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SR 7102DL x.21 HDLC setup

Dieter Gommel
Occasional Contributor

SR 7102DL x.21 HDLC setup

i try to connect 2 SR 7102DL over a serial x.21 hdlc connection.
For testing i made a crossover kabel.
Now at startup i saw the following messages:
ser 1/1 changed state to up
ser 1/1 loss of clock
ser 1/1 changed state to down
Is the Problem the "transmit clock source"?
Olaf Borowski
Respected Contributor

Re: SR 7102DL x.21 HDLC setup

Hi Dieter,

The Quick start guide for the serial module specifies "DTE only, no internal clock provided". Result: You cannot connect 2 7000dl series routers back-2-back since one of them would have to provide the clock (for serial interface! You can do this for E1 or T1). Typically, this is provided by the network or DCE.