Re: Inverse-ARP with no LMI

"because what is it, inverse-arp is used to stop sending requests, but the
router will always respond to requests it receives right?"

I had a physical
link on one router and multipoint subinterface on another
router. No fram
interface-dlci or fram map commands were configured. Although
I could see
inArp requests sent by the router with the physical link
configuration, the
router with the multipoint subinterface would not respond
unless I put
the fram interface-d command in its configuration.

So from that experiment
I would say that it depends on the config if a router
will respond to inArp
requests.

Dave :)

 Make a small loan, Make a big difference - Kiva.org
________________________________
From: garry baker <baker.garry_at_gmail.com>
To:
Muzammil Malick <malickmuz_at_gmail.com>
Cc: mikhail.detochkin_at_gmail.com; Cisco
certification <ccielab_at_groupstudy.com>
Sent: Sun, October 17, 2010 11:58:23 AM
Subject: Re: Inverse-ARP with no LMI

i think that makes sense, in the fact
that lmi is used to learn about the
dlci and then once you have the dlci
either via lmi or static mapping then
inverse-arp can do its job

like you are
saying if you start to mix and match all over the place you are
going to see
'strange' behaviors from the router not having all the
information it needs to
get started

because what is it, inverse-arp is used to stop sending requests,
but the
router will always respond to requests it receives right?

always a
confusing topic for me, cause when we do it in the real world it is
always
just p2p and the telco just makes it work, in my limited experience
where i
still use frame-relay

--
Garry L. Baker
"There is no 'patch' for stupidity."
- www.sqlsecurity.com
On Sun, Oct 17, 2010 at 10:52 AM, Muzammil Malick
<malickmuz_at_gmail.com>wrote:
> Ok so Cisco says that inverse arp requires LMI
to be on so it knows
> what DLCIs to map.
> However coming back to my
question. Inverse-ARP still functions if LMI
> is off, just as long as the
"frame-relay interface-dlci" command is
> configured.
> What I was doing wrong
was that I had not disabled LMI on the FR
> Switch so the interfaces were
down.
> When I disabled LMI on Switch the interfaces came up and Inverse-ARP
works
> fine:
>
> interface Serial1/0
>  ip address 10.0.0.1 255.255.255.0
> 
encapsulation frame-relay IETF
>  no keepalive
>  serial restart-delay 0
> 
frame-relay interface-dlci 102
>
> *Oct 17 16:46:55.615: Serial1/0(o): dlci
102(0x1861), pkt encaps
> 0x0300 0x8000 0x0000 0x806 (ARP), datagramsize 30
>
*Oct 17 16:46:55.619: FR: Sending INARP Request on interface Serial1/0
> dlci
102 for link 7(IP)
> *Oct 17 16:46:55.659: broadcast dequeue
> *Oct 17
16:46:55.659: Serial1/0(o):Pkt sent on dlci 102(0x1861), pkt
> encaps 0x300 
0x8000 0x0    0x806 (ARP), datagramsize 30
> *Oct 17 16:46:55.751:
Serial1/0(i): dlci 102(0x1861), pkt encaps
> 0x0300 0x8000 0x0000 0x806 (ARP),
datagramsize 30
> *Oct 17 16:46:55.751: Serial1/0: frame relay INARP received
>
> R0#sh frame-relay map
> Serial1/0 (up): ip 10.0.0.2 dlci 102(0x66,0x1860),
dynamic,
>              broadcast,
>              IETF
>
> I know this is not
normal behaviour but I just wanted to know if
> inverse-arp is dependent on
LMI and this shows that it isnt.
>
> Thanks
>
> On 17 October 2010 15:16, 
<mikhail.detochkin_at_gmail.com> wrote:
> >
>http://www.cisco.com/en/US/tech/tk713/tk237/technologies_q_and_a_item09186a0
08009457a.shtml
>l
> >
> > Q. Can Frame Relay Inverse Address Resolution
Protocol (IARP) work
> without
> > Local Management Interface (LMI)?
> >
> >
>
> A. No. It uses LMI to determine which permanent virtual circuits (PVCs)
> to
> > map.
> >
> >
> > On Oct 17, 2010 5:58pm, Muzammil Malick
<malickmuz_at_gmail.com> wrote:
> >> Hi all
> >>
> >>
> >>
> >> When I have the
following config I have no problems with connectivity
> >>
> >> and I can see
inverse-arp requests and replies:
> >>
> >>
> >>
> >>
> >>
> >> interface
Serial1/0
> >>
> >>  ip address 10.0.0.1 255.255.255.0
> >>
> >> 
encapsulation frame-relay IETF
> >>
> >>  serial restart-delay 0
> >>
> >> 
frame-relay interface-dlci 102
> >>
> >> end
> >>
> >>
> >>
> >> However when
I switch off LMI on the interface (below) I can only see
> >>
> >> inverse-arp
requests but no replies and so ping fails. Is inverse-arp
> >>
> >> dependent
on LMI?
> >>
> >>
> >>
> >> interface Serial1/0
> >>
> >>  ip address 10.0.0.1
255.255.255.0
> >>
> >>  encapsulation frame-relay IETF
> >>
> >> no keepalive
> >>
> >>  serial restart-delay 0
> >>
> >>  frame-relay interface-dlci 102
>
>>
> >> end
> >>
> >>
> >>
> >> Thanks
> >>
> >>
> >>
> >>
> >>
> >> Blogs and
organic groups at http://www.ccie.net
> >>
> >>
> >>
> >>