Unix-India: February 2011

Tuesday, 22 February 2011

Renaming Volume Group in HP Unix

Renaming VG in hpux.
Here is the procedure for renaming a VG in hpux. Renaming a VG is simple as exporting the the VG as importing with different name. (eg: vgapp to vgdb)
1. Verify the existing configuration

#vgdisplay vgapp
VG Name /dev/vgapp
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 2
Open LV 2
Max PV 16
Cur PV 4
Act PV 4
Max PE per PV 1016
VGDA 8
PE Size (Mbytes) 32
Total PE 508
Alloc PE 336
Free PE 172
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0
VG Version 1.0
VG Max Size 508g
VG Max Extents 16256

1. Umount all the logical volume from vgapp.
# bdf|grep vgapp
/dev/vgapp/test1 10485760 20062 9811599 0% /apps/test1
# umount /apps/test1

2. Deactivate Vg.

# vgchange -a n vgapp
Volume group "vgapp" has been successfully changed.

3. Create a map file which can be used whileimporting back . File name is /tmp/vgapp

# vgexport -v \ # -->
-p \ # Preview the actions to be taken without updating lvmtab
-s \ # Scan option for creating map file
-m /tmp/vgapp vgapp #description of the volume group and its associated logical volume
Beginning the export process on Volume Group "vgapp".
/dev/disk/disk38
/dev/disk/disk39
/dev/disk/disk40
/dev/disk/disk41
vgexport: Preview of vgexport on volume group "vgapp" succeeded.

4. Export VG

# vgexport vgapp
vgexport: Volume group "vgapp" has been successfully removed.

5. Create device files for vgdb

root@rx16-243 [/root]
# ls -l /dev/*/group
crw-r----- 1 root sys 64 0x000000 Feb 18 20:30 /dev/vg00/group
# mknod /dev/vgdb/group c 64 0x010000
# ls -l /dev/*/group
crw-r----- 1 root sys 64 0x000000 Feb 18 20:30 /dev/vg00/group
crw-r--r-- 1 root sys 64 0x010000 Feb 20 04:36 /dev/vgdb/group

6. Import the VG with new name using the mapfile
# vgimport -s -N -m /tmp/vgapp vgdb
vgimport: Volume group "/dev/vgdb" 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.
Note: -N is for pvlink to be in new persistant dsf naming

7. Activate the new VG.

# vgchange -a y vgdb
Activated volume group.
Volume group "vgdb" has been successfully changed.

8. Verify the VG and mount the volume

# vgdisplay -v vgdb
--- Volume groups ---
VG Name /dev/vgdb
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 2
Open LV 2
Max PV 16
Cur PV 4
Act PV 4
Max PE per PV 1016
VGDA 8
PE Size (Mbytes) 32
Total PE 508
Alloc PE 336
Free PE 172
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0
VG Version 1.0
VG Max Size 508g
VG Max Extents 16256

   --- Logical volumes ---
   LV Name /dev/vgdb/test
   LV Status available/syncd
   LV Size (Mbytes) 512
   Current LE 16
   Allocated PE 16
   Used PV 1

   LV Name /dev/vgdb/test1
   LV Status available/syncd
   LV Size (Mbytes) 10240
   Current LE 320
   Allocated PE 320
   Used PV 3

   --- Physical volumes ---
   PV Name /dev/disk/disk38
   PV Status available
   Total PE 127
   Free PE 0
   Autoswitch On
   Proactive Polling On

   PV Name /dev/disk/disk39
   PV Status available
   Total PE 127
   Free PE 0
   Autoswitch On
   Proactive Polling On

   PV Name /dev/disk/disk40
   PV Status available
   Total PE 127
   Free PE 45
   Autoswitch On
   Proactive Polling On

   PV Name /dev/disk/disk41
   PV Status available
   Total PE 127
   Free PE 127
   Autoswitch On
   Proactive Polling On
# mount /dev/vgdb/test1 /mnt
# bdf /mnt
Filesystem kbytes used avail %used Mounted on
/dev/vgdb/test1 10485760 20062 9811599 0% /mnt

Saturday, 19 February 2011

Mirroring HP-UX root disk on Itanium-based systems

1. Setup the disk partitions
Create a partition description file:
# vi /tmp/partitionfile
3
EFI 100MB
HPUX 100%
HPSP 400MB

2. Use the idisk(1M) command to partition the disk according to this file:

# idisk -wf /tmp/partitionfile /dev/rdsk/c2t0d0
idisk version: 1.44
********************** WARNING ***********************
If you continue you may destroy all data on this disk.
Do you wish to continue(yes/no)? yes

EFI Primary Header:
   Signature = EFI PART
   Revision = 0x10000
   HeaderSize = 0x5c
   HeaderCRC32 = 0x4ef8e40b
   MyLbaLo = 0x1
   MyLbaHi = 0x0
   AlternateLbaLo = 0x88bb991
   AlternateLbaHi = 0x0
   FirstUsableLbaLo = 0x40
   FirstUsableLbaHi = 0x0
   LastUsableLbaLo = 0x88bb93f
   LastUsableLbaHi = 0x0
   Disk GUID = 68847bb2-3c12-11e0-8000-d6217b60e588
   PartitionEntryLbaLo = 0x2
   PartitionEntryLbaHi = 0x0
   NumberOfPartitionEntries = 0xc
   SizeOfPartitionEntry = 0x80
   PartitionEntryArrayCRC32 = 0x60f72440

  Primary Partition Table (in 512 byte blocks):
   Partition 1 (EFI):
   Partition Type GUID = c12a7328-f81f-11d2-ba4b-00a0c93ec93b
   Unique Partition GUID = 68847e78-3c12-11e0-8000-d6217b60e588
   Starting Lba Lo = 0x40
   Starting Lba Hi = 0x0
   Ending Lba Lo = 0xf9fff
   Ending Lba Hi = 0x0
   Partition 2 (HP-UX):
   Partition Type GUID = 75894c1e-3aeb-11d3-b7c1-7b03a0000000
   Unique Partition GUID = 68847e96-3c12-11e0-8000-d6217b60e588
   Starting Lba Lo = 0xfa000
   Starting Lba Hi = 0x0
   Ending Lba Lo = 0x87f3fff
   Ending Lba Hi = 0x0
   Partition 3 (HPSP):
   Partition Type GUID = e2a1e728-32e3-11d6-a682-7b03a0000000
   Unique Partition GUID = 68847eaa-3c12-11e0-8000-d6217b60e588
   Starting Lba Lo = 0x87f4000
   Starting Lba Hi = 0x0
   Ending Lba Lo = 0x88bb93f
   Ending Lba Hi = 0x0

EFI Alternate Header:
   Signature = EFI PART
   Revision = 0x10000
   HeaderSize = 0x5c
   HeaderCRC32 = 0x1ce467d8
   MyLbaLo = 0x88bb991
   MyLbaHi = 0x0
   AlternateLbaLo = 0x1
   AlternateLbaHi = 0x0
   FirstUsableLbaLo = 0x40
   FirstUsableLbaHi = 0x0
   LastUsableLbaLo = 0x88bb93f
   LastUsableLbaHi = 0x0
   Disk GUID = 68847bb2-3c12-11e0-8000-d6217b60e588
   PartitionEntryLbaLo = 0x88bb971
   PartitionEntryLbaHi = 0x0
   NumberOfPartitionEntries = 0xc
   SizeOfPartitionEntry = 0x80
   PartitionEntryArrayCRC32 = 0x60f72440

  Alternate Partition Table (in 512 byte blocks):
   Partition 1 (EFI):
   Partition Type GUID = c12a7328-f81f-11d2-ba4b-00a0c93ec93b
   Unique Partition GUID = 68847e78-3c12-11e0-8000-d6217b60e588
   Starting Lba Lo = 0x40
   Starting Lba Hi = 0x0
   Ending Lba Lo = 0xf9fff
   Ending Lba Hi = 0x0
   Partition 2 (HP-UX):
   Partition Type GUID = 75894c1e-3aeb-11d3-b7c1-7b03a0000000
   Unique Partition GUID = 68847e96-3c12-11e0-8000-d6217b60e588
   Starting Lba Lo = 0xfa000
   Starting Lba Hi = 0x0
   Ending Lba Lo = 0x87f3fff
   Ending Lba Hi = 0x0
   Partition 3 (HPSP):
   Partition Type GUID = e2a1e728-32e3-11d6-a682-7b03a0000000
   Unique Partition GUID = 68847eaa-3c12-11e0-8000-d6217b60e588
   Starting Lba Lo = 0x87f4000
   Starting Lba Hi = 0x0
   Ending Lba Lo = 0x88bb93f
   Ending Lba Hi = 0x0

Legacy MBR (MBR Signatures in little endian):
MBR Signature = 0x4e7b8468

Protective MBR

3. Create device files needed for the new partitions.

# insf -eC disk
##Listing the new partitions
# ioscan -funNCdisk
Class I H/W Path Driver S/W State H/W Type Description
===================================================================
disk 35 64000/0xfa00/0x0 esdisk CLAIMED DEVICE HP 73.4GMAX3073NC

                      /dev/disk/disk35      /dev/disk/disk35_p2   /dev/rdisk/disk35     /dev/rdisk/disk35_p2

                      /dev/disk/disk35_p1   /dev/disk/disk35_p3   /dev/rdisk/disk35_p1  /dev/rdisk/disk35_p3

disk 36 64000/0xfa00/0x1 esdisk CLAIMED DEVICE HP 73.4GMAX3073NC

                      /dev/disk/disk36      /dev/disk/disk36_p2   /dev/rdisk/disk36     /dev/rdisk/disk36_p2

                      /dev/disk/disk36_p1   /dev/disk/disk36_p3   /dev/rdisk/disk36_p1  /dev/rdisk/disk36_p3

4. Verify the partition table.

# idisk /dev/rdsk/c2t0d0
# idisk /dev/rdsk/c2t0d0
idisk version: 1.44

Legacy MBR (MBR Signatures in little endian):
MBR Signature = 0x4e7b8468

Protective MBR

5. Verify that the device files were created properly.

# ioscan -efnC disk --> c2t0d0 is 0/1/1/0.0.0

6. Initialize the efi partition for use.

# efi_fsinit -d /dev/rdsk/c2t0d0s1

7. Populate the /efi/hpux/ directory in the new EFI system partition.

# mkboot -e -l /dev/rdsk/c2t0d0
##Here we can verify the contends.
# efi_ls -d /dev/rdsk/c2t0d0s1
FileName Last Modified Size
EFI/ 2/19/2011 0
startup.nsh 2/19/2011 296

total space 523218944 bytes, free space 520163328 bytes

8. Change the auto file for the mirror to boot without quorum.
NOTE: Using "s1"

# echo "boot vmunix -lq" > /tmp/AUTO.lq
# efi_cp -d /dev/rdsk/c2t0d0s1 /tmp/AUTO.lq /EFI/HPUX/AUTO

NOTE: We assume that if we boot from the primary, the mirror is fully
functional and therefore we don't need to override quorum. Your site
might require that both disks override quorum.

9. Verify the contents of the auto file on the primary and the mirror.
NOTE: Using "s1"

root@rx16-243 [/root]
# efi_cp -d /dev/rdsk/c2t1d0s1 -u /EFI/HPUX/AUTO /tmp/AUTO.pri

root@rx16-243 [/root]
# efi_cp -d /dev/rdsk/c2t0d0s1 -u /EFI/HPUX/AUTO /tmp/AUTO.sec

root@rx16-243 [/root]
# cat /tmp/AUTO.pri
boot vmunix

root@rx16-243 [/root]
# cat /tmp/AUTO.sec
boot vmunix -lq

10. Create PV and add the new partition to vg00.

NOTE: Using "s2"

# pvcreate -fB /dev/rdsk/c2t0d0s2
Physical volume "/dev/rdsk/c2t0d0s2" has been successfully created.

# vgextend vg00 /dev/dsk/c2t0d0s2
Volume group "vg00" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf

11. Mirror all logical volumes in vg00.

NOTE: Using "s2"

for i in `vgdisplay -v vg00 |grep lv|awk -F\/ {'print $4'}`
do
echo "Extending $i"
lvextend -m 1 /dev/vg00/$i /dev/dsk/c2t0d0s2
done

##this is the exptected output.
Extending lvol1
lvextend: "MirrorCopies" parameter "1" must be larger than existing number "1".
Extending lvol2
The newly allocated mirrors are now being synchronized. This operation will
take some time. Please wait ....
Logical volume "/dev/vg00/lvol2" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf
Extending lvol3
The newly allocated mirrors are now being synchronized. This operation will
take some time. Please wait ....
Logical volume "/dev/vg00/lvol3" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf
Extending lvol4
The newly allocated mirrors are now being synchronized. This operation will
take some time. Please wait ....
Logical volume "/dev/vg00/lvol4" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf
Extending lvol5
The newly allocated mirrors are now being synchronized. This operation will
take some time. Please wait ....
Logical volume "/dev/vg00/lvol5" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf
Extending lvol6
The newly allocated mirrors are now being synchronized. This operation will
take some time. Please wait ....
Logical volume "/dev/vg00/lvol6" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf
Extending lvol7
The newly allocated mirrors are now being synchronized. This operation will
take some time. Please wait ....
Logical volume "/dev/vg00/lvol7" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf
Extending lvol8
The newly allocated mirrors are now being synchronized. This operation will
take some time. Please wait ....
Logical volume "/dev/vg00/lvol8" has been successfully extended.
Volue Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf

For checking the status of current sysncing. (Eg. For lvol6)

# lvdisplay -v /dev/vg00/lvol6|grep stale|wc -l
26

12. Add the new disk to /stand/bootconf.
NOTE: Using "s2"

# echo "l /dev/dsk/c2t0d0s2" >> /stand/bootconf

# cat /stand/bootconf
l /dev/disk/disk36_p2
l /dev/dsk/c2t0d0s2

13. Verify that the new disk was added to vg00, and the lv's are in sync.

# vgdisplay -v vg00
--- Volume groups ---
VG Name /dev/vg00
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 8
Open LV 8
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 4329
VGDA 4
PE Size (Mbytes) 16
Total PE 8638
Alloc PE 4324
Free PE 4314
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0
VG Version 1.0
VG Max Size 1108224m
VG Max Extents 69264

   --- Logical volumes ---
   LV Name /dev/vg00/lvol1
   LV Status available/syncd
   LV Size (Mbytes) 1792
   Current LE 112
   Allocated PE 224
   Used PV 2

   LV Name /dev/vg00/lvol2
   LV Status available/syncd
   LV Size (Mbytes) 6144
   Current LE 384
   Allocated PE 768
   Used PV 2

   LV Name /dev/vg00/lvol3
   LV Status available/syncd
   LV Size (Mbytes) 1024
   Current LE 64
   Allocated PE 128
   Used PV 2

   LV Name /dev/vg00/lvol4
   LV Status available/syncd
   LV Size (Mbytes) 512
   Current LE 32
   Allocated PE 64
   Used PV 2

   LV Name /dev/vg00/lvol5
   LV Status available/syncd
   LV Size (Mbytes) 112
   Current LE 7
   Allocated PE 14
   Used PV 2

   LV Name /dev/vg00/lvol6
   LV Status available/syncd
   LV Size (Mbytes) 12096
   Current LE 756
   Allocated PE 1512
   Used PV 2

   LV Name /dev/vg00/lvol7
   LV Status available/syncd
   LV Size (Mbytes) 6256
   Current LE 391
   Allocated PE 782
   Used PV 2

   LV Name /dev/vg00/lvol8
   LV Status available/syncd
   LV Size (Mbytes) 6656
   Current LE 416
   Allocated PE 832
   Used PV 2

   --- Physical volumes ---
   PV Name /dev/disk/disk36_p2
   PV Status available
   Total PE 4319
   Free PE 2157
   Autoswitch On
   Proactive Polling On

   PV Name /dev/dsk/c2t0d0s2
   PV Status available
   Total PE 4319
   Free PE 2157
   Autoswitch On
   Proactive Polling On

14. Verify that the BDRA was updated properly. Take note of the HW paths for
step 15.

# lvlnboot -v
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
   /dev/disk/disk36_p2 -- Boot Disk
   /dev/dsk/c2t0d0s2 -- Boot Disk
Boot: lvol1 on: /dev/disk/disk36_p2
   /dev/dsk/c2t0d0s2
Root: lvol3 on: /dev/disk/disk36_p2
   /dev/dsk/c2t0d0s2
Swap: lvol2 on: /dev/disk/disk36_p2
   /dev/dsk/c2t0d0s2
Dump: lvol2 on: /dev/disk/disk36_p2, 0

15. Add EFI primary and high availability boot path menu entries.

# ioscan -funCdisk|more
Class I H/W Path Driver S/W State H/W Type Description
=======================================================================
disk 2 0/0/2/0.0.0.0 sdisk CLAIMED DEVICE _NEC DVD+-RW ND-6650A
/dev/dsk/c0t0d0 /dev/rdsk/c0t0d0
disk 0 0/1/1/0.0.0 sdisk CLAIMED DEVICE HP 73.4GMAX3073NC

                           /dev/dsk/c2t0d0     /dev/dsk/c2t0d0s2   /dev/rdsk/c2t0d0    /dev/rdsk/c2t0d0s2

                           /dev/dsk/c2t0d0s1   /dev/dsk/c2t0d0s3   /dev/rdsk/c2t0d0s1  /dev/rdsk/c2t0d0s3

disk 1 0/1/1/0.1.0 sdisk CLAIMED DEVICE HP 73.4GMAX3073NC

                           /dev/dsk/c2t1d0     /dev/dsk/c2t1d0s2   /dev/rdsk/c2t1d0    /dev/rdsk/c2t1d0s2

                           /dev/dsk/c2t1d0s1   /dev/dsk/c2t1d0s3   /dev/rdsk/c2t1d0s1  /dev/rdsk/c2t1d0s3

# setboot -p 0/1/1/0.1.0 <-- Set primary disk
# setboot -h 0/1/1/0.0.0 <-- Set mirror disk
# setboot -b on <-- Set autoboot on

16. Verify that the primary and mirror boot paths are configured properly.

# setboot
Primary bootpath : 0/1/1/0.0x1.0x0 (/dev/rdisk/disk36)
HA Alternate bootpath : 0/1/1/0.0x0.0x0 (/dev/rdisk/disk35)
Alternate bootpath : 0/1/1/0.0x0.0x0 (/dev/rdisk/disk35)

Autoboot is ON (enabled)

17. Test the new mirror by booting off of it.

# shutdown -r -y 0
18. Select "HP-UX HA Alternate Boot" to test the mirror while EFI Display below messages.

Please select a boot option

   HP-UX Primary Boot: 0/1/1/0.0x1.0x0
   HP-UX HA Alternate Boot: 0/1/1/0.0x0.0x0
   HP-UX Alternate Boot: 0/1/1/0.0x0.0x0
   EFI Shell [Built-in]
   Boot Option Maintenance Menu
   System Configuration

Use ^ and v to change option(s). Use Enter to select an option
Scsi(Pun0,Lun0) HP 73.4GMAX3073NC HPC1 (320 MBytes/sec)
Loading.: HP-UX HA Alternate Boot: 0/1/1/0.0x0.0x0
Starting: HP-UX HA Alternate Boot: 0/1/1/0.0x0.0x0

HP-UX Boot Loader for IPF -- Revision 2.039

Press Any Key to interrupt Autoboot
\EFI\HPUX\AUTO ==> boot vmunix -lq
Seconds left till autoboot - 8

20. Verify which disk/kernel you booted from.

# grep "Boot device" /var/adm/syslog/syslog.log
Feb 19 06:18:41 rx16-243 vmunix: Boot device's HP-UX HW path is: 0.1.1.0.0.0

21. Remove temporary files.

# rm /tmp/partitionfile /tmp/AUTO*

Monday, 14 February 2011

Extending HP-UX LVM

1. Make sure we have enough space in VG before extend.

#vgdisplay dbmdws|egrep 'Free PE|PE Size'
Multiplying this Free PE and PE size will provide the free size in MB in this VG.

2. Here we extend the LV to 100G (the rusulting FS will be in 100G size (-L in MB 100Gx100)

#/usr/sbin/lvextend -L 102400 /dev/oracle-vg/lvoracle
Logical volume "/dev/oracle-vg/lvoracle" has been successfully extended.

3. Online extending Filesystem to the new size (-b KB (100Gx1024x1024)

#/usr/sbin/fsadm -F vxfs -b 104857600 /oracle
#bdf /dev/oracle-vg/lvoracle
104857600 10252151 88692620 10% /oracle

Wednesday, 9 February 2011

Perl script for getting Public IP from Linux

I used this script from LAN for getting my public IP which is obtained from ISP's DHCP server to my Modem

# cat getwanip.pl
#!/usr/bin/perl -w
#Owner :latheefp@gmail.com
#Purpose :Getting Public IP from Linux/Unix"
#Packages Required: Perl and wget
my $external_ip;
$external_ip = `wget -q -O - "http://checkip.dyndns.org"`;
if($external_ip =~ m/(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})/) {
print "My Wan IP is $1\n";
}

The output will be similar to this.

[root@RH31 scripts]# ./getwanip.pl

My Wan IP is 178.74.XXX.221

Saturday, 5 February 2011

Changing kernel parameters in HP-UX

Changing kernel parameters in HP-UX.

While Installing DB it failed due to below kernel parameters

Checking for maxssiz=134217728; maxssiz=8388608. Failed <<<<
Checking for maxssiz_64bit=1073741824; maxssiz_64bit=268435456. Failed <<<<
Checking for maxuprc=3687; maxuprc=3686. Failed <<<<
Checking for semmns=8192; semmns=4096. Failed <<<<

I resolved this issue by setting this parameters using kctune command as below.

For verifying the current Value

# kctune -v for maxssiz maxssiz_64bit maxuprc semmns
Tunable maxssiz
Description Maximum size of the stack segment of a 32-bit process (bytes)
Module vm
Current Value 8388608 [Default]
Value at Next Boot 8388608 [Default]
Value at Last Boot 8388608
Default Value 8388608
Constraints maxssiz >= 262144
maxssiz <= 401604608
Can Change Immediately or at Next Boot

Tunable maxssiz_64bit
Description Maximum size of the stack segment of a 64-bit process (bytes)
Module vm
Current Value 268435456 [Default]
Value at Next Boot 268435456 [Default]
Value at Last Boot 268435456
Default Value 268435456
Constraints maxssiz_64bit >= 262144
maxssiz_64bit <= 2147483648
Can Change Immediately or at Next Boot

Tunable maxuprc
Description Maximum number of processes for each non-root user
Module pm_proc
Current Value 3686 [((nproc*9)/10)]
Value at Next Boot 3687
Value at Last Boot 3686
Default Value 256
Constraints maxuprc >= 3
maxuprc <= nproc - 5
Can Change Immediately or at Next Boot

Tunable semmns
Description Maximum number of semaphores
Module pm_usync
Current Value 4096 [Default]
Value at Next Boot 4096
Value at Last Boot 4096
Default Value 4096
Constraints semmns >= 2
   semmns <= 335534080
   semmns >= semmni
   semmns >= semume
Can Change At Next Boot Only

For changing the Value:

# kctune maxssiz=134217728
   ==> Update the automatic 'backup' configuration first? yes
   yes - Update backup before every change
   once - Update backup now; ask for each future change
   no - Don't update backup now; ask for each future change
   disable - Don't update backup before any change
   ==> Update the automatic 'backup' configuration first? yes
   * The automatic 'backup' configuration has been updated.
   * Future operations will update the backup without prompting.
   * The requested changes have been applied to the currently
   running configuration.
Tunable Value Expression Changes
maxssiz (before) 8388608 Default Immed
   (now) 134217728 134217728

# kctune maxssiz_64bit=1073741824
   * The automatic 'backup' configuration has been updated.
   * The requested changes have been applied to the currently
   running configuration.
Tunable Value Expression Changes
maxssiz_64bit (before) 268435456 Default Immed
   (now) 1073741824 1073741824

# kctune maxuprc=3687
   * The automatic 'backup' configuration has been updated.
   * The requested changes have been applied to the currently
   running configuration.
Tunable Value Expression Changes
maxuprc (before) 3686 ((nproc*9)/10) Immed
   (now) 3687 3687

# kctune semmns=8192
NOTE: The requested changes could not be applied to the currently
   running system, for the following reasons:
   - The tunable 'semmns' cannot be changed without a reboot.
   * The requested changes have been saved, and will take effect at
   next boot.
NOTE: No change to the tunable 'semmns' was needed.
Tunable Value Expression
semmns (now) 4096 Default
   (next boot) 8192 8192

After Changing the value using kctune command, it require a reboot of the system for some of the value to get effected. As show below output.

# kctune -v for maxssiz maxssiz_64bit maxuprc semmns
Tunable maxssiz
Description Maximum size of the stack segment of a 32-bit process (bytes)
Module vm
Current Value 134217728
Value at Next Boot 134217728
Value at Last Boot 134217728
Default Value 8388608
Constraints maxssiz >= 262144
   maxssiz <= 401604608
Can Change Immediately or at Next Boot

Tunable maxssiz_64bit
Description Maximum size of the stack segment of a 64-bit process (bytes)
Module vm
Current Value 1073741824
Value at Next Boot 1073741824
Value at Last Boot 1073741824
Default Value 268435456
Constraints maxssiz_64bit >= 262144
maxssiz_64bit <= 2147483648
Can Change Immediately or at Next Boot

Tunable maxuprc
Description Maximum number of processes for each non-root user
Module pm_proc
Current Value 3687
Value at Next Boot 3687
Value at Last Boot 3687
Default Value 256
Constraints maxuprc >= 3
maxuprc <= nproc - 5
Can Change Immediately or at Next Boot

Tunable semmns
Description Maximum number of semaphores
Module pm_usync
Current Value 8192
Value at Next Boot 8192
Value at Last Boot 8192
Default Value 4096
Constraints semmns >= 2
   semmns <= 335534080
   semmns >= semmni
   semmns >= semume
Can Change At Next Boot Only

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