"Request timed out " and "destination net unreachable"

[BatchFile]

Can any of you educated types shed any light on a little (and I mean tiny!) networking anomaly for me?

 

Our internet connection was down yesterday (or "the internet's not working" as our users say - "I think you'll find it is, but our connection to it might not be" is my reply, but I digress), caused by a power cut at the next hop along to us. I set a "ping" going, pinging the LEA filters so I'd immediately see when it came back, which looked like the attached picture:

The question is, why do most packets return "request timed out", while one in 10 or so get "reply from 10.105.16.1: destination net unreachable"? 10.105.16.1 is the default gateway and I'm only pinging every second or so - so why are they not all one response or the other?

 

It messes up the statistics as it records the "reply from"s as a recieved packet not a lost one... but that's about as inconvenient as it gets. I've tried messing around with the wait time (/w) but it doesn't seem to make a difference to the ratio of "timed out"s to "reply from"s...

[Steve21]

If I remember right the "net unreachable" is a reply from your last pinged router saying it can't route it.

 

The timeout can be from a routing error or no routes back etc within the time limit.

 

So example if your LEA router sends a ping to it's network and runs out of routers to attempt it'll come back with unreachable, but if it's still trying to route it during the timeout it'll timeout.

 

If that makes any sense? :s

 

Steve

[BatchFile]

That's kind of what I thought; the router's taken it and trying to route it, then when it gives up it sends it back as unreachable... which presumably takes longer than my ping timeout interval most of the time.

 

But if that's all it was wouldn't increasing the /w to 2000 or 4000, instead of the default 1000, mean more unreachables and fewer timeouts? I tried it and It didn't make a noticable difference...

 

Unfortunately (!) the connection's fine again today and I don't really want to unplug it to play with it now as that would be unpopular!