From: Brian Dennis (brian@labforge.com)
Date: Sun Mar 09 2003 - 18:39:25 GMT-3
Pita,
With a multipoint interface (Frame-relay, ATM, etc) there needs to be a
mechanism to map layer 3 addresses to layer 2 addresses. This can either
be some form of ARP or manual mappings. In the original problem where
"encapsulation failed" messages were being received, that failed message
is telling you that there isn't a layer 3 to layer 2 mapping. This is
the exact same message you can receive from the "debug ip packet"
command with Frame-relay, ISDN, Ethernet, X.25, etc when a layer 3
address isn't mapped to a layer 2 address.
In the original problem, InARP should have automatically been performed
by the router once it (see below) discovers the PVC and assigns it to
the subinterface (assuming an IP address is already assigned of course).
Rack4R6#sho deb
Generic ATM:
ATM ARP events debugging is on
Rack4R6#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Rack4R6(config)#int atm0/0/0
Rack4R6(config-if)#atm ilmi-pvc-discovery subinterface
Rack4R6(config-if)#^Z
Rack4R6#
02:38:11: %SYS-5-CONFIG_I: Configured from console by console
02:38:11: ATMARP(ATM0/0/0.1): Sending first PVC INARP for 1/34
02:38:11: ATMARP(ATM0/0/0.1)O: INARP_REQ to VCD#5 1/34 for link 7(IP)
02:38:11: ATMARP(ATM0/0/0.1)I: INARP Reply VCD#5 1/34 from 54.254.1.254
Now as to way InARP didn't work in the original problem we would need
more information to determine why.
As far as the "pvc 0/5 qsaal" command is concerned it's irrelevant to
this issue. The "pvc 0/5 qsaal" command is for defining the "signaling"
PVC for SVC establishment and tear-down. It only showed up because there
is a subinterface configured off the main interface that is doing SVCs.
Brian Dennis, CCIE #2210 (R&S/ISP Dial/Security)
brian@labforge.com
http://www.labforge.com
-----Original Message-----
From: pita40 [mailto:pita40@hotmail.com]
Sent: Sunday, March 09, 2003 10:47 AM
To: Brian Dennis; 'Peter'; ccielab@groupstudy.com
Cc: stefan-uwe_vogt@web.de
Subject: Re: Re: atm ilmi-pvc-discovery
Below is an example from CCO. It is the same as Stefan except for ip
add.
Dennis your explanation as to why his config did not work is not clear.
You
said,
"Your issue is something different. The PVC (VPI/VCI) was assigned to a
multipoint subinterface which means a method to "map" layer 3 "
You had the same config as Stefan except you added qsaal signal. Below
is
CCO config. Here multipoint is also used. I am not sure what you and
Peter
are talking about with using multipoint sub. Please clarify.
Pita
Configuring PVC Discovery Example
The following example shows how to enable PVC Discovery on an ATM main
interface 2/0. The keyword subinterface is used so that all discovered
PVCs
with a VPI value of 1 will be assigned to the subinterface 2/0.1. For
further information, refer to the section "Configuring PVC Discovery"
earlier in this chapter.
interface atm 2/0
pvc RouterA 0/16 ilmi
exit
atm ilmi-pvc-discovery subinterface
exit
!
interface atm 2/0.1 multipoint
ip address 172.21.51.5 255.255.255.0
----- Original Message -----
From: "Brian Dennis" <brian@labforge.com>
To: "'Peter'" <peter@cyscoexpert.com>; <ccielab@groupstudy.com>
Sent: Sunday, March 09, 2003 11:45 AM
Subject: RE: Re: atm ilmi-pvc-discovery
> Peter,
> Look at the output of his "show atm vc" command. You can see that the
> PVC was automatically assigned to the subinterface. Why are you
> recommending that he remove the command and assign it manually if the
> PVC is already assigned to the correct subinterface? The whole purpose
> of the subinterface option is to automatically assign it to a
> subinterface so manual configuration isn't needed.
>
> Here is a working example:
>
> Rack4R6#sho run inter atm0/0/0
> Building configuration...
>
> Current configuration : 137 bytes
> !
> interface ATM0/0/0
> no ip address
> no atm ilmi-keepalive
> atm ilmi-pvc-discovery subinterface
> pvc 0/5 qsaal
> !
> pvc 0/16 ilmi
> !
> end
>
> Rack4R6#sho run inter atm0/0/0.1
> Building configuration...
>
> Current configuration : 76 bytes
> !
> interface ATM0/0/0.1 multipoint
> ip address 54.254.1.4 255.255.255.0
> end
>
> Rack4R6#sho atm pvc
> VCD / Peak Avg/Min
> Burst
> Interface Name VPI VCI Type Encaps SC Kbps Kbps
> Cells Sts
> 0/0/0 1 0 5 PVC SAAL UBR 155000
> UP
> 0/0/0 2 0 16 PVC ILMI UBR 155000
> UP
> 0/0/0.1 4 1 34 PVC-D SNAP UBR 155000
> UP
> Rack4R6#sho atm map
> Map list ATM0/0/0.1_ATM_INARP : DYNAMIC
> ip 54.254.1.254 maps to VC 4, VPI 1, VCI 34, ATM0/0/0.1
>
> Rack4R6#ping 54.254.1.254
>
> Type escape sequence to abort.
> Sending 5, 100-byte ICMP Echos to 54.254.1.254, timeout is 2 seconds:
> !!!!!
> Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
> Rack4R6#
>
> Brian Dennis, CCIE #2210 (R&S/ISP Dial/Security)
> brian@labforge.com
> http://www.labforge.com
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
Of
> Peter
> Sent: Sunday, March 09, 2003 5:52 AM
> To: ccielab@groupstudy.com
> Subject: Re: Re: atm ilmi-pvc-discovery
>
> Brian,
>
> I agree.
> But since his subinterface was multipoint you have to create a PVC
under
> it
> and either map or inarp. However you cannot create a PVC under
> subinterface
> if you don't remove discovery from major interface. If you try and
later
> type "show run" it won't be there.
> So depending on the exercise requirements you keep the discovery on
> point-to-point subinterface or just discover the PVC and statically
map
> after.
>
> _____________________________
> Peter
> #7247 (R&S, Security)
> CyscoExpert Corp.
> 4433 W. Touhy Ave. Suite 410
> Lincolnwood, IL 60712
> Phone (847) 674-3392
> Toll Free (866) CyscoXP (297-2697)
> Fax (847) 674-2625
>
>
> ----- Original Message -----
> From: "Brian Dennis" <brian@labforge.com>
> To: "'stefan vogt'" <stefan-uwe_vogt@web.de>;
<ccielab@groupstudy.com>;
> "'Peter'" <peter@cyscoexpert.com>
> Sent: Saturday, March 08, 2003 12:26 PM
> Subject: RE: Re: atm ilmi-pvc-discovery
>
>
> > Stefan,
> > You have it right. The "atm ilmi-pvc-discovery" command with the
> > "subinterface" option is used to automatically map the PVC to a
> > subinterface and isn't intended to be removed. In your case you
> > discovered the 9/120 PVC and the command automatically assigned it
to
> > the .9 subinterface (VPI = subinterface #).
> >
> > Your issue is something different. The PVC (VPI/VCI) was assigned to
a
> > multipoint subinterface which means a method to "map" layer 3 (IP
> > address) to layer 2 (ATM VPI/VCI) is needed. You could use InARP or
> > manually map the layer 3 address to the layer 2 address. If a
> > point-to-point subinterface was used no mapping would be needed as
all
> > layer 3 addresses are "mapped" to the one layer 2 address.
> >
> > As a side note when using this command in the real world I've always
> > used it with point-to-point subinterfaces.
> >
> > Brian Dennis, CCIE #2210 (R&S/ISP Dial/Security)
> > brian@labforge.com
> > http://www.labforge.com
> >
> >
> > -----Original Message-----
> > From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
> Of
> > stefan vogt
> > Sent: Saturday, March 08, 2003 7:19 AM
> > To: ccielab@groupstudy.com; Peter
> > Subject: Re: Re: atm ilmi-pvc-discovery
> >
> > Hello Peter,
> >
> > Thanks for your answer - seems I got the purpose of atm
> > ilmi-pvc-discovery completely wrong.
> > Just to confirm, you are saying that atm ilmi-pvc-discovery is just
to
> > discover the vpi/vci pair and not for permanent use in a running
> config?
> >
> > Thanks,
> > Stefan
> >
> >
> > "Peter" <peter@cyscoexpert.com> schrieb am 08.03.03 13:54:02:
> > >
> > > After discovering PVC remember the VPI/VCI pair, go ahead and
remove
> > "atm
> > > ilmi-pvc-discovery subinterface" command from the major interface,
> go
> > back
> > > to the subinterface and create the PVC you just discovered with
"pvc
> > > VPI/VCI" and type "inarp 1" under it. You should be able to ping
the
> > remote
> > > side now.
> > > After all the exercise was to discover the PVC.
> > >
> > > _____________________________
> > > Peter
> > > #7247 (R&S, Security)
> > > CyscoExpert Corp.
> > > 4433 W. Touhy Ave. Suite 410
> > > Lincolnwood, IL 60712
> > > Phone (847) 674-3392
> > > Toll Free (866) CyscoXP (297-2697)
> > > Fax (847) 674-2625
> > >
> > >
> > > ----- Original Message -----
> > > From: "stefan vogt" <stefan-uwe_vogt@web.de>
> > > To: <ccielab@groupstudy.com>
> > > Sent: Saturday, March 08, 2003 5:50 AM
> > > Subject: atm ilmi-pvc-discovery
> > >
> > >
> > > > Hello all,
> > > >
> > > > Just playing around with atm ilmi-pvc-discovery.
> > > > My config looks like this:
> > > > interface atm 2/0
> > > > pvc 0/16 ilmi
> > > > exit
> > > > atm ilmi-pvc-discovery subinterface
> > > > exit
> > > > !
> > > > interface atm 2/0.9 multipoint
> > > > ip address 172.16.10.6 255.255.255.0
> > > >
> > > > This one looks good:
> > > > r#sh atm vc
> > > > VCD / Peak
> > Avg/Min
> > > Burst
> > > > Interface Name VPI VCI Type Encaps Kbps
> Kbps
> > > Cells Sts
> > > > 2/0 4 0 16 PVC ILMI 155000
> > > UP
> > > > 2/0.9 11 9 120 PVC-D SNAP 155000
> > > UP
> > > >
> > > > But ping to remote router fails. When doing debug ip packet:
> > > > 17:05:27: IP: s=172.16.10.6 (local), d=172.16.10.7 (ATM2/0.9),
len
> > 100,
> > > sending
> > > > 17:05:27: IP: s=172.16.10.6 (local), d=172.16.10.7 (ATM2/0.9),
len
> > 100,
> > > encapsul
> > > > ation failed.
> > > >
> > > > So I assume there is some mapping for the remote ip address
> missing.
> > I
> > > searched CCO, but found no hint how to do this when using atm
> > > ilmi-pvc-discovery...
> > > >
> > > > Any input is welcome.
> > > > -Stefan
> > > >
> > > >
> > >
> >
>
This archive was generated by hypermail 2.1.4 : Sat Apr 05 2003 - 08:51:35 GMT-3