6.1. Troubleshooting Diagnostics
If a command is not working as expected, you can gather diagnostics in the following ways:
Use the -v, -vv, -vvv, or -vvvv argument of any command for increasingly verbose levels of output.
If the problem is related to the logical volume activation, set 'activation = 1' in the 'log' section of the configuration file and run the command with the -vvvv argument. After you have finished examining this output be sure to reset this parameter to 0, to avoid possible problems with the machine locking during low memory situations.
Run the lvmdump command, which provides and information dump for diagnostic purposes. For information, see the lvmdump(8) man page.
Execute the lvs -v, pvs -a or dmsetup info -c command for additional system information.
Examine the last backup of the metadata in the /etc/lvm/backup file and archived versions in the /etc/lvm/archive file.
Check the current configuration information by running the lvm dumpconfig command.
Check the .cache file in the /etc/lvm directory for a record of which devices have physical volumes on them.