ORA-00230: operation disallowed: snapshot control file enqueue unavailable

This error encountered during archivelog backup of a database. More details of error below: Starting backup at 27-APR-15 channel CH01: starting full datafile backup set channel CH01: specifying datafile(s) in backup set waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue waiting for snapshot control file enqueue cannot make a snapshot control file released channel: CH01 released channel: CH02 RMAN-00571: =========================================================== RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS =============== RMAN-00571: =========================================================== RMAN-03009: failure of backup command on CH01 channel at 04/27/2015 04:00:14 ORA-00230: operation disallowed: snapshot control file enqueue unavailable Cause: One process is holding an enqueue on the control file when this backup attempt was made. Two options are: 1. Wait for the enqueue holding session/process to complete. 2. Locate and terminate the holder if you can afford to. For option 2. Use the sql below to locate the process: SELECT s.sid, username, program, module, action, logon_time, l.* FROM v$session s, v$enqueue_lock l WHERE l.sid = s.sid and l.type = 'CF' AND l.id1 = 0 and l.id2 = 2; You can use operating system "kill -9" command to terminate the identified process and then re-initiate the backup. For windows, use "orakill" utility to terminate the specific thread. orakill sid thread_id sid: instance ID. thread_id: SPID from above. reference: http://www.arcserve-knowledgebase.com