25.21. Troubleshooting Online Storage Configuration
25.21. Troubleshooting Online Storage Configuration This section provides solution to common problems users experience during online storage reconfiguration. Logical unit removal status is not reflected on the host. When a logical unit is deleted on a configured filer, the change is not reflected on the host. In such cases, lvm commands will hang indefinitely when dm-multipath is used, as the logical unit has now become stale . To work around this, perform the following procedure: Procedure 25.17. Working Around Stale Logical Units Determine which mpath link entries in /etc/lvm/cache/.cache are specific to the stale logical unit. To do this, run the following command: Example 25.16. Determine Specific mpath Link Entries For example, if stale-logical-unit is 3600d0230003414f30000203a7bc41a00, the following results may appear: This means that 3600d0230003414f30000203a7bc41a00 is mapped to two mpath links: dm-4 and dm-5 . , open /etc/lvm/cache/.cache . Delete all lines containing stale-logical-unit and the mpath links that stale-logical-unit maps to. Example 25.17. Delete Relevant Lines Using the same example in the step, the lines you need to delete are:
ls -l /dev/mpath | grep stale-logical-unit lrwxrwxrwx 1 root root 7 Aug 2 10:33 /3600d0230003414f30000203a7bc41a00 -> ../dm-4 lrwxrwxrwx 1 root root 7 Aug 2 10:33 /3600d0230003414f30000203a7bc41a00p1 -> ../dm-5 /dev/dm-4 /dev/dm-5 /dev/mapper/3600d0230003414f30000203a7bc41a00 /dev/mapper/3600d0230003414f30000203a7bc41a00p1 /dev/mpath/3600d0230003414f30000203a7bc41a00 /dev/mpath/3600d0230003414f30000203a7bc41a00p1