I'm wondering to check my gateway with nmap. And for nmap --traceroute -sS IPADDR -P0 -p80 I've got no address.
What does it mean and how can I got info about the host ?
Thanks in advance!
UPDATE: Exact output of nmap follows.
TRACEROUTE (using proto 1/icmp)
HOP RTT ADDRESS
1 ... 30
The empty field is below ADDRESS.
This means, that no hop between you and target host replied with Time-to-live exceeded ICMP message to traceroute probe. Since you used --traceroute nmap output is very similar to the traceroute output.
1 ... 30 means that you haven't received any response to 30 probes, and by default traceroute (and nmap) gives up after 30 hops.
This means that either host is down, or you have ICMP messages blocked on your firewall or on all intermediate router between you and a taget. Try tracerouting existing hosts and see if it's the case. The second part of your question is a bit vague, please be more specific on what kind of info you want to get.
Citing @Ladadadada from this Server Fault question "what does “***” mean when traceroute"
Traceoute requires a response from the target server and each of the intermediate hops to create its output. If a router doesn't generate a Time-to-live exceeded response, traceroute will not know anything about that hop. A hop that outputs * * * means that the router at that hop doesn't respond to the type of packet you were using for the traceroute (by default it's UDP on Unix-like and ICMP on Windows).