This appendix contains information about Solaris Volume Manager files for reference purposes. This appendix contains the following:
This section explains the files that are necessary for Solaris Volume Manager to operate correctly. With the exception of a few specialized configuration changes, you do not need to access or modify these files.
Do not edit this file. If you change this file, you could corrupt your Solaris Volume Manager configuration.
The /etc/lvm/mddb.cf file records the locations of state database replicas. When state database replica locations change, Solaris Volume Manager makes an entry in the mddb.cf file that records the locations of all state databases. See the mddb.cf(4) man page for more information.
The /etc/lvm/md.cf file contains automatically generated configuration information for the default (unspecified or local) disk set. When you change the Solaris Volume Manager configuration, Solaris Volume Manager automatically updates the md.cf file (except for information about hot spares in use). See the md.cf(4) man page for more information.
Do not edit this file. If you change this file, you could corrupt or be unable to recover your Solaris Volume Manager configuration.
If your system loses the information that is maintained in the state database, and as long as no volumes were changed or created in the meantime, you can use the md.cf file to recover your configuration. See How to Initialize Solaris Volume Manager From a Configuration File.
The md.conf configuration file is read by Solaris Volume Manager at startup. The md.conf file contains the state database replica configuration information. As of Solaris 10, the nmd and md_nsets parameters are no longer edited manually. Solaris Volume Manager has been enhanced to configure volumes dynamically, as needed.
The /etc/lvm/md.tab file contains Solaris Volume Manager configuration information that can be used to reconstruct your Solaris Volume Manager configuration. Solaris Volume Manager can use this file as input to the command-line utilities metainit, metadb, and metahs to reconstruct a configuration. Volumes, disk sets, and hot spare pools might have entries in this file. See How to Create Configuration Files for instructions on creating this file (by using the metastat -p > /etc/lvm/md.tab command).
The configuration information in the /etc/lvm/md.tab file might differ from the current volumes, hot spares, and state database replicas in use. This file is used manually, by the system administrator, to capture the intended configuration. After you change your Solaris Volume Manager configuration, recreate this file and preserve a backup copy.
Once you have created and updated the file, the metainit, metahs, and metadb commands then activate the volumes, hot spare pools, and state database replicas defined in the file.
In the /etc/lvm/md.tab file, one complete configuration entry for a single volume appears on each line using the syntax of the metainit, metadb, and metahs commands.
If you use the metainit -an command to simulate initializing all of the volumes in the md.tab file, you might see error messages for volumes that have dependencies on other volumes defined in md.tab. These error messages occur because Solaris Volume Manager does not maintain state of the volumes that would have been created when running metainit -an. Each line is evaluated based on the existing configuration, if a configuration exists. Therefore, even if it appears that the metainit -an command would fail, it might succeed without the -n option.
You then run the metainit command with either the -a option, to activate all volumes in the /etc/lvm/md.tab file, or with the volume name that corresponds to a specific entry in the file.
Solaris Volume Manager does not write to or store configuration information in the /etc/lvm/md.tab file. You must manually edit the file and run the metainit, metahs, or metadb commands to create Solaris Volume Manager components.
For more information, see the md.tab(4) man page.