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Strange Cisco3640 router

I have installed a Cisco3640 router with 2 modules NM-8AS. The NM-8AS modules have their interfaces configured either synchronous or asynchronous. The strange thing it happened is: while async interfaces is working fine, the sync interfaces is not working at all, although the message displayed by "sho int ser " said that interface is up. The problem is obvious with the lines runnning encapsulation PPP, because the lines running encap HDLC are working fine.

i would notice here that these interfaces were worked fine some time ago. What could be the problem ?


Re: Strange Cisco3640 router

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