Replicating a desired AIX configuration in IBM® Power® Virtual Server using an AIX mksysb image
Learn how to create and restore an AIX mksysb
image onto an IBM® Power® Virtual Server instance.
A simple way to migrate a local AIX environment (or workload) into Power Virtual Server is to restore an operating system rootvg
backup over an existing image and then migrate the data. The rootvg
backup is created with
the AIX mksysb
command. The restored mksysb image applies the AIX configuration details while preserving the Power Virtual Server deployed storage and networking resources.
when the restored AIX configuration is active, various methods can be used to migrate applications and related data. Those methods are outside the scope of this page.
It is assumed the reader has AIX administration experience and is familiar with deploying a Power Virtual Server AIX instance by using the Power Virtual Server user interface or the IBM Cloud CLI.
Considerations before creating the mksysb image on the source AIX instance
-
Ensure that the installed RSCT package is at version 3.2.6.2 or later. The
/opt/rsct/install/bin/ctversion
command can be used to display the installed version. For more information see, Recommended Reliable Scalable Cluster Technology (RSCT) package levels for imported AIX images. -
The AIX environment should be running an AIX version and technology level that is in standard support. For AIX levels that are under an extended support model, arrangements should be made to obtain an extended support agreement to cover the use of the AIX level in Power Virtual Server.
Consult the General AIX support lifecycle information and FAQ on OS versions that are supported for more details.
The AIX instance that is deployed in the Power Virtual Server should be at the same AIX version as the source AIX instance. For example, if the source instance is at AIX 7.2, then the deployed Power Virtual Server instance should also be a 7.2 based image.
The AIX technology levels (TL) do not need to match, but you might consider by using the latest TL that is available from the Power Virtual Server stock images.
- Ensure that that NPIV file sets are installed in the AIX environment as Power Virtual Server VMs use the NPIV storage virtualization model. This can be checked by using the lslpp command as follows.
#
# lslpp -l devices.vdevice.IBM.vfc-client.rte
Fileset Level State Description
-------------------------------------------------------------
Path: /usr/lib/obj repos
devices.vdevice.IBM.vfc-client.rte
7.1.5.38 COMMITTED Virtual Fibre Channel Client Support
Path: /etc/obj repos
devices.vdevice.IBM.vfc-client.rte
7.1.5.38 COMMITTED Virtual Fibre Channel Client Support
#
-
Verify that the AIX initab file does not contain entries with dependencies on unique aspects of the source environment that would not be present in Power Virtual Server. Otherwise, the converted Power Virtual Server AIX instance might not boot. Similarly, if other boot time actions exist such as NFS file system mounts, those might need to be disabled.
-
Power Virtual Server uses IBM Storage with the built-in AIX MPIO driver. Enure that the I/O configuration of the source LPAR does not conflict with the use of AIX MPIO.
-
Delete any temporary files or files, especially large files that are not necessary on the target Power Virtual Server AIX instance. The
-e
and-x
mksysb options can also be used to exclude unneeded directories and file systems in rootvg. This reduces the size of the mksysb image for transfer to Power Virtual Server.
Creating the mksysb image on the source AIX instance
Refer to the mksysb documentation for full details on the command usage. Ensure that there is sufficient file system space to hold the produced mksysb image. Generally, 10 to 15 GB is sufficient depending on additional non-AIX data added to the rootvg.
In the following example, mksysb creates the image in /tmp. The -i
builds the image from the latest rootvg details and the -b
option can potentially improve the performance when creating the mksysb image. The -X
mksysb option expands /tmp
if necessary for the boot image. This can be omitted if the available space is known to be sufficient.
# create the mksysb image
mksysb -i -X -C -b 512 /tmp/my-mksysb
Once the mksysb image is created, the storage volume size that is necessary to restore of the image can be extracted as follows. In this example, a 25 GB volume would be necessary.
#
# restore -qf ./my-mksysb ./bosinst.data
x ./bosinst.data
# fgrep -p target_disk_data bosinst.data|fgrep SIZE_MB
SIZE MB = 25600
# rm bosinst.data
#
Also, capture the image checksum for verification once the image is transferred to a Power Virtual Server AIX instance for restoration.
#
# cksum ./my-mksysb
1999777825 1861746688 ./my-mksysb
#
Creating a Power Virtual Server AIX instance for conversion with an mksysb image
An AIX instance is required in Power Virtual Server that can be converted with the mksysb image.
The instance must be at the same AIX version as the AIX instance where the mksyb image was created. Power Virtual Server provides a set of stock images that can be used to facilitate the conversion. When deployed, the AIX instance needs some updates to host the mksysb image. Choose the stock image and deploy a new Power Virtual Server AIX instance via the user interface or CLI with the cpu, memory, and network details that are required for the final converted instance.
For example, if an AIX 7.2 based mksysb image is being used, choose the 7200-05-05
stock image. When deploying the instance, attach an additional storage volume with sufficient capacity for the mksysb image restore. Use the information
from the bosinst.data file to get the minimum required size in Megabytes. Below is an example AIX 7.2 deployed instance with an additional 30 GB volume (hdisk1).
The following details should be observed with the deployed AIX instance.
#
# oslevel -s
7200-05-05-2246
# lspv
hdiskO 00fa00d66c59c9d7 rootvg active
hdiskl none None
# bootinfo -s hdiskl
30720
#
To make room for the mksysb image, disk space must be freed in the instance to hold it. This can be done by removing the /usr/sys/inst.images
file system and creating a new one called /mksysb-staging
.
This should result in sufficient space for most mksysb image use cases. If more space is required, then a new larger storage volume needs to be attached to the instance with the Power Virtual Server user interface and a JFS2 file system will
need to be created on it. The following example removes /usr/sys/inst.images
and creates a new 12 GB mksysb-staging
file system.
#
# umount /usr/sys/inst.images
# rmfs -r /usr/sys/inst.images
rmlv: Logical volume repo00 is removed.
#
#
# crfs -v jfs2 -g rootvg -m /mksysb-staging -a size=12G
File system created successfully.
12582324 kilobytes total disk space.
New File System size is 25165824
# mount /mksysb-staging
# mount
node mounted mounted over vfs date options
-------- --------------- --------------- ------ ------------ ---------------
/dev/hd4 / jfs2 Oct 11 17:47 rw,log=/dev/hd8
/dev/hd2 /usr jfs2 Oct 11 17:47 rw,log=/dev/hd8
/dev/hd9var /var jfs2 Oct 11 17:47 rw,log=/dev/hd8
/dev/hd3 /tmp jfs2 Oct 11 17:48 rw,log=/dev/hd8
/dev/hd1 /home jfs2 Oct 11 17:48 rw,log=/dev/hd8
/dev/hdlladmin /admin jfs2 Oct 11 17:48 rw,log=/dev/hd8
/proc /proc procfs Oct 11 17:48 rw
/dev/hd10opt /opt jfs2 Oct 11 17:48 rw,log=/dev/hd8
/dev/lLivedump /var/adm/ras/livedump jfs2 Oct 11 17:48 rw,log=/dev/hd8
/ahafs /aha ahafs Oct 11 17:49 rw
/dev/fslv00 /mksysb-staging jfs2 Oct 11 18:35 rw,log=/dev/hd8
#
In the preceding example, hdisk1 is the free storage volume where the mksysb image is restored.
Once the Power Virtual Server instance is created, the mksysb image is placed in the /mksysb-staging directory. Transferring the mksysb image to the /mksysb-staging
directory depends on your connectivity options to the IBM Cloud
and Power Virtual Server workspace.
For example, if you are able to access your Power Virtual Server instance over a network connection from your local system where the mksyb image resides, you might use scp.
For example,
# scp ./my-mksysb root@xxx.xxx.xxx.xxx:/mksysb-staging
Use the cksum
command to confirm the my-mksysb
image file was successfully transferred.
Now the mksysb image can be restored onto the attached free storage volume that will become the new rootvg boot disk with the configuration from the source AIX instance. This is done by using the alt_disk_mksysb command. In the following mksysb restore example, alt_disk_mksysb
sets hdisk1 as the boot disk for subsequent boots.
alt_disk_mksysb -c /dev/vty0 -d hdisk1 -m /mksysb-staging/my-mksysb
Once this completes successfully, an lspv
indicates that hdisk1 is now the altinst_rootvg.
#
# lspv
hdisk0 00fa00d66c59c9d7 rootvg active
hdisk1 00c939202144313b altinst_rootvg
The AIX bootlist
command can be used to confirm that hdisk1 is now the active AIX boot disk.
#
# bootlist -m normal -o
hdiskl blv=hd5 pathid=0
hdiskl blv=hd5 pathid=1
hdiskl blv=hd5 pathid=2
hdiskl blv=hd5 pathid=3
hdiskl blv=hd5 pathid=4
#
The AIX instance can be rebooted to the new hdisk1 rootvg.
sync;sync;shutdown -Fr
Once the AIX instance restarts, it has been converted with the mksysb image. An lspv
shows hdisk1 as the new rootvg.
#
# lspv
hdisk0 00fa00d66c59c9d7 old_rootvg
hdisk1 00c939202144313b rootvg active
#
Before proceeding, consider running some basic tests on your new converted Power Virtual Server AIX instance.
-
Run
oslevel -s
to confirm that the converted lpar matches the AIX level from the source system where the mksysb backup was created. More detailed verification can optionally be done by using thelslpp -h
command. -
In the user interface, you can test by changing the CPU and RAM with your instance. You might also try adding and removing a small storage volume. These tests confirm that the instance is properly interacting with PowerVM dynamic LPAR operations for live resource updates to the instance.
Now the old_rootvg
storage volume (hdisk0) can be detached from the instance and deleted by using the user interface. First, remove the volume from the AIX configuration with the rmdev
command.
# rmdev -dl hdisk0
Before detaching the old_rootvg
volume (hdisk0), you need to set the new rootvg volume (hdisk1) to bootable and the old_rootvg
volume to not bootable in Power Virtual Server.
Complete the following steps in Power Virtual Server user interface under the details of the AIX instance in the Attached volumes
section:
- Change the bootable indicator of the new rootvg volume from off to on.
- Set the bootable indicator of the old boot volume from on to off.
This allows the old boot volume to be detached and deleted in the Power Virtual Server user interface. This can also be done by using the IBM Cloud CLI.
When the old boot volume is detached and deleted by using the user interface, the conversion of the AIX instance by using the mksysb is complete with a single rootvg volume. Now the instance is ready for installation of applications and related data.