Cause:
I try to drop an asm diskgroup which is not properly created but i get the error that diskgroup is not mounted
SQL> drop diskgroup DATA; drop diskgroup DATA * ERROR at line 1: ORA-15039: diskgroup not dropped ORA-15001: diskgroup "DATA" does not exist or is not mounted
Error code:
[oracle@exdbadm02 ~]$ oerr ora 15039 && oerr ora 15001 15039, 00000, "diskgroup not dropped" // *Cause: An attempt to drop a diskgroup failed. // *Action: See the associated messages for details about why the drop // was not successful. // 15001, 00000, "diskgroup \"%s\" does not exist or is not mounted" // *Cause: An operation failed because the diskgroup specified does not // exist or is not mounted by the current ASM instance. // *Action: Verify that the diskgroup name used is valid, that the // diskgroup exists, and that the diskgroup is mounted by // the current ASM instance. //
When i checked the logfile,i can see couple of errors because the physical disks are removed from the storage tier
ORA-15032: not all alterations performed ORA-15017: diskgroup "DATA" cannot be mounted ORA-15063: ASM discovered an insufficient number of disks for diskgroup "DATA" ERROR: alter diskgroup DATA MOUNT /* ASMCA */ Sat Feb 06 16:58:19 2021 NOTE: No asm libraries found in the system ASM Health Checker found 1 new failures Sat Feb 06 16:59:11 2021 SQL> drop diskgroup DATA ORA-15039: diskgroup not dropped ORA-15001: diskgroup "DATA" does not exist or is not mounted
Workaround:
If graceful drop doesnot work ,then we can forcefully drop the diskgroup with contents option
SQL> drop diskgroup DATA force including contents; Diskgroup dropped.
Oracle forcefully erase the diskgroup header and metadata of the diskgroups
NOTE: Assigning number (2,9) to disk (o/192.168.56.33/DATA_CD_cell19_stocell) NOTE: Assigning number (2,8) to disk (o/192.168.56.33/DATA_CD_cell09_stocell) NOTE: erasing header on grp 2 disk DATA_CD_CELL09_STOCELL NOTE: erasing header on grp 2 disk DATA_CD_CELL19_STOCELL NOTE: Disk DATA_CD_CELL09_STOCELL in mode 0x19 marked for de-assignment NOTE: Disk DATA_CD_CELL19_STOCELL in mode 0x19 marked for de-assignment SUCCESS: diskgroup DATA was force dropped SUCCESS: drop diskgroup DATA force including contents