rman: can't open target

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## Error
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 [/usr/oracle/siod/SCRIPTS] oracle@host01 $ rman target /
rman: can't open target

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#  Error Occurred
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Error occured while tried to connect rman in one of our server

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## Command Executed
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rman target /

**************************************** Step By Step Analysis ******************************************************

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# 1) Check Home
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I have cross checked whether correct Oracle Database Home and Environmental variable like PATH is correctly set. Everything is fine but still it produces error.

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# 2) Reason for Failure
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Upon Digging Further, found that whenever i type rman its not taking the binary from $ORACLE_HOME/bin

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# 3) Troubleshooting
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I need to find out which rman binary is getting kick started when i give rman target /

So i have given which rman command.

$ which rman
/usr/X11R6/bin/rman

From the above output we can see that whenever i type rman it tries to execute the binary from /usr/X11R6/bin/rman and not $ORACLE_HOME/bin/rman

And also checking the PATH environmental variable,

 /usr/oracle/product/11.2.0.2/bin] oracle@host01 $ echo $PATH
/usr/local/bin:/usr/local/bin:/usr/bin:/usr/X11R6/bin:/bin:/usr/games:/opt/gnome/bin:/opt/kde3/bin:/usr/lib/jvm/jre/bin:/siod/thishost/unix/bin:/usr/lib/mit/bin:/usr/lib/mit/sbin:.:/usr/oracle/product/11.2.0.2/bin
[/usr/oracle/product/11.2.0.2/bin] oracle@host01 $

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## Solution
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Three Solutions available for this Issue.

1) Run the rman prompt like below,

$ORACLE_HOME/bin/rman target /

2) Place $ORACLE_HOME/bin in the beginning of the PATH variable, such that when rman binary is searched it will look into $ORACLE_HOME/bin/rman

3) Remove /usr/X11R6/bin entry from $PATH

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Thanks to my Wife for bringing up this error and helped me in troubleshooting & Resolving.
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 Comments Are Always welcome
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