sam sneed wrote: > > this is about the comment > > " You'd get a link but lots of collisions, eh? The half-duplex > side would > receive while it was sending, because the full-duplex side > would send > whenever it wanted. In other words, the 2500 side would report > collisions, > assuming there was enough simultanesous traffic." > > I hooked up a 2501 eth0 to a 3548 set to full duplex and speed > 100. > Interestingly the link light on the router lights up but no the > switch.
That's probably because of the speed mismatch not the duplex mismatch? In some cases you can get a link light and think everything is fine, when actually there are problems due to a duplex mismtach. I don't have the equipment to show you an example, but I know I've seen it. Needless to say, it makes troubleshooting difficult. Priscilla > The > switch sees the total link down and would not even bother > sending. I plugged > it into an auto-neg port and it obviously worked. Here is the > output from > switch. > > Cisco3500-3#sh int fa0/17 > FastEthernet0/17 is down, line protocol is down > Hardware is Fast Ethernet, address is 0002.fd45.4b91 (bia > 0002.fd45.4b91) > MTU 1500 bytes, BW 0 Kbit, DLY 100 usec, > reliability 255/255, txload 1/255, rxload 1/255 > Encapsulation ARPA, loopback not set > Keepalive not set > Full-duplex, 100Mb/s, 100BaseTX/FX > ARP type: ARPA, ARP Timeout 04:00:00 > Last input never, output never, output hang never > Last clearing of "show interface" counters 1y40w > Queueing strategy: fifo > Output queue 0/40, 0 drops; input queue 0/75, 0 drops > 5 minute input rate 0 bits/sec, 0 packets/sec > 5 minute output rate 0 bits/sec, 0 packets/sec > 0 packets input, 0 bytes > Received 0 broadcasts, 0 runts, 0 giants, 0 throttles > 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored > 0 watchdog, 0 multicast > 0 input packets with dribble condition detected > 0 packets output, 0 bytes, 0 underruns > 0 output errors, 0 collisions, 2 interface resets > 0 babbles, 0 late collision, 0 deferred > 0 lost carrier, 0 no carrier > 0 output buffer failures, 0 output buffers swapped out > Cisco3500-3# > > > > > > ""Priscilla Oppenheimer"" wrote in > message > news:200211141830.SAA03800@;groupstudy.com... > > The Long and Winding Road wrote: > > > > > > ""John Tafasi"" wrote in message > > > news:200211141056.KAA04663@;groupstudy.com... > > > > Hi, > > > > > > > > I have a cisco 2516 router with an ethernet interface. How > > > can I find out > > > if > > > > this inteface is full duplex or half duplex? > > > > > > plug it into a full duplex 100 mbs switch port and see if > link > > > occurs? > > > > You'd get a link but lots of collisions, eh? The half-duplex > side would > > receive while it was sending, because the full-duplex side > would send > > whenever it wanted. In other words, the 2500 side would > report collisions, > > assuming there was enough simultanesous traffic. > > > > I think the best answer is that the 2500 routers pre-date the > full-duplex > > standard. I bet they don't do full-duplex. > > > > > > > > seriously, I believe all routers in the 25xx line are > 10/half. > > > > > > there is no report on speed and duplex on routers that I can > > > find. > > > > That's annoying. I guess show run would show you a > non-default setting, > but > > that's not too helpful. > > > > Priscilla > > > > > show int > > > on a switch gives you a status > > > > > > Encapsulation ARPA, loopback not set > > > Keepalive set (10 sec) > > > Auto-duplex, Auto-speed > > > > > > even on a router with a port that do duplex changes ( 3640 > > > NM-4E )there is > > > no status. > > > > > > I don't have access to a router with a port that permits > speed > > > and duplex > > > changes.so I can't compare. > > > > > > > > > > > > > > > > > > > > > Thanks > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=57472&t=57431 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]