How about wrapping it in an eval? 

for ($x=3; $x<255; $x+=2){
    # make new connection
    eval { 
        $ssh = Net::SSH::Perl->new("10.0.0.$x", protocol =>2); 
        $ssh->login($user, $pass);
    };
    next if $@;
}

[download]

Update: Nicer formatting.

In reply to Re: Net::SSH::Perl and handling dead hosts by friedo
in thread Net::SSH::Perl and handling dead hosts by neilwatson

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