RMAN-06900 RMAN-06901 ORA-19921: maximum number of 64 rows exceeded

Problem Description
RMAN backup completed successfully but backup logs shows warning message as,
RMAN-06900: WARNING: unable to generate V$RMAN_STATUS or V$RMAN_OUTPUT row
RMAN-06901: WARNING: disabling update of the V$RMAN_STATUS and V$RMAN_OUTPUT rows ORACLE error from target database:
ORA-19921: maximum number of 64 rows exceeded

A variant version of warning message is like below,

connected to target database: PROD1 (DBID=3378321056)
RMAN-06900: WARNING: unable to generate V$RMAN_STATUS or V$RMAN_OUTPUT row
RMAN-06901: WARNING: disabling update of the V$RMAN_STATUS and V$RMAN_OUTPUT rows
ORACLE error from target database:
ORA-19921: maximum number of 128 rows exceeded

Cause of the Problem
The RMAN-06900 RMAN-06901 ORA-19921 error stack indicates oracle RMAN bug. ORA-19921: maximum number of 64 rows exceeded is oracle bug 4659734 and ORA-19921: MAXIMUM NUMBER OF 128 ROWS EXCEEDED is oracle Bug 8264365. This bug fires when the RMAN output is too huge because it couldn't log the output in v$rman_output.

Solution of the Problem
If your RMAN goes well and you only see warning message in your RMAN log then simply you can ignore these warnings. The bug "ORA-19921: maximum number of 64 rows exceeded" is fixed in Oracle 10.2.0.4 version and in 11g. So to solve it upgrade your oracle version or apply oracle patch. If you already have oracle version 10.2.0.4 + and hit this bug then in fact you should do nothing and just to wait for oracle to resolve the issue.

Related Documents
http://arjudba.blogspot.com/2010/01/rman-00571-rman-00569-rman-00571-rman.html
http://arjudba.blogspot.com/2010/01/rman-06900-rman-06901-ora-19921-maximum.html