Basic command UNIX command or script

Posted on 2013-01-31
Last Modified: 2013-01-31
I have a flat file (fileA) with a list of server names. And I have another file (fileB) with a list of server names plus system accounts. I want every line in fileB that its server is not referenced in fileA to be removed. fileB has hundreds of more server names than what is listed in fileA. I need to only have the server names listed in fileA to be in fileB. And of course, do not to change any of the information after the server name in fileB. Please help and let me know if you need me to clarify anything.

Sample of fileA:


Sameple of fileB:

Question by:AIX25
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LVL 12

Expert Comment

ID: 38841784
Hi AIX25,

Are both files already sorted alphanumerically, as they appear to be in the example?
LVL 68

Accepted Solution

woolmilkporc earned 250 total points
ID: 38841788
grep -f fileA fileB > resultfile
LVL 40

Assisted Solution

omarfarid earned 250 total points
ID: 38841794
try this

grep -f fileA fileB > newfile

the file newfile should have the relevant lines you need

Author Closing Comment

ID: 38842016
They were answered minutes of each other. Thank you both!!

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