DEVICE       HP 36.4GST336753LC
                      /dev/disk/disk103   /dev/rdisk/disk103
disk    104  64000/0xfa00/0x4  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk104   /dev/rdisk/disk104
disk    105  64000/0xfa00/0x5  esdisk   CLAIMED     DEVICE       HP 36.4GST336754LC
                      /dev/disk/disk105   /dev/rdisk/disk105
NOTE: The -A flag in the ionit command required that at least PHCO_38062 - "11.31 ioinit(1M) cumulative patch" is installed in the system to handle the device file renaming operation.


4. Reboot the system to ensure that the changes are preserve.

NOTE: From this moment, every time that a new disk or LUN is presented to the server, the lowest next available instance number will be assigned to it. Repeat this procedure, limited to the new device, to maintain the naming scheme that best suits your environment

Reference

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This page was last modified on 26 May 2011, at 20:12. This page has been accessed 7,957 times.