From: Tarun Pahuja (pahujat@gmail.com)
Date: Sun Nov 11 2007 - 10:36:32 ART
Muhammad,
My advice to you would be to get another Wic-1t serial
interface along with a DB60/DTE TO DB60/DCE cable. It would cost you less
than $50 for both.The more time you spend on troubleshooting layer 1 issues
in lab preparation mixing and matching cables or interfaces, the lesser time
you will get for other topics that are tested heavily. It is good to know
the underlying technology and I am glad that you ran into this issue. Now
you know, What things have to in place before even your frame-relay
interface comes up.
As Scott suggested get the right cable, you can find out which end of the
cable is DCE or DTE by just looking at the cable(usually marked) or when the
cable is connected to the interface, type in "show controller se x/x".
Anytime you are dealing with synchronous communication, one end has to
provide the clocking, It must be the DCE end in Cisco Routers when dealing
with serial interfaces. In addition to this, when you are using a
synchronous connection for frame-relay, The Router configured as a
Frame-relay switch must know that it should handle the LMI like a
frame-relay DCE device. This is achieved by executing "frame-relay intf-type
dce" command on the router acting as a Frame-relay switch. Remember the
layer one clocking goes on the DCE side, and, the frame-relay intf-type dce
command must go on the switch if you plan to use the switch for normal
operation(with LMIs). The DTE side should have encapsulation frame-relay
turned on for proper communication with the switch, the default in serial
interfaces is HDLC.
I have pasted a sample config of a typical frame-relay switch for clarity.
hostname FRAME_SWITCH
!
!
ip subnet-zero
no ip domain-lookup
*frame-relay switching*
!
!
!
interface Ethernet0
no ip address
no ip directed-broadcast
shutdown
!
interface Serial0
no ip address
interface Serial1
no ip address
no ip directed-broadcast
*encapsulation frame-relay*
logging event subif-link-status
logging event dlci-status-change
*clockrate 56000*
no frame-relay inverse-arp
frame-relay intf-type dce
* frame-relay route 122 interface Serial2 221
frame-relay route 123 interface Serial3 321*
!
interface Serial2
no ip address
no ip directed-broadcast
*encapsulation frame-relay*
logging event subif-link-status
logging event dlci-status-change
*clockrate 56000*
no frame-relay inverse-arp
frame-relay intf-type dce
*frame-relay route 221 interface Serial1 122*
HTH,
Tarun
On Nov 10, 2007 5:11 PM, dara tomar <wish2ie@gmail.com> wrote:
> *Hi Saleem,
>
> I think Mr. Brian's comment would have resolved the issue.
>
> I had face this same issue round-about 2 years back,
> The thing that comes handy herein is the command "frame-relay intf-type
> dce" and applying the clock at the correct side.
>
> And offcourse there is no need to purchase a new cable for this. :) :)
>
> Regards,
> Dara*
>
> On Nov 11, 2007 1:07 AM, Brian Dennis <bdennis@internetworkexpert.com>
> wrote:
>
> > I think you are confused as to what David said. When configuring a
> > Frame Relay switch layer 1 DCE/DTE is independent of layer 2 DCE/DTE.
> > The "clock rate" command can only be applied on the layer 1 DCE side of
> > the cable. This can be determined by looking at the cable for a DTE/DCE
> > labeling, using the "show controllers serial X/X" command or by just
> > issuing the "clock rate" command on both sides. The side that accepts
> > the command is the layer 1 DCE.
> >
> > In regards to Frame Relay layer 2 DCE is independent of the layer 1 DCE.
> > Commonly the layer 1 DCE end of the cable is connected to the FRS and
> > the layer 2 DCE is also configured on the FRS side. The configuration
> > of the Frame Relay DCE can be done by using the "frame-relay intf-type
> > dce" command. By default Frame Relay interfaces are DTE. Also as a
> > point of interest the Frame Relay DCE side is the side that commonly
> > generates LMI. I used the word commonly because although unusual you
> > can have a Frame Relay connection without LMI ;-)
> >
> > --
> >
> > Brian Dennis, CCIE4 #2210 (R&S/ISP-Dial/Security/SP)
> > bdennis@internetworkexpert.com
> >
> > Internetwork Expert, Inc.
> > http://www.InternetworkExpert.com <http://www.internetworkexpert.com/>
> > Toll Free: 877.224.8987
> > Direct: +1.775.852.3995 (Outside the US and Canada)
> >
> >
> > Muhammad Saleem wrote:
> > > Cable side does matter, I am trying to configure clock rate on the
> > interface
> > > (DB60) of 2514 and Smart Serial of 2610XM routers where I am
> connecting
> > DTE
> > > site of the cable but both interfaces go down whenever I assign clock
> > rate
> > > but if I assign clock rate to the interface of a router where I am
> > > connecting DCE side of the cable it works fine.
> > >
> > > I know this might be very simple thing but I don't know how to make an
> > > interface behaving like DCE while I am connecting DTE side of a cable
> to
> > > that interface.
> > >
> > > This is what I am trying to do
> > > I have a router connecting to two frame-relay switches, coz of the
> WIC2T
> > > with smart serial DCE end of the cable I can use these two interfaces
> > only
> > > as a DCE type but at the same time frame-relay switch has DCE
> interface
> > too.
> > > I see one option to buy a cable which has one end smart serial as DTE
> > and
> > > DB60 as DCE type.
> > > Any other way to solve this issue while using existing cables?
> > > Appreciate all responses
> > >
> > > saleem
> > >
> > > -----Original Message-----
> > > From: David Prall [mailto: dcp@dcptech.com]
> > > Sent: Saturday, November 10, 2007 12:48 AM
> > > To: 'Scott Morris'; 'Muhammad Saleem'; ccielab@groupstudy.com
> > > Subject: RE: How to use WIC2T with opposite type of connectors in
> > > Frame-relay environment?
> > >
> > > What does it matter which end is dce or dte. The dce end provides
> clock.
> > But
> > > either end can act as the frame-relay dce side. One is L1 signalling,
> > and
> > > the other is L2 signalling. They don't have to be one in the same. Use
> > the
> > > cables you have and be happy.
> > >
> > > David
> > >
> > > --
> > > http://dcp.dcptech.com
> > >
> > >
> > >> -----Original Message-----
> > >> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On
> > >> Behalf Of Scott Morris
> > >> Sent: Friday, November 09, 2007 3:53 PM
> > >> To: 'Muhammad Saleem'; ccielab@groupstudy.com
> > >> Subject: RE: How to use WIC2T with opposite type of
> > >> connectors in Frame-relay environment?
> > >>
> > >> Go to their web site and purchase the one with the DCE end on
> > >> the other
> > >> side. :)
> > >>
> > >> Scott
> > >>
> > >> -----Original Message-----
> > >> From: Muhammad Saleem [mailto:msaleems@gmail.com]
> > >> Sent: Friday, November 09, 2007 1:38 PM
> > >> To: ccielab@groupstudy.com
> > >> Cc: smorris@ipexpert.com
> > >> Subject: RE: How to use WIC2T with opposite type of connectors in
> > >> Frame-relay environment?
> > >>
> > >>
> > >> I already have Smart Serial DCE Interface to DB60 DTE
> > >> interface Crossover
> > >> Cable; point is, how I can use that cable.
> > >> I want to use the WIC2T interface of router as DTE interface
> > >> but the cable
> > >> side that can go into WIC2T is DCE.
> > >>
> > >> saleem
> > >>
> > >> -----Original Message-----
> > >> From: Scott Morris [mailto: smorris@ipexpert.com]
> > >> Sent: Friday, November 09, 2007 8:54 PM
> > >> To: 'Muhammad Saleem'; ccielab@groupstudy.com
> > >> Subject: RE: How to use WIC2T with opposite type of connectors in
> > >> Frame-relay environment?
> > >>
> > >> Companies make some SS-DB60 cables exactly for that in a lab
> > >> environment.
> > >> Otherwise, if you have the "real" cables that terminate in
> > >> v.35 connectors
> > >> they will fit together just fine!
> > >>
> > >> http://www.anthonypanda.com/product.php?prd_id=9&opt_id=29
> > >>
> > >> HTH
> > >>
> > >>
> > >>
> > >> Scott Morris, CCIE4 (R&S/ISP-Dial/Security/Service Provider)
> > >> #4713, JNCIE-M
> > >> #153, JNCIS-ER, CISSP, et al.
> > >> CCSI/JNCI-M/JNCI-ER
> > >> VP - Technical Training - IPexpert, Inc.
> > >> IPexpert Sr. Technical Instructor
> > >>
> > >> A Cisco Learning Partner - We Accept Learning Credits!
> > >>
> > >> smorris@ipexpert.com
> > >>
> > >> Telephone: +1.810.326.1444
> > >> Fax: +1.810.454.0130
> > >> http://www.ipexpert.com
> > >>
> > >>
> > >>
> > >>
> > >>
> > >> -----Original Message-----
> > >> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On
> > >> Behalf Of
> > >> Muhammad Saleem
> > >> Sent: Friday, November 09, 2007 12:33 PM
> > >> To: ccielab@groupstudy.com
> > >> Subject: How to use WIC2T with opposite type of connectors in
> > >> Frame-relay
> > >> environment?
> > >>
> > >> Dear Expert,
> > >>
> > >> I have Cisco 2610XM router with one WIC2T and one WIC1T, from
> > >> WIC2T both
> > >> interfaces are HD Smart Serial, and two cables with HD Smart Serial
> > >> connector End (DCE) that can only go to that router and other
> > >> End of these
> > >> cables have DB60 connector (DTE) that can only go to
> > >> frame-relay switches.
> > >>
> > >> How can I use these cables with frame-relay switch while cables have
> > >> opposite type of connectors?
> > >>
> > >>
> > >>
> > >> saleem
> > >>
> > >> ______________________________________________________________
> > >> _________
> > >> Subscription information may be found at:
> > >> http://www.groupstudy.com/list/CCIELab.html
> > >>
> > >> ______________________________________________________________
> > >> _________
> > >> Subscription information may be found at:
> > >> http://www.groupstudy.com/list/CCIELab.html
> > >
> > >
> _______________________________________________________________________
> > > Subscription information may be found at:
> > > http://www.groupstudy.com/list/CCIELab.html
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Sat Dec 01 2007 - 06:37:29 ART