ORA-38777: database must not be started in any other instance

 

I have 19c DB converted to SNAPSHOT STANDBY and now i wanted to revert back to Physical standby

SQL> select NAME, OPEN_MODE, GUARD_STATUS, DATABASE_ROLE from v$database;

NAME      OPEN_MODE            GUARD_S DATABASE_ROLE
--------- -------------------- ------- ----------------
MYPROD    READ WRITE           NONE    SNAPSHOT STANDBY

While Converting Snapshot standby back to Physical standby while both RAC Nodes are up and running we get this error

SQL> ALTER DATABASE CONVERT TO PHYSICAL STANDBY;

ALTER DATABASE CONVERT TO PHYSICAL STANDBY

*

ERROR at line 1:

ORA-38777: database must not be started in any other instance

srvctl status database -d myprod_std -v
Instance myprod_std1 is running on node hostname1. Instance status: Mounted (Closed).
Instance myprod_std2 is running on node hostname2. Instance status: Mounted (Closed).

NOTE : 

   Instance should open in only 1 node to Convert back

 $ srvctl stop instance -i myprod2 -d myprod_std
 
hostname:myprod1:/export/scripts $ sqlplus / as sysdba
 
SQL*Plus: Release 19.0.0.0.0 - Production on Fri Jun 9 13:11:19 2023
Version 19.17.0.0.0
 
Copyright (c) 1982, 2022, Oracle.  All rights reserved.
 
 
Connected to:
Oracle Database 19c EE Extreme Perf Release 19.0.0.0.0 - Production
Version 19.17.0.0.0
 
SQL> ALTER DATABASE CONVERT TO PHYSICAL STANDBY;
 
Database altered.
 
SQL> shut immediate
ORA-01109: database not open
 
 
Database dismounted.
ORACLE instance shut down.
SQL> exit
 
$ srvctl start database -d myprod_std -v
 
$ srvctl status database -d myprod_std -v

Instance myprod_std1 is running on node hostname1. Instance status: Mounted (Closed).

Instance myprod_std2 is running on node hostname2. Instance status: Mounted (Closed).

 
hostname:myprod_std:/export/scripts $ sqlplus / as sysdba
 
SQL*Plus: Release 19.0.0.0.0 - Production on Fri Jun 9 13:13:41 2023
Version 19.17.0.0.0
 
Copyright (c) 1982, 2022, Oracle.  All rights reserved.
 
 
Connected to:
Oracle Database 19c EE Extreme Perf Release 19.0.0.0.0 - Production
Version 19.17.0.0.0
 
SQL> alter database open;
 
Database altered.
 
SQL> select NAME, OPEN_MODE, GUARD_STATUS, DATABASE_ROLE from v$database;
 
NAME      OPEN_MODE            GUARD_S  DATABASE_ROLE
--------- -------------------- ------- ----------------
MYPROD    READ ONLY            NONE     PHYSICAL STANDBY
 
 Start MRP .......

SQL> alter database recover managed standby database disconnect from session;
 
Database altered.