From: Brian Hescock (bhescock@xxxxxxxxx)
Date: Wed Nov 28 2001 - 10:30:20 GMT-3
The requirement was to use an access-list.
Wayne Lewis wrote:
> Easier - do an extended ping and choose the record route option.
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
> Brian Hescock
> Sent: Tuesday, November 27, 2001 4:42 PM
> To: PimpDaddy
> Cc: ccielab@groupstudy.com
> Subject: Re: lab 16 asymetrical routing verification
>
> You can use an access-list for testing instead of debugs or a sniffer in a
> lot
> of situations (i.e. not many people have wan sniffers)
>
> access-list 100 permit ip host a.b.c.d host e.f.g.h
> access-list 100 permit ip any any
>
> access-list 101 permit ip host a.b.c.d host e.f.g.h
> access-list 101 permit ip any any
>
> where a.b.c.d is the ping destination and e.f.g.h is the ping source (this
> is
> the echo reply so they're in the reverse order)
>
> apply one access-list to each of the outbound interfaces (back toward the
> ping
> source). Ping from the pc and once the ping test stops, do "show
> access-list" and look at the number of matches in the first line of both
> access-lists, that's the number of packets that used that path. However,
> you
> would need to ping something behind this router because if you ping the
> router
> itself, outbound access-lists aren't applied to packets generated by the
> router itself (the echo replies). Or just put the access-list on an
> inbound
> interface on the next-hop router.
>
> But if all you're checking is which path is being used (not testing
> load-sharing) and no requirement to use access-lists, Pimp's solution is
> much
> quicker and easier.
>
> Brian
>
> PimpDaddy wrote:
>
> > filter out icmp echo reply on the router on which the ping packet left.
> if
> > you get an echo reply on your machine, you know it came on the alternative
> > path, hence asymmetrical routing.
> >
> > HTH,
> > Steve
> >
> > > This may be a dumb question but how do you verify asymetrical routing
> > > using an access-list ? Lab 16 requests to have pings travel over the
> > > frame network to reach r4 and the reurn path should be across a
> > > point-point connection. How can I check this operation ? The hints
> > > indicate that you can verify by using an access-list...
> > >
> > > Anyone who has done this before, your input would be greatly
> > > appreciated !
> > >
> > > Thanks
> > > unsubscribe from the CCIELAB list, send a message to
> > > majordomo@groupstudy.com with the body containing:
> > > unsubscribe ccielab
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