SiMPLE | Forum

THRILLHO

Player

Reputation: +1

Registered: 2015-10-25

Posts: 3

Tracert Hop Timeout

This doesn't appear to be a very serious issue, but when I cmd tracert TGE server IP,  I get a timeout on hop 10 every time. I don't believe it's a problem on my end, and I have been able to connect for years without incident, but I'm just curious about it. If anyone knows anything about this and could give me some insight, it would be greatly appreciated. Cheers,

THRILLHO

ABAS

disciple of Jeff

Reputation: +1961

Registered: 2015-12-10

Posts: 2,325

Website

Re: Tracert Hop Timeout

Some routes /hops do not answer back that "echo" command you ask them

Last edited by ABAS (2018-08-12 21:37:13)

Trench

Member

Reputation: +129

Registered: 2014-05-05

Posts: 221

Re: Tracert Hop Timeout

Like ABAS already indicated, seeing "no response" / timeout from traceroute just means that particular "hop" (router) is either configured not to respond to ICMP Echo requests, or the router has de-prioritized them under significant load in order to keep up with higher-priority traffic.

If you're seeing other routers after the non-responsive one it's usually no big deal, and you're just missing a piece of the picture from within the middle of the route.  But when the non-responsive router(s) also happen to be the last hop(s) in the route, this creates a condition where traceroute cannot determine if or where the route actually ended.  And so the traceroute just blindly continues on for the maximum 30 or however many hops it's configured to try before giving up.

It's the same underlying condition in both cases (no response to the ICMP Echo), and simply "because it occurred on the last hop(s)" that creates the "can't tell where this route ends" condition.  The ICMP Echo sent to the last router(s) don't receive a response because of the configuration on the routers themselves, but then traceroute's attempt to send an ICMP Echo to the next router(s) beyond the non-responsive router also fails (and is also shown as non-responsive) because no further router actually exists.  Traceroute has to continue because he cannot predict whether the router he's trying to reach is non-responsive intentionally, or non-responsive because it simply doesn't exist at all.

THRILLHO

Player

Reputation: +1

Registered: 2015-10-25

Posts: 3

Re: Tracert Hop Timeout

Thank you Trench, for your comprehensive and enlightening explanation. And thank you ABAS, for giving a conceivable, albeit more succinct answer as well. The swiftness of your responses is also very helpful, soldiers. Cheers,

-THRILLHO