From: Lee Donald (Lee.Donald@t-systems.co.uk)
Date: Thu Sep 08 2005 - 12:08:44 GMT-3
Duongla,
You are correct, my apologies.
I thought it was the other way around. Maybe I'm thinking of OSPF and EIGRP
that add their own costs on.
Maybe it is a bug then?
-----Original Message-----
From: Duongla [mailto:duongla@vnn.vn]
Sent: 08 September 2005 15:53
To: Lee Donald; Cisco certification
Subject: Re: IPv6 RIP metric: strange calculation
Lee,
If you debug ip rip on your R1, you will see that R1 receives the route
222.22.2.0/24 with metric of 7 an R1 installs this route into its routing
table with metric of 7. Then R1 sends out the route to R2 with metric of 8
which has been added by 1.
Double-check you'll see.
Regards
Duongla
----- Original Message -----
From: "Lee Donald" <Lee.Donald@t-systems.co.uk>
To: "Duongla" <duongla@vnn.vn>; "Lee Donald" <Lee.Donald@t-systems.co.uk>;
"Cisco certification" <ccielab@groupstudy.com>
Sent: Thursday, September 08, 2005 9:50 PM
Subject: RE: IPv6 RIP metric: strange calculation
> Duongla,
>
> That is not correct. The router will add it's own cost on before
installing
> in the routing table. It will then advertise the route to R3 with the same
> cost as it has.
>
> To prove it here is my setup.
>
>
>
> R1 has a rip route 222.22.2.0/24 as shown.........
>
> R 222.22.2.0/24 [120/7] via 192.10.1.254, 00:00:15, FastEthernet0/0
>
> R2 learns this route from R1 and this is the route in R2's table......
>
> R 222.22.2.0/24 [120/8] via 12.12.13.1, 00:00:18, Serial0/0
>
> R2 has added an additional hop ( it's own cost) and installed it in it's
> routing table.
>
>
> My Topology is as follows............ R1---ser0/0-----ser0/0----R2
>
> I HTH
>
> Lee.
>
>
>
>
>
> -----Original Message-----
> From: Duongla [mailto:duongla@vnn.vn]
> Sent: 08 September 2005 15:35
> To: Lee Donald; Cisco certification
> Subject: Re: IPv6 RIP metric: strange calculation
>
> Lee,
> As far as I know, the normal behaviour of RIP (both ipv4 and ipv6) is:
when
> a router receives a route with metric of N then it installs the route in
the
> routing table with metric of N ( no increase). Then the router will
> advertise the route out its interfaces with metric of (N+1).
> Do you agree ?
> Here, the problem is at R2: it increases the metric by one before it
> installs the route int routing table. That's why R2 sees Z 2 hops away. In
> fact, it is just 1 hop. And from R3 and on if we have a chain of routers,
> the metric of route to Z will be 1 hop count greater than its actual
metric.
>
> Thanks
> Duongla
> ----- Original Message -----
> From: "Lee Donald" <Lee.Donald@t-systems.co.uk>
> To: "Duongla" <duongla@vnn.vn>; "Lee Donald" <Lee.Donald@t-systems.co.uk>;
> "Cisco certification" <ccielab@groupstudy.com>
> Sent: Thursday, September 08, 2005 9:33 PM
> Subject: RE: IPv6 RIP metric: strange calculation
>
>
> > Duongla,
> >
> > You've said below that R2 receives the route with a metric of 1, then R2
> > would add it's own cost onto the route, so R2 now has a cost of 2 for
this
> > route. R2 would send this route to R3 with a cost of 2, R3 would add
it's
> > own cost on and then R3 would have this route with a cost of 3.
> >
> > That is correct as far as I can read it??
> >
> > Regards
> >
> > Lee.
> >
> >
> > :)
> >
> >
> >
> >
> >
> > -----Original Message-----
> > From: Duongla [mailto:duongla@vnn.vn]
> > Sent: 08 September 2005 15:22
> > To: Lee Donald; Cisco certification
> > Subject: Re: IPv6 RIP metric: strange calculation
> >
> > Hi Lee
> >
> > From R3, the metric to destination Z should be 2 hop-counts (R2-R1). The
> > problem starts at R2, he he.
> > Pls review the scenario if you could help.
> >
> > Thanks
> > Duongla
> > ----- Original Message -----
> > From: "Lee Donald" <Lee.Donald@t-systems.co.uk>
> > To: "Duongla" <duongla@vnn.vn>; "Cisco certification"
> > <ccielab@groupstudy.com>
> > Sent: Thursday, September 08, 2005 9:15 PM
> > Subject: RE: IPv6 RIP metric: strange calculation
> >
> >
> > > What problem?
> > >
> > > R3 should have a metric of 3 should it not?
> > >
> > > On your topology R2 has the route with a metric of 2, passes it to R3,
> now
> > > R3 has the route with a metric of 3, hop count has increased by 1 hop,
> > which
> > > is correct.
> > >
> > > Regards
> > >
> > > Lee.
> > >
> > >
> > >
> > > -----Original Message-----
> > > From: Duongla [mailto:duongla@vnn.vn]
> > > Sent: 08 September 2005 14:54
> > > To: Cisco certification
> > > Subject: IPv6 RIP metric: strange calculation
> > >
> > > Hi group,
> > >
> > > Doing a simple IPv6 RIP lab on 3 routers:
> > > f0/0-R1-s0/0------s0/0-R2-s0/1------s0/0-R3-f0/0
> > > Suppose R1 f0/0 IPv6 address is Z.
> > > I noticed the following:
> > > R1 advertises Z with metric of 1: this is normal behaviour
> > > R2 receives the route Z with metric of 1. "show ipv6 route" output
> shows
> > > route Z with metric 2. R2 continues to send route Z metric 2 to R3
> without
> > > increasing the metric.
> > > R3 has a route to Z with metric 3. It also sends the route out int
> f0/0
> > > with
> > > metric 3.
> > > All my routers use c2600-is-mz.122-15.T16.bin. Is this the bug of the
> IOS
> > ?
> > >
> > > Has anyone got the same problem ?
> > >
> > > Regards
> > > Duongla
> > >
> > >
This archive was generated by hypermail 2.1.4 : Sun Oct 02 2005 - 14:40:14 GMT-3