From: James Keane (jameskeane@yahoo.com)
Date: Fri Aug 12 2005 - 00:34:15 GMT-3
--- James Keane <jameskeane@yahoo.com> wrote:
> --- gladston@br.ibm.com wrote:
>
> > Trying to understand these results. Any help
> > appreciated.
> >
> > Rack2R6#trac 148.5.135.13 (serial of bb2)
> >
> > Type escape sequence to abort.
> > Tracing the route to 148.5.135.13
> >
> > 1 148.5.226.2 4 msec 4 msec 4 msec
> > 2 148.5.235.5 16 msec 16 msec 16 msec
> > 3 *
> > 148.5.135.13 24 msec *
> >
> > Isn't that * on third line strange?
> >
> >
> > Debug ip icmp on bb2:
> >
> > .Feb 28 21:21:57: ICMP: time exceeded rcvd from
> > 148.5.235.5
> > .Feb 28 21:21:57: ICMP: time exceeded rcvd from
> > 148.5.235.5 *
> >
> >
> > I expected something like this:
> >
> > Rack2R6#tra 150.100.1.254
> >
> > 1 148.5.146.4 4 msec
> > 2 148.5.14.1 20 msec
> > 3 150.100.1.254 24 msec
> >
> >
> > Testing trace to loopback of bb2:
> >
> > Rack2R6#trac 148.5.13.1
> >
> > Type escape sequence to abort.
> > Tracing the route to 148.5.13.1
> >
> > 1 148.5.226.2 0 msec 0 msec 4 msec
> > 2 148.5.235.5 16 msec 16 msec 16 msec
> > 3 148.5.135.13 24 msec * *
> >
> >
> > Just one probe does not change the result:
> >
> > Rack2R6#trace
> > Protocol [ip]:
> > Target IP address: 148.5.135.13
> > Source address:
> > Numeric display [n]:
> > Timeout in seconds [3]:
> > Probe count [3]: 1
> > Minimum Time to Live [1]:
> > Maximum Time to Live [30]:
> > Port Number [33434]:
> > Loose, Strict, Record, Timestamp, Verbose[none]:
> > Type escape sequence to abort.
> > Tracing the route to 148.5.135.13
> >
> > 1 148.5.226.2 4 msec
> > 2 148.5.235.5 96 msec
> > 3 *
> > 4 148.5.135.13 24 msec
> >
> >
> > Doing a little more tests on traceroute, I noticed
> > that repeated behavior:
> >
> > When the router is on the path (r5 on the test) it
> > answers with 3 port unreachable.
> >
> > Rack2R3#trace 148.5.2.1
> >
> >
> > 1 148.5.235.5 12 msec 12 msec 8 msec
> > <---------- three RTT reported
> > 2 148.5.235.2 24 msec * 20 msec
> >
> >
> > Rack2R5#deb ip icmp
> >
> > .Feb 28 22:20:56: ICMP: time exceeded (time to
> live)
> > sent to 148.5.235.3 (dest was 148.5.2.1)
> > .Feb 28 22:20:56: ICMP: time exceeded (time to
> live)
> > sent to 148.5.235.3 (dest was 148.5.2.1)
> > .Feb 28 22:20:56: ICMP: time exceeded (time to
> live)
> > sent to 148.5.235.3 (dest was 148.5.2.1)
> >
> > When the router is the end, is answers only 2
> port
> > unreachable:
> >
> > Rack2R3#trace 148.5.5.1
> >
> >
> > 1 148.5.235.5 12 msec * 8 msec
> > <------------- one RTT is missed
> >
> >
> > Rack2R5#
> > .Feb 28 22:22:33: ICMP: dst (148.5.5.1) port
> > unreachable sent to 148.5.235.3
> > .Feb 28 22:22:36: ICMP: dst (148.5.5.1) port
> > unreachable sent to 148.5.235.3
> >
> > Do you know the reason the router just answer two
> > packets?
> >
> >
>
This archive was generated by hypermail 2.1.4 : Sun Sep 04 2005 - 17:01:19 GMT-3