Rman's "Rman:can ' t open target" error

On Linux, after the installation is complete, you may experience the following error when testing Rman:

[Oracle@smsdbrac1 oracle]$ Rman Target/
Rman:can ' t open target
This is due to the invocation of the non-Oracle Rman:
[Oracle@smsdbrac1 oracle]$ which Rman
/usr/x11r6/bin/rman

Error and resolution Demo:

[Oracle@rac1 ~]$ Rman Target/
Rman:can ' t open target
[Oracle@rac1 ~]$ which Rman
/usr/x11r6/bin/rman
[Oracle@rac1 ~]$./rman-help
-bash:./rman:no such file or directory
[Oracle@rac1 ~]$ Echo $PATH
/usr/kerberos/bin:/usr/local/bin:/bin:/usr/bin:/usr/x11r6/bin:/home/oracle/bin:/u01/app/oracle/product/10.2.0/ Db_1/bin
[oracle@rac1 ~]$ export path= $ORACLE _home/bin: $PATH:/usr/bin:/bin:/usr/bin/x11:/usr/local/bin (workaround)

Ps:export command: Sets or displays environment variables.
Export, you pass the environment variable you set to the current Shell's child shell so that it works in the child shell

cannot be written in export capitalization, otherwise wrong.
[Oracle@rac1 ~]$ Echo $PATH
/u01/app/oracle/product/10.2.0/db_1/bin:/usr/kerberos/bin:/usr/local/bin:/bin:/usr/bin:/usr/x11r6/bin:/home/ Oracle/bin:/u01/app/oracle/product/10.2.0/db_1/bin:/usr/bin:/bin:/usr/bin/x11:/usr/local/bin
[Oracle@rac1 ~]$ Rman Target/

Recovery manager:release 10.2.0.1.0-production on Tue Oct 16 19:40:25 2012

Copyright (c) 1982, +, Oracle. All rights reserved.

Connected to target DATABASE:ORCL (dbid=1323829629)

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