A Preinstallation Tasks for Systems Running LSM, LVM, Prestoserve, and AdvFS

Perform the preinstallation tasks described in this appendix if you are planning a full installation to Digital UNIX Version 4.0 and your system is using one or more of the following software products:

Logical Storage Manager (LSM)
Logical Volume Manager (LVM)
Prestoserve
Advanced File System (AdvFS)

A.1 Preparing for a Full Installation if Using LSM

Read this section only if your system is installed with and using the Logical Storage Manager (LSM) and you are performing a full installation.

The following steps should be performed to preserve the LSM configuration currently in use on a system. Steps 2 and 4 are not necessary when performing an update installation because the update preserves the LSM volboot file in the root file system.

Check the /etc/vol/volboot file to ensure that it contains valid LSM disks. Enter the following command to list the current disks in /etc/vol/volboot

# voldctl list
Create a backup copy of the /etc/vol/volboot file. The backup copy of /etc/vol/volboot must be restored after the installation is complete. The backup copy should be created on a separate file system that is not located in either the root, /usr, or /var file systems because a full installation destroys (overwrites) those three file systems. In the following example, /backup is a separate file system:

# mkdir /backup/lsm # cp /etc/vol/volboot /backup/lsm/volboot
If the root file system and primary swap device were encapsulated to use LSM volumes rootvol and swapvol respectively, the volumes rootvol and swapvol should be removed before a full installation. If the /usr and /var file systems were encapsulated to LSM volumes, they also should be removed from the LSM configuration before a full installation. Unencapsulating volumes used for root, swap, /usr and /var is not necessary for update installations.
Consider the following LSM configuration with mirrored rootvol and swapvol. The /usr file system is also encapsulated to use the LSM volume volrz10g:
```
v  rootvol    root       ENABLED  ACTIVE  131072  ROUND   -
pl rootvol-01 rootvol    ENABLED  ACTIVE  131072  CONCAT  -         RW
sd rz10-01    rootvol-01 0        131056  16      rz10       rz10
sd rz10-02    rootvol-01 16       0       131056  rz10       rz10
pl rootvol-02 rootvol    ENABLED  ACTIVE  131072  CONCAT  -         RW
sd rz14-01    rootvol-02 0        131056  16      rz14       rz14
sd rz14-02    rootvol-02 16       0       131056  rz14       rz14

 

v  swapvol    swap       ENABLED  ACTIVE  400880  ROUND
pl swapvol-01 swapvol    ENABLED  ACTIVE  400880  CONCAT  -         RW
sd rz10b-01   swapvol-01 0        0       400880  rz10b      rz10b
pl swapvol-02 swapvol    ENABLED  ACTIVE  400880  CONCAT  -         RW
sd rz14b-01   swapvol-02 0        0       400880  rz14b      rz14b

 

v  volusr    fsgen       ENABLED  ACTIVE   1787904  SELECT   -
pl volusr-01 volusr      ENABLED  ACTIVE   1787904  CONCAT -      RW
sd advfs_rz10g-01 volrz10g-01  0     0     1787904 advfs_rz10g rz10g
pl volusr-02 volusr     ENABLED  ACTIVE    1787904  CONCAT -      RW
sd advfs_rz14g-01 volrz10g-02  0     0     1787904 advfs_rz14g  rz14g
```
Perform the following steps to remove the use of the LSM volumes for root, swap, and /usr:
1. Disassociate the second plex in rootvol and swapvol and remove them from the LSM configuration. In this example, the full installation will later be done on rz10:
  # volplex dis rootvol-02 # volplex dis swapvol-02 # voledit -rf rm rootvol-02 swapvol-02 # voldg rmdisk rz14 rz14b # voldisk rm rz14 rz14b
2. Execute the /usr/sbin/volunroot command to unencapsulate rootvol and swapvol. This requires a system reboot for the changes to take effect:
  # /usr/sbin/volunroot
  
  Reboot the system at the next available opportunity.
3. To remove the volumes used for /usr and /var, shut down the system to single-user mode and ensure that the /usr and /var file systems are unmounted. In the previous example, volume volrz10g was used for the /usr file system in the AdvFS domain usr_domain.
  Remove the LSM volume volusr from the LSM configuration:
  # voledit -rf rm volusr # voldg rmdisk advfs_rz10g advfs_rz14g # voldisk rm rz10g rz14g
  
  Change the /etc/fdmns/usr_domain directory to use /dev/rz10g instead of the LSM volume:
  # cd /etc/fdmns/usr_domain # rm volusr # ln -s /dev/rz10g rz10g
  
  If UNIX file systems (UFS) were used instead of Advanced File Systems (AdvFS), the /etc/fstab file should be modified to use /dev/rz10g for the /usr file system.
  Similar steps for the /var file system are required if LSM volumes were used.
Save the current LSM configuration information for added safety. Create a backup copy of the current LSM configuration. The backup copy should be created on a separate file system that is not located in either the root, /usr, or /var file systems because a full installation destroys (overwrites) those three file systems. In the following example, /backup is a separate file system:
1. Save information regarding the disks currently being used with LSM:
  
  # voldisk list > /backup/lsm/voldisk.out
2. Save the LSM diskgroup configuration. For example, enter the following command for each LSM diskgroup in the configuration. The backslashes (\) in the following two command lines indicate line continuation and should not be included in the actual command line:
  
  # volprint -g rootdg -mvps > \ /backup/lsm/volprint.rootdg.out
  
  # volprint -g diskgroup -mvps > \ /backup/lsm/volprint. diskgroup .out
  
  The backup files created in the previous steps should also be copied to a backup media (i.e., tape) before the installation is started for added safety. These configuration files do not need to be restored under normal circumstances; restoring the /etc/vol/volboot file from backup has sufficient information for the LSM configuration.
Perform the installation process as documented in this guide.
After the full installation is complete, restore the backed copies of the LSM volboot file before starting LSM. For example, while in multiuser mode, enter commands similar to the following:

# cp /backup/lsm/volboot /etc/vol/volboot # volinstall # rm -f /etc/vol/reconfig.d/state.d/install-db # vol-startup

After the full installation, the /usr and /var file systems reside on disk partitions. Separate steps are required to encapsulate the disk partitions to LSM volumes. Before the current /usr and /var file systems can be encapsulated to LSM volumes, a cleanup of the LSM configuration that existed before the full installation has to be done. If either the /usr or /var file systems resided on LSM volumes before the full installation, you will have to clean up these LSM volumes because the LSM volumes will no longer be in use.

Refer to Logical Storage Manager for more information about LSM.

A.2 Preparing for a Full Installation if Using LVM

Read this section only if your system is installed with and using the Logical Volume Manager (LVM) and you are performing a full installation.

Note
As announced in a previous release, LVM has been retired beginning with Digital UNIX Version 4.0. LVM is being replaced with the Logical Storage Manager (LSM).

The following steps should be performed to preserve the LVM configuration currently in use on a system:

Create a backup copy of the LVM configuration. The backup copy should be created on a separate file system that is not located in either the root /usr or /var file systems because a full installation destroys (overwrites) those three file systems. In the following example, /backup is a separate file system:
# mkdir /backup/lvm # cp /etc/lvmtab /backup/lvm/lvmtab
Save the special device files associated with LVM volumes by creating a tar file of the special device files. For each LVM volume group on the system, create a tar file of all the special device files in /dev/volume_group. In the following example, vg1, vg2, and vg3 are the volume groups:
# tar cf /backup/lvm/lvm.devfiles.tar /dev/vg1 /dev/vg2 /dev/vg3
Save the current LVM configuration for added safety as shown in the following steps:
1. For each LVM volume group in the configuration, enter the following command to back up the volume group information. In this example, vg1 is the volume group:
  # vgdisplay -v /dev/vg1 > /backup/lvm/vg1.out
2. For each logical volume in a volume group, execute the following command to back up the configuration information. In this example, lvoll is the logical volume and vg1 is the volume group:
  # lvdisplay -v /dev/vg1/lvol1 > /backup/lvm/vg1.lvol1.out
3. For each physical volume in a volume group, execute the following command to back up the configuration information for each physical volume in the volume group. In this example, /dev/rz8c is the physical volume:
  # pvdisplay -v /dev/rz8c > /backup/lvm/vg1.rz8c.out
Perform the full installation of Digital UNIX as described in this guide.
After the full installation is complete, restore the copy of /etc/lvmtab from the backup media as shown in this example:
# cp /backup/lvm/lvmtab /etc/lvmtab

Then, recreate the LVM special device files from the tar file stored in the /backup directory:
# tar xf /backup/lvm/lvm.devfiles.tar

Restoring the /etc/lvmtab file has sufficient information for a complete LVM configuration. The LVM configuration files that were backed up in Step 3 were backed for added safety and do not have to be restored.

Refer to Logical Storage Manager for information about encapsulating existing LVM volumes to LSM volumes.

A.3 Preparing for a Full Installation if Using Prestoserve

Read this section only if your system is using Prestoserve and you are performing a full installation.

You must save your current Prestoserve configuration before beginning a full installation because the root file system is overwritten during a full installation. To save and restore the Prestoserve configuration, follow these steps:

Create a backup copy of the /etc/prestotab file. The backup copy should be created on a separate file system that is not located in either the root, /usr, or /var file systems because a full installation destroys (overwrites) those three file systems. In the following example, /backup is a separate file system:
# mkdir /backup/presto # cp /etc/prestotab /backup/presto/prestotab
Perform the full installation of Digital UNIX as described in this guide.
After the full installation is complete, restore the copy of /etc/prestotab from the backup as shown in this example:
# cp /backup/presto/prestotab /etc/prestotab

To configure the prestoserve software, refer to the prestosetup(8) or setup(8) reference pages for more information.

A.4 Preparing for a Full Installation if Using AdvFS

If your system is configured with AdvFS, a full installation overwrites the /etc/fdmns directory resulting in the loss of critical configuration data. Save a copy of the /etc/fdmns directory and all files under the directory before beginning the installation. After the installation is complete, restore the directory.