🚀 go-pugleaf

I am preparing to move our router from its present location to
another facility located several miles away.  The two locations are
networked together with an ethernet bridge over a serial line.
To minimize down time, I intend to install a spare router in the new
facility, and use a separate leased line to our routing neighbor.  
Before bringing down the old connection, I want to be certain the new 
one will work.

Here is the problem.  Although the CSU/DSU passes its remote loopback test
with the other end, I cannot ping my own serial interface and get a response.
To eliminate problems with the CSU/DSU setup (internal vs. external timing,
etc.), I want to loop the CGS serial interface back upon itself and try to
get a valid ping response.  What are the proper signal connections,  are there
any special config commands necessary, and does the ethernet port need to
be connected?

Serial port 0 has a male connector, so it is DTE according to the hardware
manual.  Apparently the operating router gets it's clock from the CSU/DSU, as
it has no clockrate commands in the config.  The spare router's TXC light does
not come unless the config line <clockrate 56000> is entered.

I have made an attempt I thought should work.  The following pin groups
were connected.

	pins 2,3	(TX,RX)
	pins 4,5	(RTS,CTS)
	pins 15,17	(TXC,RXC)
	pins 6,8,20	(CD, ,DTR)

According to the cisco manual, pin 8 is unused, however leaving pin 8
unconnected extinguishes the red Rx line signal detect LED.
                                  
If anyone can tell me how to do this, I will be grateful, and ready to
tackle the next piece of hardware in the chain.

Thanks for any and all advice.

Tom Benjamin
Computer/Network Support
Lockheed Austin Division
(512)-386-2887
thomasb@austin.lockheed.com     (don't use the <From:> address)