What have you tried? The following may be what you want:

use strict;
use warnings;

my $lastIP;

while (<DATA>) {
  print if /network name|interface name|VRID|state|primary address/i;
  print "$lastIP\n\n" if /Monitored circuits:/ and defined $lastIP;
  $lastIP = $1 if /((\d{1,3}\.){3}\d{1,3})/;
}

[download]
__DATA__
Network name A
Interface WEB_A
    ggggggggg
        VRID 145
        State:        Master    
                   XXXXXXXXXXXX
    Effective  Priority:    200
        07:09:56:04:0t:ef
        Primary address:    194.551.205.250
        Number addresses:    1
        135.51.045.242
Monitored circuits:
            vbgghdfgdfg
Interface WEB_B
    ggggggggg
    Agggggg
    VRID 145
        State:        backup    
                   XXXXXXXXXXXX
    Effective  Priority:    200
        07:09:56:04:0t:ef
        Primary address:    19.51.205.20
        Next advertisement:    0
        Number addresses:    1
            135.51.05.22
        Monitored circuits:
            vbgghdfgdfg

[download]

Prints:

Network name A
        VRID 145
        State:        Master    
        Primary address:    194.551.205.250
135.51.045.242

    VRID 145
        State:        backup    
        Primary address:    19.51.205.20
135.51.05.22

[download]
DWIM is Perl's answer to Gödel

In reply to Re: just another search program by GrandFather
in thread just another search program by sunny

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