connecting two cisco routers

[staphisco]

Hello,   I have set up a lab of 3 physical routers.  trying to create a serial connection using crossover cable via the dsu/csu. I gave them ips and they are in the same subnet and no shut was issue but they are not up.  Please tell me what Im doing wrong.  I'm creating eigrp/ospf routing so I need to connect the 3 computers together .    BTW, im using the two g0/0 and g0/1 for internet connection so the only port left is dsu/csu.   Thx

[cj.johnson3cigna]

Is that an RJ-45 to RJ-45 Serial connection? If so, you'll need them to be a "DS1 crossover" meaning that instead of crossing over pins 1 & 2 to positions 3 & 6 you instead need 3 & 4 to go to positions 5 & 6.

To diagram:

1       |  2       |  3       |  4       |  5       |  6       |  7       |  8        Position

wo     | o        | wg     | Bl       | wBl     |  g       | wBr    | Br       Starting Pin-Outs

wo     | o        | wBl    | g        | wg      | Bl       | wBr    | Br       Ending Pin-Outs for DS1 Crossover

Compared to

wo     | o        | wg     | Bl       | wBl     |  g       | wBr    | Br       Starting Pin-Outs

wg     | g        | wo     | Bl       | wBl     | o        | wBr    | Br       Ending Pin-Outs for Ethernet Crossover

[staphisco]

Thank you but I dont understand the cabling. Please tell me what type of cable i have to buy. the back of my routers have T1 DSU/CSU port. I read that i need DTE/DCE cable but those cables dont come with an ethernet end to connect to my DSU/CSU which an ethernet port.

Please help

Thx

[Joseph W. Doherty]

Did you also configure one of the two serial ports with a clock?

[staphisco]

Thank you but I dont understand the cabling. Please tell me what type of cable i have to buy. the back of my routers have T1 DSU/CSU port. I read that i need DTE/DCE cable but those cables dont come with an ethernet end to connect to my DSU/CSU which an ethernet port.

Please help

Thx

[Julio E. Moisa]

Hi

If you are using serial cables you need to identify the DCE port and configure: clock rate 64000, also verify if the interfaces are UP UP using:

show ip interface brief

If they are administrately down you must configure: no shutdown under the interfaces. Example:

interface serial 0/0

no shutdown

Hope it is useful

:-)

[paul driver]

Hello

I assume you have enabled FR encapsulation?

Example back to back FR- no FR switch

RTR1
int serx/x
encap Fr
ip address 1.1.1.1 255.255.255.252
clock rate 64000  ( this is the dce side of the cross overcable  -  show controller x/x  | in clock  to verify)
frame-relay map ip 1.1.1.2 102
no keepaive

RTR2
int serx/x
encap Fr
ip address 1.1.1.2 255.255.255.252
frame-relay map ip 1.1.1.1 102
no keepalive

res
Paul

[staphisco]

I'm not using any frame relay. This is just straight router from time warner cable.  I did encap ppp but the ports are not coming up.  I suppose I cant do the clocking because I dont have the DTE/DTC cable.  This is my question:  Do i have to buy a specific cable to do the clocking?   The crossover cannot do it because it does not define male/female who will do the clocking.

thx

[paul driver]

Hello
I have set up a lab of 3 physical routers. trying to create a serial connection using crossover cable via the dsu/csu

I replied to this statement in your OP

For direct back to back serial connection you’ll need a dte/dce crossover cable use either FR encapsulation (example provided) or HDLC encapsulation

Res
Paul

[staphisco]

I appreciate your effort to help with this. My problem with the dte/dtc wont work because the dsu/csu port in my router. i looked at the dte end but they wont fit in with dsu port. I have attached the port of dsu/csu for you to view.


thx

[staphisco]

I appreciate your effort to help with this. My problem with the dte/dtc wont work because the dsu/csu port in my router. i looked at the dte end but they wont fit in with dsu port. I have attached the port of dsu/csu for you to view.


thx

[staphisco]

I got the ports up. I'm no using FR. Do I have to do clocking? This is just a crossover dce cable.

[Georg Pauwen]

Hello,

try the configs below:

R1
=====
interface Serial0/0
description Link to R2
ip address 192.168.1.1 255.255.255.0
service-module t1 timeslots 1-24
service-module t1 linecode b8zs
service-module t1 framing esf
service-module t1 clock source internal

R2
=====
interface Serial0/0
description Link to R1
ip address 192.168.1.2 255.255.255.0
service-module t1 timeslots 1-24
service-module t1 linecode b8zs
service-module t1 framing esf
service-module t1 clock source line

[staphisco]

thank you for helping but im not using framerelay. This is just a crossover cable. so I decided to go with

int s0/0/0

enc ppp

ip add ....

[paul driver]

Hello

---

@staphisco wrote:
thank you for helping but im not using framerelay. This is just a crossover cable. so I decided to go with

int s0/0/0

enc ppp

ip add ....

---

If your crossover cable is applicable for the controller cards you are using  ( meaning not a normal data crossover cable) specific ones for E1/T1 cards then all you need to establish connection use is HDLC encapsulation as I stated previously

review this

res
Paul