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)?
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.
Professional Services Engineer
CCIE # 21272
CBE Technologies, LLC.
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