Please Somebody Help me

[harris-ross]

I have recently purchased a cisco 831 for my LAN. I have cable modem. I have connected cisco 831 using both straight-through and cross-over cables to my cable modem but it does not work? No communication whatsoever?

Please tell does the 831 work with all cable modems or not? I thought cable modem was all the same technology or does it vary from different suppliers?

I have tried 2 different 831 routers because I thought the first was dodgy, but even with second one I still get no communication at all.I know my cable modem is working because if plug my pix firewall it picks up signal no problem.

Please find below the output of the "show interface Ethernet1" Ethernet1 is my WAN port on the 831 router.

Ethernet1 is up, line protocol is down

Hardware is PQUICC_FEC, address is 0011.93b4.a97c (bia 0011.93b4.a97c)

Internet address will be negotiated using DHCP

MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,

reliability 128/255, txload 1/255, rxload 1/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Auto-duplex, Unknown Speed

ARP type: ARPA, SNAP, ARP Timeout 04:00:00

Last input never, output 00:00:04, output hang never

Last clearing of "show interface" counters never

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

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, 0 no buffer

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 input packets with dribble condition detected

129 packets output, 73026 bytes, 0 underruns

129 output errors, 0 collisions, 0 interface resets

0 babbles, 0 late collision, 0 deferred

136 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out

[dbellaze · Accepted solution]

Try plugging your 831 into the modem again, but this time hard set the speed and duplex on the ethernet1 interface.

duplex full

speed 100

If you can hard set on your modem that would be good too. You should be able to use the 831 w/a cross over.

Daniel

[murphyj]

set the port speed to 10 and duplex half and try both cables again. also if you have a hub handy you can use it for troubleshooting, plug both devices in, the goal would be to try and get link lights.

also note your E0 and E1 are not 100Mb devices so please try 10 half

p.s. dont forget to reboot the cable modem after you move it over. Road runner and others seem to require this anytime there is a mac/host change.