So you have: 

2345      IP   NAME.com         STATUS IPADDRESS1
2345/3213 IP NAME-interfce2.com STATUS IPADDRESS1

[download]
Which you say have the same "ip address".

Okay, so what do you want to do with them?
Do you want to keep one line and throw the other line away?
If so, which one do you want to keep, and why? What are the rules to this game?

If you are indeed wanting to remove "duplicates", then a hash is almost certainly what you need.

Update: I'll take a punt and guess that you want to remove those lines that describe hosts, but not interfaces. If that's the case, then it could be as simple as: 

#!/usr/bin/perl
use strict;
use warnings;

while (<DATA>) {
    next if /^\d{4}\s/; # A million ways to do this, but it depends wh
+at the rest of your data looks like
    print;
}

__DATA__
2345      IP   NAME.com         STATUS IPADDRESS1
2345/1243 IP Name-interface.com STATUS IPADDRESS2
2345/3213 IP NAME-interfce2.com STATUS IPADDRESS1
2345/1212 IP Name-interface3.com STATUS IPADDRESS3
4321      IP   CNAME.com         STATUS IPADDRESS_1
4321/1643 IP CName-interface.com STATUS IPADDRESS_1
4321/3673 IP CNAME-interfce2.com STATUS IPADDRESS_2

[download]
Which would give you: 
2345/1243 IP Name-interface.com STATUS IPADDRESS2
2345/3213 IP NAME-interfce2.com STATUS IPADDRESS1
2345/1212 IP Name-interface3.com STATUS IPADDRESS3
4321/1643 IP CName-interface.com STATUS IPADDRESS_1
4321/3673 IP CNAME-interfce2.com STATUS IPADDRESS_2

[download]
Is that what you are looking for?

Cheers,
Darren

In reply to Re: Multi line matching by McDarren
in thread Multi line matching by imrags

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