I used bash sed to replace ip address in a group of files, i.e 10.1.1.x => 10.2.2.x-19:
file1: 10.1.1.29 => 10.2.2.10,
file2: 10.1.1.30 => 10.2.2.11,
file3: 10.1.1.31 => 10.2.2.12,
etc.
I almost managed with:
for file in ifcfg* ; do sed -e "s/10.1.1./10.2.2./" $file >tmp/$file ; done
but couldn't figure out how to calculate and replace the last address position (x => x-19)
it's probably really easy...
Here's one way to do it:
$ for file in ifcfg*; do
num=$(grep IPADDR $file|awk -F. '{print $4}')
sed -e "s/10.1.1.[0-9]\+/10.2.2.$(($num-19))/" $file >tmp/$file
done
This takes the contents of the IP address and cut's it down so that it's the 4th octet, which is stored in the variable $num. This variable is then added with 19 during the sed command. I needed to expand your original sed a bit by adding a [0-9]\+ to remove the existing 4th octet so that we could just replace it with $num+19.
/etc/sysconfig/network-scripts/ifcfg*?
– slm♦
Jul 2 '13 at 15:23
You will have better luck doing this with awk rather than sed.
awk -F. '{printf ("%d.%d.%d.%d\n",$1,$2,$3,$NF-19)}'
or as per your example,
awk -F. '/10.1.1/ {printf ("10.2.2.%d\n",$1,$2,$3,$NF-19)}'
or
for file in ifcfg*
do
awk -F. '/10.1.1/ {printf ("10.2.2.%d\n",$1,$2,$3,$NF-19)}' $file >tmp/$file
done
To preserve the other lines and assuming that x is the last element on the line to be replaced, here is what you do
for file in ifcfg*
do
awk -F. '/10.1.1/ {printf ("%s.%d.%d.%d\n",$1,2,2,$NF-19)}
!/10.1.1/ {print $0}' $file > tmp/$file
done
awk 'BEGIN{FS=OFS="."} {$NF -= 19; print $0 > ("tmp/" FILENAME)}' ifcfg*
I'd use perl for this:
$ grep '10\.' file[123]
file1:10.1.1.29
file2:10.1.1.30
file3:10.1.1.31
$ perl -i -pe 's/10\.1\.1\.(\d+)/ "10.2.2." . ($1 - 19) /ge' file[123]
$ grep '10\.' file[123]
file1:10.2.2.10
file2:10.2.2.11
file3:10.2.2.12
