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CSU DSU cards back to back

stevec90
Level 1
Level 1

How do I configure 2 CSU/DSU cards back to back? I have set the clock rate on DCE end and set both cards to use the line clock (as opposed to internal clock)?

1 Accepted Solution

Accepted Solutions

Hello Steve,

If they're back-to-back then you'll need a crossover cable. The cable that Cisco ships assumes that you're connecting the card to a DMARC which in this case you are not so you'll need a crossover. Pin 1 to Pin 4, Pin 2 to Pin 5 will make the cable a crossover.

Hope this helps.

David Lucas

Professional Services Engineer

CCIE # 21272

CBE Technologies, LLC.

M 857-212-9225

T 617-514-1713

F 617-514-1813

David.Lucas@cbetech.com

CONFIDENTIALITY NOTICE: The contents of this email, all related responses and any files and/or attachments transmitted with it are CONFIDENTIAL and are intended solely for the use of the individual or entity to whom they are addressed (or authorized to receive for the addressee). This email may contain legally privileged information and may not be disclosed or forwarded to anyone else without authorization from the originator of this email. If you have received this email in error, please notify the sender immediately and delete all copies from your system.

View solution in original post

6 Replies 6

david.lucas
Level 1
Level 1

Hello Steve,

You'll also need a crossover cable.  If the CSU/DSU card is set for T1 then you'll need a T1 crossover (1 to 4, 2 to 5).  If the CSU/DSU is using something similar to a 56k then you should be able to use a Cisco Console cable with RJ45 on both sides.  As for clocking, one card should be set to internal (probably the DCE side) and the other card set to line.

Hope this helps.

Dave

When it comes to CSU DSU, I don't have any experience. The cable I am using is: 1 x Cisco 6 ft DSU/CSU Blue RJ45 Router Cable, CAB-DSU-RJ45

Sh controllers gives me this:


Interface Serial0/0
Hardware is PowerQUICC MPC860 with Integrated FT1 CSU/DSU module
TX and RX clocks detected.
idb at 0x82706E0C, driver data structure at 0x8270E530

On my other router I have this: (the same)

nterface Serial0/0
Hardware is PowerQUICC MPC860 with Integrated FT1 CSU/DSU module
TX and RX clocks detected.

Also, the sh service-module:

RB#sh service-module
Module type is T1/fractional
    Hardware revision is 0.152, Software revision is 20050811-0.3,
    Image checksum is 0x80ACD1B3, Protocol revision is 0.1
Transmitter is sending remote alarm.
Receiver has loss of signal, loss of frame,
Framing is ESF, Line Code is B8ZS, Current clock source is line,
Fraction has 24 timeslots (64 Kbits/sec each), Net bandwidth is 1536 Kbits/sec.
Last module self-test (done at startup): Passed
Last clearing of alarm counters 01:44:40
    loss of signal        :    1, current duration 01:44:31
    loss of frame         :    1, current duration 01:44:31
    AIS alarm             :    0,
    Remote alarm          :    0,
    Module access errors  :    0,
Total Data (last 6 15 minute intervals):
    273512 Line Code Violations, 0 Path Code Violations
    1060 Slip Secs, 5400 Fr Loss Secs, 5380 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 5400 Unavail Secs
Data in current interval (870 seconds elapsed):
    48422 Line Code Violations, 0 Path Code Violations
    139 Slip Secs, 870 Fr Loss Secs, 870 Line Err Secs, 0 Degraded Mins
    0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 870 Unavail Secs

Hello Steve,

as Dave has suggested you need to build a special crossover cable for this

http://www.t-radtalk.com/howto/how_to_make_a_t1_cross_over.htm

Hope to help

Giuseppe

The cable that I ordered with this device is specifically designed for CSU/DSU cards, so if it's not the correct cable, then is this cable designed to connect with a different device, like a DTE device?

Hello Steve,

If they're back-to-back then you'll need a crossover cable. The cable that Cisco ships assumes that you're connecting the card to a DMARC which in this case you are not so you'll need a crossover. Pin 1 to Pin 4, Pin 2 to Pin 5 will make the cable a crossover.

Hope this helps.

David Lucas

Professional Services Engineer

CCIE # 21272

CBE Technologies, LLC.

M 857-212-9225

T 617-514-1713

F 617-514-1813

David.Lucas@cbetech.com

CONFIDENTIALITY NOTICE: The contents of this email, all related responses and any files and/or attachments transmitted with it are CONFIDENTIAL and are intended solely for the use of the individual or entity to whom they are addressed (or authorized to receive for the addressee). This email may contain legally privileged information and may not be disclosed or forwarded to anyone else without authorization from the originator of this email. If you have received this email in error, please notify the sender immediately and delete all copies from your system.

Thanks for the clarification. I understand now that you have added the DMARC specification/function with the cable, thank you.

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