bash Shell script to modify DNS zone file

KinnowGrower · 12-10-2009, 09:37 PM

hello everybody

i am writing a bash shell script to modify the DNS zone file. I have completed many steps, but i am stuck at the point given below.

The problem is to write a shell script/command to Convert all CNAMEs that are referencing the same domain to A records:

ie:

Code:

                               IN      A       66.223.38.187
               ftp             IN      CNAME   my-site.com.
               web             IN      CNAME   my-site.com.

     to

               ftp             IN      A       66.223.38.187
               web             IN      A       66.223.38.187

I have tried all the ways i.e. google and other Sed/awk tutorial.But could not find the solution.

datopdog · 12-11-2009, 02:18 AM

Why not use perl ? http://search.cpan.org/~mschilli/DNS...S/ZoneParse.pm

KinnowGrower · 12-12-2009, 12:26 PM

thanks for reply. you are right, But its requirement to do it in bash only. can any body help please?

urban.yoga.journeys · 12-12-2009, 03:47 PM

Code:

#!/bin/bash


match=0
check=0
#put all re-occurring patterns in array "patterns"
patterns=($(awk '{print $4}' your_file_here | uniq -d))

#will read input file line by line
while read line; do
	#will check current line for every pattern in the array
	for item in ${patterns[@]}; do
		echo $line | grep -q $item
		#if there is a match, "match"=1 and replacement of CNAME will take place. "check"=1. "match" is reset to 0. line is printed to temp file
		[ $? == 0 ] && match=1
		if [ $match == 1 ]; then
			echo "$line" | sed 's/CNAME/A/' >> cname.temp
			check=1
			match=0
		fi
	done
	#if "check"=0 (no match was found), print line without modification to temp file
	[ $check = 0 ] && echo "$line" >> cname.temp
	check=0
done < your_file_here

#rename temp file to input file
mv cname.temp your_file_here

KinnowGrower · 12-12-2009, 08:07 PM

Wao! Thanks for help

I think it is what i am in need of.

Thanks