ORA-01105: mount is incompatible with mounts by other instances ORA-19808: recovery destination parameter mismatch

Please check both db_recovery_file_dest and  db_recovery_file_dest_size parameters . In my case db_recovery_file_dest_size is different . See the below details 


1)Instance 1

SQL> show parameter recovery

NAME                                        TYPE       VALUE
-------------- ---------------------- ----------- ------------------------------
db_recovery_file_dest                      string      +ARCH01_R5
db_recovery_file_dest_size                 big integer  50G

2)Instance 2

SQL> show parameter recovery

NAME                                        TYPE       VALUE
-------------- ---------------------- ----------- ------------------------------
db_recovery_file_dest                      string      +ARCH01_R5
db_recovery_file_dest_size                 big integer  40G

I have Started  the Instance 2 and changed the file_dest_size to 50G

Terminal> srvctl start instance -d DBname -i Instance_name

Terminal> sqlplus /nolog

 SQL>conn / as sysdba

SQL> alter system set db_recovery_file_dest_size =50G scope=both;

Then again i tried to start first instance and it is successfully started.

Terminal>srvctl start instance -d DBname -i Instance_name

Thanks,

Jyothish Balakrishnan