11g rac生产环境异机恢复报错RMAN-6013

今天在客户现场做异机恢复的时候遇到了RMAN-6013报错，具体原因大家请看以下官方文档。
我们什么都不用做，但是要知道问题的原因。

PURPOSE

This is a brief reference note to show the meaning of database error "RMAN-6013". It includes the error text, "Cause" and "Action" from message files for each database version from 9.2 onwards, along with search links and details of any database bug issues related to the error.

SCOPE

This note is intended for general audience as a starting point to check the meaning of "RMAN-6013". It does not give detailed information about the error and does not give error message text for versions below 9.2 .
DETAILS

DETAILS

Error Text, Cause and Action from Message File/s for RMAN-06013

Versions 9.2, 10.1, 10.2, 11.1, 11.2, 12.1

Error:  RMAN-06013 duplicate channel identifier found: %s 
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Cause:  A channel identifier was reused without first releasing the channel. 
Action: Add a RELEASE CHANNEL command. 

Search Links for RMAN-06013

The links below can be used to locate RMAN-6013 in the documentation, and to search for documents that give more information about the error.
Search MOS for "RMAN-06013 Troubleshooting"

Search 12.1 documentation for RMAN-06013
Search 11.2 documentation for RMAN-06013
Search 11.1 documentation for RMAN-06013
Search 10.2 documentation for RMAN-06013
Database Bugs Related to RMAN-06013

Errors are usually due to usage, application or configuration issues but in some cases they may be caused by a bug issue. This section lists any database bugs that have been linked to error "RMAN-6013" .
There are currently no documented database bugs linked to "RMAN-6013" .