alt_disk_install Command

Purpose

Installs an alternate disk with a mksysb install image or clones the currently running system to an alternate disk. This command is obsolete in AIX 5.3.

Note: In AIX 5.3, the alt_disk_install command is replaced by the alt_disk_copy, alt_disk_mksysb, and alt_rootvg_op commands. The alt_disk_install module continues to be shipped as a wrapper to the new commands, but the alt_disk_install command does not support any new functions, flags, or features.

Syntax

Create Alternate Disk

 alt_disk_install { -d device | -C} [ -i image.data] [ -s script ] [ -R resolv_conf] [ -D] [ -B] [ -V] [ -r] [ -O ]
[ -p platform ] [ -L mksysb_level ] 
[ -b bundle_name ] [ -I installp_flags ]
[ -l images_location ] [ -f fix_bundle ] 
[ -F fixes ] [ -e exclude_list ] [ -w filesets ]
[ -n] [ -P phase_option ] target_disks...

Clean Up Alternate Disk Volume Group

alt_disk_install -X

For alt_disk_install or later

Determine Volume Group Boot Disk

alt_disk_install -q disk

Put-to-sleep Volume Group

alt_disk_install -S

Rename Alternate Disk Volume Group

alt_disk_install -v new_volume_group_name disk

Wake-up Volume Group

alt_disk_install  -W disk

Clean Up Alternate Disk Volume Group

alt_disk_install -X [ volume_group]

Description

Note: In AIX 5.3 the alt_disk_install command has been broken up into three commands: alt_disk_copy, alt_disk_mksysb, and alt_rootvg_op. No new functions is added to this command.

The alt_disk_install command allows users a way to update the operating system to the next release, maintenance level, or technology level, without taking the machine down for an extended period of time. This can be done in two ways, by installing a mksysb image on a separate disk, or by cloning the current system and then applying updates to get to the next maintenance or technology level.

Attention: alt_disk_install creates volume groups, logical volumes, special device files, and file systems by using the alt prefix. If alt_disk_install is used on a system, the administrator should avoid having or creating volume groups, logical volumes, special device files, or file systems with the alt prefix - alt_disk_install operations may inadvertently remove, alter, or damage these items.

The first function, installing a mksysb, requires an AIX 4.3 or later mksysb image, an AIX 4.3 or later mksysb tape, or an AIX 4.3.3 or later mksysb CD. The alt_disk_install command is called with a disk or disks that are not currently in use, and the mksysb is restored to those disks such that, if the user chooses, the next reboot boots the system on an AIX 4.3 or later system.

Note:

You cannot use alt_disk_install to install an earlier version of AIX than the one currently installed on the system. For example, you cannot install an AIX 4.3 mksysb on an AIX 5.1 system.
If needed, the bootlist command can be run after the new disk has been booted, and the bootlist can be changed to boot back to the older version of the operating system.

The second function, cloning the running rootvg, allows the user to create a backup copy of the root volume group. This copy might be used as a back up in case the rootvg failed, or it might be modified by installing additional updates. One scenario might be to clone a 4.2.0 system, then install updates to bring the cloned rootvg to 4.2.1.0. This would update the system while it was still running, then rebooting from the new rootvg would bring the level of the running system to 4.2.1. If there was a problem with this level, changing the bootlist back to the 4.2.0 disk and rebooting would bring the system back to 4.2.0. Other scenarios would include cloning the rootvg and applying individual fixes, rebooting the system and testing those fixes, and rebooting back to the original rootvg if there was a problem.

Note: NIM alternate disk migration (upgrading version or release levels) is supported by the nimadm command in AIX 5.1 and later. See the nimadm documentation for more details.

Currently, you can run the alt_disk_install command on 4.1.4.0 and higher systems for both of these functions. The bos.alt_disk_install.rte file set must be installed on the system to execute the alt_disk_install command, and the bos.alt_disk_install.boot_images file set must also be installed to perform a mksysb installation to an alternate disk.

The mksysb image that is used must be created ahead of time and have all the necessary device and kernel support that is required for the system that it's going to be installed on. No new device or kernel support can be installed before the system is rebooted from the newly installed disk.

Note: The version release maintenance or technology level of mksysb that you are installing must match the level of the bos.alt_disk_install.boot_images file set.

When cloning the rootvg volume group, a new boot image is created with the bosboot command. When installing a mksysb image, a boot image for the level of mksysb and platform type is copied to the boot logical volume for the new alternate rootvg. When the system is rebooted, the bosboot command is run in the early stage of boot, and the system is rebooted once again. This is to synchronize the boot image with the mksysb that was restored. The system then boots in normal mode.

At the end of the installation, a volume group, altinst_rootvg, is left on the target disks in the varying off state as a place holder. If varied on, it shows as owning no logical volumes, but it does indeed contain logical volumes, but they have been removed from the ODM because their names now conflict with the names of the logical volumes on the running system. It is recommended that you not vary on the altinst_rootvg volume group, but leave the definition there as a place holder.

After the system reboots from the new alternate disk, the former rootvg volume group does not show up in a lspv listing, unless the alt_disk_install version is 4.3.2 or higher.

For alt_disk_install 4.3.2 or greater

After rebooting from the new alternate disk, the former rootvg volume group shows up in a lspv listing as old_rootvg, and includes all disk(s) in the original rootvg. This former rootvg volume group is set to NOT varyon at reboot, and should ONLY be removed with the -X flag (that is, alt_disk_install -X old_rootvg).

If a return to the original rootvg is necessary, the bootlist command is used to change the bootlist to reboot from the original rootvg.

If it is unclear which disk is the boot disk for a specific volume group, the -q flag can be used to determine the boot disk. This can be useful when a volume group is consisted of multiple disks and a change in the bootlist is necessary.

The alternate root file system is mounted as /alt_inst, so other file systems would have that prefix (/alt_inst/usr, /alt_inst/var). This is how they should be accessed if using a customization script.

Attention: If you have created an alternate rootvg with alt_disk_install, but no longer want to use it, or want to run alt_disk_install commands, do not run exportvg on altinst_rootvg.

Simply run the alt_disk_install -X command to remove the altinst_rootvg definition from the ODM database. The reason that you cannot run the exportvg command (or the reducevg command) is that the logical volume names and file systems now have the real names, and exportvg removes the stanzas for the real file system from /etc/filesystems for the real rootvg.

If exportvg is run by accident, be sure to re-create the /etc/filesystems file before rebooting the system. The system will not reboot without a correct /etc/filesystems file.

This function is also available with the Network Installation Management (NIM). See the NIM Guide for more information.

The AIX 4.3.1 and greater version of alt_disk_install can be executed in phases. The installation is divided into three phases, and the default is to perform all three phases.

Table 1. Phases
Item	Description
Phase 1	Creates the altinst_rootvg volume group, the `alt_` logical volumes, the /alt_inst file systems, and restores the mksysb or rootvg data.
Phase 2	Runs any specified customization script, installs updates, new file sets, fixes, or bundles (cloning only), copies a resolv.conf file if specified, and copies files over to remain a NIM client if specified.
Phase 3	Unmounts the /alt_inst file systems, renames the file systems and logical volumes, removes the alt_ logical volumes, names ODM and varies off the `altinst_rootvg`. It sets the `bootlist` and reboots if specified.

You can run each phase separately, run Phases 1 and 2 together or run Phases 2 and 3 together. Phase 2 can be run multiple times before Phase 3 is run.

Run Phase 3 to get a volume group that is a usable rootvg. Running Phase 1 and 2 leave the /alt_inst file systems mounted.

If you have run Phase 1 and or Phase 2, and want to start over (remove the altinst_rootvg), run the alt_disk_install -X command to clean up.

If data access is necessary between the original rootvg and the new alternate disk, a volume group wake-up can be accomplished, by using the -W flag, on the non-booted volume group. The wake-up puts the volume group in a post alt_disk_install phase 1 state (i.e. the /alt_inst file systems are mounted).

Note: The volume group that experiences the wake-up is renamed altinst_rootvg.

Limitation

The running system's version of the operating system must be greater than or equal to the operating system version of the volume group that undergoes the wake-up. This may mean that it's necessary to boot from the altinst_rootvg and wake-up the old_rootvg.

For example: An alternate disk is created from an alt_disk_install 4.3.3 mksysb, on a 4.1.5 running system. To access data between the two volume groups, it is necessary to boot from the 4.3.3 alternate disk and wake-up the 4.1.5 old_rootvg volume group.

This limitation is caused by a jfs log entry incompatibility. It is possible to wake-up a volume group that contains a greater operating system version, but the volume group might not have ever been the system rootvg. If so, the volume group would have made jfs log entries that might not be interpreted by an older operating system version rootvg, when the volume group was experiencing a wake-up. JFS log entries are present for file systems that were not unmounted before a reboot, for example, /,/usr.

The alt_disk_install command will not allow a wake-up to occur on a volume group with a greater operating system version, unless the FORCE environment variable is set to yes.

Attention: If a FORCE wake-up is attempted on a volume group that contains a greater operating system version than the running operating system, AND the waking volume group has been a system rootvg, errors occur.

Note: When data access is no longer needed, the volume group can be put to sleep, by using the -S flag.

Note: The volume group that has experienced a wake-up must be put-to-sleep before it can be booted and used as the rootvg.

Flags

Table 2. Flags
Item	Description
-B	Would specify not running `bootlist` after the `mksysb` or clone. If set, the -r flag cannot be used. Note: The -B and -X flags are mutually exclusive.
-C	Clone rootvg. Note: -d and -C are mutually exclusive.
-d `device`	The value for `device` can be as `tape device - for example, /dev/rmt0` OR `path name of mksysb image in a file system.` Note: -d and -C are mutually exclusive.
-D	Turns on debug (set -x output).
-i `image.data`	Optional image.data file to use instead of default image.data from `mksysb` image or image.data created from rootvg. The image.data file name must be a full path name, for example /tmp/my_image.data. For alt_disk_install 4.3.2 or greater. If certain logical volumes need to be placed on a specific target disk, this should be annotated in the logical volume LV_SOURCE_DISK_LIST field of the user specified image.data file.
-p `platform`	This is a platform to use to create the name of the disk boot image, which may be supplied by a vendor that wanted to support this function. This flag is only valid for `mksysb` installs (-d flag).
-P`phase`	The `phase` to execute during this invocation of alt_disk_install. Valid values are: 1, 2, 3, 12, 23, or all. 12 - performs phases 1 and 2. 23 - performs phases 2 and 3. all - performs all three phases
-r	Would specify to reboot from the new disk when the alt_disk_install command is complete.
-R `resolv_conf`	The resolv.conf file to replace the existing one after the mksysb has been restored or the rootvg has been cloned. Use a full path name for `resolv_conf`.
-s `script`	Optional customization script to run at the end of the `mksysb` installation or the rootvg clone. This file must be executable. This script is called on the running system before the /alt_inst file systems are unmounted, so files can be copied from the running system to the /alt_inst file systems before the reboot. This is the only opportunity to copy or modify files in the alternate file system because the logical volume names will be changed to match rootvg, and they will not be accessible until the system is rebooted with the new alternate rootvg, or a `wake-up` is performed on the `altinst_rootvg`. Use a full path name for `script`.
-V	Turn on verbose output. This shows the files that are being backed up for rootvg clones. This flag shows files that are restored for `mksysb` alt_disk_installs.
-L `mksysb_level`	This level is combined with the platform type to create the boot image name to use (for example, rspc_4.3.0_boot in AIX 5.1 and earlier). This must be in the form V.R.M. The `mksysb` image is checked against this level to verify that they are the same.
-n	Remain a NIM client. The /.rhosts and /etc/niminfo files are copied to the alternate rootvg file system.
-X	Removes the `altinst_rootvg` volume group definition from the ODM database. This returns the lspv listing for the volume group to `None`. This will not remove actual data from the volume group. Therefore, you can still reboot from that volume group, if you reset your `bootlist`. For alt_disk_install 4.3.2 or greater, the flag allows for specified volume group name ODM database definition removal, for example, `-X old_rootvg`. Note: The -B and -X flags are mutually exclusive. If you specify the -X flag, all other flags are ignored.
-O	Performs a device reset on the target `altinst_rootvg`. This causes alt_disk_install to NOT retain any user-defined device configurations. This flag is useful if the target disk or disks become the rootvg of a different system (such as in the case of logical partitioning or system disk swap).

The following flags are only valid for use when cloning the rootvg (-C).

Table 3. Flags
Item	Description
-b `bundle_name`	Path name of optional file with a list of packages or file sets that will be installed after a rootvg clone. The -l flag must be used with this option.
-e `exclude_list`	Optional exclude.list to use when cloning rootvg. The rules for exclusion follow the pattern matching rules of the grep command. The `exclude_list` must be a full path name. Note: If you want to exclude certain files from the backup, create the /etc/exclude.rootvg file, with an ASCII editor, and enter the patterns of file names that you do not want included in your system backup image. The patterns in this file are input to the pattern matching conventions of the grep command to determine which files will be excluded from the backup. If you want to exclude files listed in the /etc/exclude.rootvg file, select the Excluded Files field and press the Tab key once to change the default value to yes. For example, to exclude all the contents of the directory called scratch, edit the exclude file to read as follows: `/scratch/` For example, to exclude the contents of the directory called /tmp, and avoid excluding any other directories that have /tmp in the path name, edit the exclude file to read as follows: `^./tmp/` All files are backed up relative to. (Current working directory). To exclude any file ordirectory for which, it is important to have the search match the string at the beginning of the line, use `^` (caret character) as the first character in the search string, followed by `.` (dot character), followed by the file name or directory to be excluded. If the file name or directory being excluded is a substring of another file name or directory, use `^.` (caret character followed by dot character) to indicate that the search should begin at the beginning of the line and/or use `$` (dollar sign character) to indicate that the search should end at the end of the line.
-f `fix_bundle`	Optional file with a list of APARs to install after a clone of rootvg. The -l flag must be used with this option.
-F `fixes`	Optional list of APARs (for example, `IX123456`) to install after a clone of rootvg. The -l flag must be used with this option.
-I `installp_flags`	The flags to use when updating or installing new file sets into the cloned alt_inst_rootvg. Default flags are `-acgX` The -l flag must be used with this option.
-l `images_location`	Location of `installp` images or updates to apply after a clone of rootvg. This can be a directory full path name or device name (like /dev/rmt0).
-w `filesets`	List of file sets to install after cloning a rootvg. The -l flag must be used with this option.

The following flags are available for alt_disk_install version 4.3.2 or greater:

Table 4. Flags
Item	Description
-q `disk`	Used to return the volume group boot disk name. This is especially useful when trying to determine the boot disk from several disks in the `old_rootvg` volume group after rebooting from the alternate disk.
-S	Will `put-to-sleep` the volume group. This is used after a volume group `wake-up`. (-W).
-v `new_volume_group_name` `disk`	Used to rename the alternate disk volume group. This is especially useful when creating multiple alternate disks, on multiple volume groups, and name identification is necessary.
-W `disk`	Used to `wake-up` a volume group for data access between the rootvg and the alternate disk rootvg. Note: The volume group that experiences the `wake-up` is renamed `altinst_rootvg`.

Limitation: The running system's version of the operating system must be greater than or equal to the operating system version of the volume group that undergoes the wake-up. This means that it's necessary to boot from the altinst_rootvg and wake-up the old_rootvg.

Parameters

Table 5. Parameters
Item	Description
`target_disks`	Specifies the name or names of the target disks where the alternate rootvg will be created. This disk or these disks must not currently contain any volume group definition. The lspv command should show these disks as belonging to volume group None.

Examples

To clone the running 4.2.0 rootvg to hdisk3, then apply updates from /updates to bring the cloned rootvg to a 4.2.1 level:
```
alt_disk_install -C -F 4.2.1.0_AIX_ML -l /updates hdisk3
```
The bootlist would then be set to boot from hdisk3 at the next reboot.
To install a 4.3 mksysb image on hdisk3, then run a customized script (/home/myscript) to copy some user files over to the alternate rootvg file systems before reboot:
```
alt_disk_install -d /mksysb_images/4.3_mksysb -s /home/myscript hdisk3
```
To remove the original rootvg ODM database entry after booting from the new alternate disk:
```
alt_disk_install -X old_rootvg
```
The lspv listing for the original rootvg will be changed to None. Therefore, a new volume group might be created on those disks.
To determine the boot disk for a volume group with multiple physical volumes:
```
alt_disk_install -q hdisk0
```
The following is an example of the output:
```
# lspv
hdisk0          00006091aef8b687     old_rootvg
hdisk1          00076443210a72ea     rootvg
hdisk2          0000875f48998649     old_rootvg
# alt_disk_install -q hdisk0
hdisk2
```
In this case, the boot disk for old_rootvg is hdisk2. Therefore, you might reset your bootlist to hdisk2 and reboot to the original rootvg volume group.

To modify an alt_disk_install volume group name:

alt_disk_install -v alt_disk_432 hdisk2

The following is an example of the output:

# lspv
hdisk0          00006091aef8b687     rootvg
hdisk1          00000103000d1a78     rootvg
hdisk2          000040445043d9f3     altinst_rootvg
hdisk3          00076443210a72ea     altinst_rootvg
hdisk4          0000875f48998649     None
hdisk5          000005317c58000e     None
# alt_disk_install -v alt_disk_432   hdisk2
#lspv
hdisk0          00006091aef8b687     rootvg
hdisk1          00000103000d1a78     rootvg
hdisk2          000040445043d9f3     alt_disk_432
hdisk3          00076443210a72ea     alt_disk_432
hdisk4          0000875f48998649     None
hdisk5          000005317c58000e     None

To wake_up an original rootvg, after booting from the new alternate disk:

alt_disk_install -W hdisk0

The following is an example of the output:

# lspv
hdisk0          000040445043d9f3     old_rootvg
hdisk1          00076443210a72ea     rootvg
# alt_disk_install -W hdisk0
# lspv
hdisk0          000040445043d9f3     altinst_rootvg
hdisk1          00076443210a72ea     rootvg

The altinst_rootvg volume group is varied-on and the /alt_inst file systems are mounted.

To put-to-sleep a volume group that had experienced a wake-up:
```
alt_disk_install -S
```
The following is an example of the output
```
# lspv
hdisk0          000040445043d9f3     altinst_rootvg
hdisk1          00076443210a72ea     rootvg
# alt_disk_install -S
# lspv
hdisk0          000040445043d9f3     altinst_rootvg
hdisk1          00076443210a72ea     rootvg
```
The altinst_rootvg is no longer varied-on and the /alt_inst file systems are no longer mounted. If it's necessary for the altinst_rootvg volume group name to be changed back to old_rootvg, this can be done with the -v flag.

Files

Table 6. Files
Item	Description
/usr/sbin/alt_disk_install	Contains the alt_disk_install command