From 12c onwards, MGMTDB which is known as GRID INFRASTRUCTURE MANAGEMENT REPOSITORY( GIMR) , stores diagnostic and performance related data for GRID infrastructure.
This MGMTDB is created as part of oracle grid installation. However there might be some instances where mgmtdb gets corrupted or requirement is to move the database to another diskgroup, then solution is to drop the mgmtdb and create the same again. Below steps can be followed sequentially to achieve the solution.
ENVIRONMENT -> 2 node 12.1.0.2 GRID setup.(hostdb1-6,hostdb2-6)
GRID_OWNER -> oracle
GRID_HOME -> /gridapp/app/oracle/product/grid12c
MGMT_DISKGROUP -> +MGMT
1. Find on which node mgmt db is running:
MGMT always runs only on one node.
oracle@hostdb1-6:~$ srvctl status mgmtdb Database is enabled Instance -MGMTDB is running on node hostdb1-6
2. Stop and disable CRF component as root user. ( on both the nodes)
-- ON NODE 1: root@hostdb01# echo $ORACLE_HOME /gridapp/app/oracle/product/grid12c root@hostdb1-6:~# cd /gridapp/app/oracle/product/grid12c/bin root@hostdb1-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl stop res ora.crf -init CRS-2673: Attempting to stop 'ora.crf' on 'hostdb1-6' CRS-2677: Stop of 'ora.crf' on 'hostdb1-6' succeeded root@hostdb1-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl modify res ora.crf -attr ENABLED=0 -init -- ON NODE 2: root@hostdb2-6:~# cd /gridapp/app/oracle/product/grid12c/bin root@hostdb2-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl stop res ora.crf -init CRS-2673: Attempting to stop 'ora.crf' on 'hostdb2-6' CRS-2677: Stop of 'ora.crf' on 'hostdb2-6' succeeded root@hostdb2-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl modify res ora.crf -attr ENABLED=0 -init
3. Delete the mgmt db ( from grid owner)
— In our setup grid owner is oracle
oracle@hostdb1-6:~$ cd $ORACLE_HOME/bin oracle@hostdb1-6:...app/oracle/product/grid12c/bin$ dbca -silent -deleteDatabase -sourceDB -MGMTDB Connecting to database 4% complete 9% complete 14% complete 19% complete 23% complete 28% complete 47% complete Updating network configuration files 48% complete 52% complete Deleting instance and datafiles 76% complete 100% complete Look at the log file "/gridapp/app/grid/cfgtoollogs/dbca/_mgmtdb0.log" for further details. oracle@hostdb1-6:...app/oracle/product/grid12c/bin$
4. Now create the NEW MGMT container DB ( ONLY ONE ONE NODE)
dbca -silent -createDatabase -sid -MGMTDB -createAsContainerDatabase true -templateName MGMTSeed_Database.dbc -gdbName _mgmtdb
-storageType ASM -diskGroupName +MGMTDB -datafileJarLocation /gridapp/app/oracle/product/grid12c/assistants/dbca/templates -characterset AL32UTF8 -autoGeneratePasswords -skipUserTemplateCheck
oracle@hostdb1-6:...app/oracle/product/grid12c/bin$ dbca -silent -createDatabase -sid -MGMTDB -createAsContainerDatabase true -templateName MGMTSeed_Database.dbc -gdbName _mgmtdb -storageType ASM -diskGroupName +MGMTDB -datafileJarLocation /gridapp/app/oracle/product/grid12c/assistants/dbca/templates -characterset AL32UTF8 -autoGeneratePasswords -skipUserTemplateCheck Registering database with Oracle Grid Infrastructure 5% complete Copying database files 7% complete 9% complete 16% complete 23% complete 30% complete 37% complete 41% complete Creating and starting Oracle instance 43% complete 48% complete 49% complete 50% complete 55% complete 60% complete 61% complete 64% complete Completing Database Creation 68% complete 79% complete 89% complete 100% complete Look at the log file "/gridapp/app/grid/cfgtoollogs/dbca/_mgmtdb/_mgmtdb4.log" for further details.
5. Now create the NEW MGMT pluggable DB ( ONLY ONE ONE NODE)
dbca -silent -createPluggableDatabase -sourceDB -MGMTDB -pdbName preom -createPDBFrom RMANBACKUP -PDBBackUpfile /gridapp/app/oracle/product/grid12c/assistants/dbca/templates/mgmtseed_pdb.dfb -PDBMetadataFile /gridapp/app/oracle/product/grid12c/assistants/dbca/templates/mgmtseed_pdb.xml -createAsClone true
oracle@hostdb1-6:...app/oracle/product/grid12c/bin$ dbca -silent -createPluggableDatabase -sourceDB -MGMTDB -pdbName preom -createPDBFrom RMANBACKUP -PDBBackUpfile /gridapp/app/oracle/product/grid12c/assistants/dbca/templates/mgmtseed_pdb.dfb -PDBMetadataFile /gridapp/app/oracle/product/grid12c/assistants/dbca/templates/mgmtseed_pdb.xml -createAsClone true [Finalizer] [ 2020-08-13 19:40:10.915 AST ] [ClusterUtil.finalize:117] ClusterUtil: finalized called for oracle.ops.mgmt.has.ClusterUtil@1f248f2b Creating Pluggable Database 4% complete 12% complete 21% complete 38% complete 55% complete 85% complete Completing Pluggable Database Creation 100% complete Look at the log file "/gridapp/app/grid/cfgtoollogs/dbca/_mgmtdb/preom/_mgmtdb2.log" for further details. oracle@hostdb1-6:...app/oracle/product/grid12c/bin$
6. Check the MGMTDB status:
oracle@hostdb1-6:...app/oracle/product/grid12c/bin$ srvctl status mgmtdb Database is enabled Instance -MGMTDB is running on node hostdb1-6
7 . Run the mgmtca config tool: ( only on node node)
oracle@hostdb1-6:...app/oracle/product/grid12c/bin$ which mgmtca /gridapp/app/oracle/product/grid12c/bin/mgmtca oracle@hostdb1-6:...app/oracle/product/grid12c/bin$ mgmtca
8 . Start and enable the CRF component ( ON BOTH NODES)– Run as root user
-- ON NODE 1: root@hostdb1-6:~# cd /gridapp/app/oracle/product/grid12c root@hostdb1-6:/gridapp/app/oracle/product/grid12c# cd bin root@hostdb1-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl modify res ora.crf -attr ENABLED=1 -init root@hostdb1-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl start res ora.crf -init CRS-2672: Attempting to start 'ora.crf' on 'hostdb1-6' CRS-2676: Start of 'ora.crf' on 'hostdb1-6' succeeded -- ON NODE 2: root@hostdb2-6:~# cd /gridapp/app/oracle/product/grid12c root@hostdb2-6:/gridapp/app/oracle/product/grid12c# cd bin root@hostdb2-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl modify res ora.crf -attr ENABLED=1 -init root@hostdb2-6:/gridapp/app/oracle/product/grid12c/bin# ./crsctl start res ora.crf -init CRS-2672: Attempting to start 'ora.crf' on 'hostdb2-6' CRS-2676: Start of 'ora.crf' on 'hostdb2-6' succeeded
9 . Do post check:
oracle@hostdb1-6:~$ export ORACLE_SID=-MGMTDB
oracle@hostdb1-6:~$ s
SQL*Plus: Release 12.1.0.2.0 Production on Thu Aug 13 21:36:41 2020
Copyright (c) 1982, 2014, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, Automatic Storage Management and Advanced Analytics options
SQL> select comp_id,status from dba_registry;
COMP_ID STATUS
------------------------------ --------------------------------------------
OWM VALID
XDB VALID
CATALOG VALID
CATPROC VALID
RAC OPTION OFF
SQL> show pdbs
CON_ID CON_NAME OPEN MODE RESTRICTED
---------- ------------------------------ ---------- ----------
2 PDB$SEED READ ONLY NO
3 PREOM READ WRITE NO
