DTE / DCE cable?

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Hi All,
I just took delivery of a 3640 router with 4 port serial card, and 2 cables
to connect to the serial ports of my 2 Cisco 1600r routers. The cables have
DTE and DCE on either end, does it matter which end goes into the different
routers? Planning to set them up as end points with the 3640 as a frame
relay router.

TIA

JV


Re: DTE / DCE cable?

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    It doesn't and it does.

    By doesn't, you can put the DCE to one router and the DTE to
another router.  As long as you are connecting it to a serial port,
you're good to go.  

    But you have to set the clock on the serial interface of the
router that the DCE end is connected to.  Not necessary on the DTE
end.  

    Regards,



                        Fred

Re: DTE / DCE cable?
Yes it does matter.  The DCE goes to your 3640(hub) the DTE goest to your
other routers(spokes).  You'll have to enable frame-relay switchging on the
3640.  I would suggest going to cisco.com and do a search on frame-relay
switching.  You be able to get to an example of wthe config you'll need.
Also don't forget if your using OSPF on your spokes you may need to do some
exztra configuration to get hellos going between the spokes.  The same goes
for RIP and split horizon and inverse ARP.
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Re: DTE / DCE cable?
http://www.cisco.com/warp/public/125/fr_switching.pdf  here ya go
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Re: DTE / DCE cable?
Thanks for the info chaps, I worked through the example in the document, and
have got it working now.

Nice one.
JV
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Re: DTE / DCE cable?
Or should I say, it works to the point where from one PC the other works ok
in one direction but not the other. I added static routes to both PC's and
killed the windows firewall at both ends but it still fails. If I ping from
the router connected to the end that fails to reply, it also fails. Not sure
why, will take a closer look tomorrow.

JV
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Re: DTE / DCE cable?
I would suggest adding the static routes in the routers; it would also be
better to use dynamic routing protocols.  The reason is that the computer
may know where to send traffic which is destined for a remote network, but
if the next hop router receiving the traffic does not know where the
destination network is as well, it will drop the packet.

I would suggest the following:

   Network #1 (suggest 172.16.1.X / 255.255.255.0)
   Network #2 (suggest 172.16.1.X / 255.255.255.0)
   Frame-Relay Network - whatever IP addresses you decide to use; my example
uses 10.1.1.1 on 1600 #1 and 10.1.1.2 on 1600 #2

      PC #1
         configure with an IP address (172.16.1.1), subnet mask
(255.255.255.0), and a default gateway (172.16.1.254)
      1600 #1
         configure the eth0 with an IP address (172.16.1.254) and subnet
mask (255.255.255.0)
         configure the frame relay elements however you are setting them up
         configure a static route to the remote network (ip route 172.16.2.0
255.255.255.0 10.1.1.2)

      PC #2
         configure with an IP address (172.16.2.1), subnet mask
(255.255.255.0), and a default gateway (172.16.2.254)
      1600 #2
         configure the eth0 with an IP address (172.16.2.254) and subnet
mask (255.255.255.0)
         configure the frame relay elements however you are setting them up
         configure a static route to the remote network (ip route 172.16.1.0
255.255.255.0 10.1.1.1)

I cannot go very specific on the frame-relay as you may be configuring the
frame-relay any number of ways.

For testing, try to also PING the default gateway for the remote network.
As an example, PC #1 can also attempt to PING 172.16.2.254, not just the
host at 172.16.2.1.  With frame-relay being the more complicated portion of
this exercise, I would concentrate more on the frame-relay configuration and
troubleshooting.

Reference this CiscoPress article which includes frame-relay switch
configuration and frame-relay verification:
http://www.ciscopress.com/articles/article.asp?p=170741

     ===========
     Scott Perry
     ===========
Indianapolis, Indiana
________________________________________

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