[Work] tracert

Tech talk during some troubleshoot / investigation.... It is something new learnt today though :)


Keeno: Dude i got a tech question u can help??
Tech Dude: shure
Keeno: 1) I am in E// office and hence in E// network
Keeno: 2) I am doing a tracert test to URL removed
Tech Dude: yup
Keeno: 3) What do these results mean?
Keeno: Tracing route to URL removed [ip removed]
over a maximum of 30 hops:
1 43 ms 2 ms 2 ms ip removed
2 1 ms 1 ms 1 ms ip removed
3 1 ms 1 ms 1 ms ip removed
4 12 ms 12 ms 12 ms ip removed
5 136 ms 145 ms 138 ms ip removed
6 134 ms 135 ms 137 ms ip removed
7 136 ms 135 ms 140 ms URL removed [ip removed]
8 144 ms 141 ms 136 ms URL removed [ip removed]
9 139 ms 138 ms 137 ms URL removed [ip removed]
10 140 ms 141 ms 152 ms URL removed [ip removed]
11 138 ms 137 ms 139 ms URL removed [ip removed]
12 143 ms 318 ms 214 ms URL removed [ip removed]
13 289 ms 290 ms 288 ms ip removed
14 294 ms 286 ms 285 ms URL removed [ip removed]
15 342 ms 299 ms 292 ms URL removed [ip removed]
16 278 ms 281 ms 281 ms URL removed [ip removed]
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24 * * * Request timed out.
25 * * * Request timed out.
26 * * * Request timed out.
27 * * * Request timed out.
28 * * * Request timed out.
Keeno: The question is what is happening btw hops 16 and 17
Keeno: coz it says time out, but on the front end, my web portal stuff is still loading...
Tech Dude: URL removed [ip removed] <--- This
Tech Dude: means that there is no reply from the next node
Keeno: if time out, i expect notihng to load at all
Keeno: but i still get page loads
Tech Dude: sometimes, the next node might disable its ICMP replies
Tech Dude: that's why you're not getting anything... but you still can get to the destination
Keeno: so nodes 17 to 28 disabled their replies
Tech Dude: nope
Tech Dude: only node 17
Keeno: and I can safely say I jumped 28 node?
Tech Dude: nope...
Keeno: Coz of node 17, the rest of nodes cannot reply properly?
Tech Dude: yup
Keeno: OK I am a dumbass, educate pls :)
Tech Dude: the chain is broken
Keeno: Ah
Tech Dude: even if 1 link is broken
Keeno: so u won't know if u did jump to the end at Node 17 or theoretically up to Node 30
Tech Dude: well, we are sure that it arrives at node 17 because you get the page loaded
Tech Dude: tracert uses ICMP
Tech Dude: which is different from the typical tcp/ip protocol used by http
Keeno: i mean it stll registers nodes, but does it mean page loads at node 17, or there could be more jumpts we are not aware of (eg: Node 30 could be the real node where the page load actually happens)
Tech Dude: yes...there might be more nodes
Keeno: aha OK
Keeno: so I know the MINUMUM, not the MAXIMUM (which is what I am trying to prove...)
Tech Dude: because tracert dies at #30 if there are no replies
Tech Dude: yup
Keeno: yup tracert is limtied to 30 only
Keeno: is there any other more reliable trace function then?
Keeno: something easy that bodoh punya PM can use?
Tech Dude: hmm... there are applications out there that can be downloaded
Tech Dude: but i've never tried any of em
Keeno: aiya malas and too much trouble :D
Tech Dude: hahaha
Keeno: OK so I will live with tracert then ... thx dude
Tech Dude: sure no probs
Keeno: oh a bit more Q
Keeno: which of the columns do I use to add up showing there is network latency??
Keeno: Eg:
Keeno: 43 ms 2 ms 2 ms ip removed
Keeno: is it 43, 2 or 2?
Tech Dude: those are the replies of 3 separate packets
Tech Dude: the first reply took 43 ms
Tech Dude: the second took 2ms
Tech Dude: the 3rd took 2ms
Tech Dude: a tracert command sends 3 packets for every stop
Tech Dude: it's thus safe to say that the MAXIMUM latency for that IP is 43ms
Tech Dude: this might help a lil...if you're into reading geek stuff - http://www.exit109.com/~jeremy/news/providers/traceroute.html
Keeno: OK so I will add all the items in the first column then
Tech Dude: just use one of the entries...
Tech Dude: it's easier
Tech Dude: i mean...
Tech Dude: tracert does not tell the whole story
Tech Dude: because tracert sends out ICMP
Tech Dude: which is heavy
Tech Dude: compared to HTTP
Tech Dude: http might take less time
Keeno: OK thx
Tech Dude: sure no probs