traceroute -4 -I -T --port=80 www.google.com 443 MAN NAME traceroute - print the route packets trace to network host SYNOPSIS traceroute [-46dFITUnreAV] [-f first_ttl] [-g gate,...] [-i device] [-m max_ttl] [-p port] [-s src_addr] [-q nqueries] [-N squeries] [-t tos] [-l flow_label] [-w waittimes] [-z sendwait] [-UL] [-D] [-P proto] [--sport=port] [-M method] [-O mod_options] [--mtu] [--back] host [packet_len] traceroute6 [options] tcptraceroute [options] lft [options] --help Print help info and exit. -4, -6 Explicitly force IPv4 or IPv6 tracerouting. By default, the program will try to resolve the name given, and choose the appropriate protocol automatically. If resolving a host name returns both IPv4 and IPv6 addresses, traceroute will use IPv4. -I, --icmp Use ICMP ECHO for probes -T, --tcp Use TCP SYN for probes -d, --debug Enable socket level debugging (when the Linux kernel supports it) -F, --dont-fragment Do not fragment probe packets. (For IPv4 it also sets DF bit, which tells intermediate routers not to fragment remotely as well). Varying the size of the probing packet by the packet_len command line parameter, you can manually obtain infor‐ mation about the MTU of individual network hops. The --mtu option (see below) tries to do this automatically. Note, that non-fragmented features (like -F or --mtu) work properly since the Linux kernel 2.6.22 only. Before that version, IPv6 was always fragmented, IPv4 could use the once the discovered final mtu only (from the route cache), which can be less than the actual mtu of a device. -f first_ttl, --first=first_ttl Specifies with what TTL to start. Defaults to 1. -g gateway, --gateway=gateway Tells traceroute to add an IP source routing option to the outgoing packet that tells the network to route the packet through the specified gateway (most routers have disabled source routing for security reasons). In gen‐ eral, several gateway's is allowed (comma separated). For IPv6, the form of num,addr,addr... is allowed, where num is a route header type (default is type 2). Note the type 0 route header is now deprecated (rfc5095). -i interface, --interface=interface Specifies the interface through which traceroute should send packets. By default, the interface is selected ac‐ cording to the routing table. -m max_ttl, --max-hops=max_ttl Specifies the maximum number of hops (max time-to-live value) traceroute will probe. The default is 30. -N squeries, --sim-queries=squeries Specifies the number of probe packets sent out simultaneously. Sending several probes concurrently can speed up traceroute considerably. The default value is 16. Note that some routers and hosts can use ICMP rate throttling. In such a situation specifying too large number can lead to loss of some responses. -n Do not try to map IP addresses to host names when displaying them. -p port, --port=port For UDP tracing, specifies the destination port base traceroute will use (the destination port number will be incremented by each probe). For ICMP tracing, specifies the initial ICMP sequence value (incremented by each probe too). For TCP and others specifies just the (constant) destination port to connect. When using the tcptraceroute wrap‐ per, -p specifies the source port. -t tos, --tos=tos For IPv4, set the Type of Service (TOS) and Precedence value. Useful values are 16 (low delay) and 8 (high throughput). Note that in order to use some TOS precedence values, you have to be super user. For IPv6, set the Traffic Control value. -l flow_label, --flowlabel=flow_label Use specified flow_label for IPv6 packets. -w max[,here,near], --wait=max[,here,near] Determines how long to wait for a response to a probe. There are three (in general) float values separated by a comma (or a slash). Max specifies the maximum time (in seconds, default 5.0) to wait, in any case. Traditional traceroute implementation always waited whole max seconds for any probe. But if we already have some replies from the same hop, or even from some next hop, we can use the round trip time of such a reply as a hint to determine the actual reasonable amount of time to wait. The optional here (default 3.0) specifies a factor to multiply the round trip time of an already received re‐ sponse from the same hop. The resulting value is used as a timeout for the probe, instead of (but no more than) max. The optional near (default 10.0) specifies a similar factor for a response from some next hop. (The time of the first found result is used in both cases). First, we look for the same hop (of the probe which will be printed first from now). If nothing found, then look for some next hop. If nothing found, use max. If here and/or near have zero values, the corresponding com‐ putation is skipped. Here and near are always set to zero if only max is specified (for compatibility with previous versions). -q nqueries, --queries=nqueries Sets the number of probe packets per hop. The default is 3. -r Bypass the normal routing tables and send directly to a host on an attached network. If the host is not on a directly-attached network, an error is returned. This option can be used to ping a local host through an inter‐ face that has no route through it.