CTS isn't needed for synchronous serial so i thought? The only time you would need clear to send is if you are asynchronous...or so i thought. My impression was that those pins were not tied to anything typically. And the wires would be tied back to DCD.
Not sure i'm correct, but logically I dont see any reason for CTS on a synchronous interface. But by all means correct me if I'm wrong. Ernest On Thu, Dec 17, 2009 at 1:04 PM, Marcelo Zilio <[email protected]>wrote: > Hi, > > Has anyone seen this in serial interfaces before? > Link is UP and traffic is going through, however router shows CTS=down > besides a lot CRCs/Input Errors. > It doesn't make sense to me the parameter which should advise that the link > is "ready to go" is DOWN while there is traffic on it. > Users are complaining some application are slow. > > The router is a Cisco 2811 IOS 12.4(15)T10. > > Router#sh int s0/1/0 > Serial0/1/0 is up, line protocol is up > Hardware is GT96K Serial > MTU 1500 bytes, BW 256 Kbit/sec, DLY 20000 usec, > reliability 255/255, txload 40/255, rxload 42/255 > Encapsulation FRAME-RELAY IETF, loopback not set > Keepalive set (10 sec) > CRC checking enabled > LMI enq sent 48, LMI stat recvd 48, LMI upd recvd 0, DTE LMI up > LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0 > LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE segmentation > inactive > FR SVC disabled, LAPF state down > Broadcast queue 0/64, broadcasts sent/dropped 7/0, interface broadcasts 0 > Last input 00:00:00, output 00:00:00, output hang never > Last clearing of "show interface" counters 00:07:55 > Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 > Queueing strategy: dual fifo > Output queue: high size/max/dropped 0/256/0 > Output queue: 0/128 (size/max) > 30 second input rate 43000 bits/sec, 68 packets/sec > 30 second output rate 41000 bits/sec, 78 packets/sec > 34746 packets input, 2956769 bytes, 0 no buffer > Received 0 broadcasts, 0 runts, 0 giants, 0 throttles > 602 input errors, 602 CRC, 433 frame, 107 overrun, 0 ignored, 323 abort > 43237 packets output, 3308125 bytes, 0 underruns > 0 output errors, 0 collisions, 0 interface resets > 0 unknown protocol drops > 0 output buffer failures, 0 output buffers swapped out > 0 carrier transitions > DCD=up DSR=up DTR=up RTS=up *CTS=down* > > Thanks, > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ > -- Ernest McCaleb _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
