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Cisco route connected to a Cable Modem

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encarter

MIS
Jan 6, 2006
113
US
Hi i have a Cisco 1751 eth0/0 connected to a Cable Modem/Router. Both these devices are remote to me.

On the back on the cable modem there is 4 ethernet ports.

From the Cisco i get protocol down and errors (see below).

We purchased a static address from the ISP, setting this or configuring the cisco to be a dhcp client i get the same results.


What am i doing wrong...

Philly-1751#sh int eth0/0
Ethernet0/0 is up, line protocol is down
Hardware is PQUICC Ethernet, address is 0004.dd0c.e336 (bia 0004.dd0c.e336)
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)
Half-duplex, 10BaseT
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:00:04, output hang never
Last clearing of "show interface" counters 00:22:47
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
137 input errors, 0 CRC, 0 frame, 0 overrun, 137 ignored
0 input packets with dribble condition detected
137 packets output, 8220 bytes, 0 underruns
137 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
137 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out



interface Ethernet0/0
ip address dhcp
ip virtual-reassembly max-reassemblies 64
half-duplex <--- (I tried both half and full.)
crypto ipsec client ezvpn VPN
end



 
Hello
Any special reason why you are using WIC-1ENET to connect to cable modem?
Normally the port switch on the Modem will be a 100MB.Try using the 1751 fastethernet interface (leave it on auto).Also try to plug a PC in the Modem to see if ,it can get's an ip address.Post the results.
Regards
 
I will do...currently working with someone onsite to do that.


Something else i noticed when i shut the interface down and bring it back up i get :

Jul 3 15:26:26.677: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0, changed state to up
Jul 3 15:26:31.677: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0, changed state to down
Jul 3 15:26:36.677: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:27:36.677: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:28:36.678: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:29:36.678: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:30:36.678: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:31:36.678: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:32:36.679: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:33:36.679: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:34:36.679: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:35:36.679: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem?
Jul 3 15:36:36.679: %PQUICC_ETHER-1-LOSTCARR: Unit 0, lost carrier. Transceiver problem


So im thinking its the wrong kinda cable....???????

 
This is normal behavior for 10MB interface when the interface isn't administratively down.They inform you when you don't have a layer 1 connection.
Regards
 
Minue---it won't matter what interface he uses, since he'll have to use the other for a switch or whatever pc's, and coming out of the router, everything will be 10MBps.

Burt
 
Hi Burt
The switch on the cable Modem should be 100MB.I recommended the FA0/0 on the 1751,to rule out port negotiation issue's.Maybe the cable modem doesn't want to run at 10MB.
Regards
 
Oh, I see what you're saying. Sometimes the modems (like my dsl) are 10MB/half, though. But I see what you're saying now. My bad...

Burt
 
Yes that's true as well!My's run at 10MB and half duplex.
But still some provider's offer 100MB,so that users can still have a good rate for file sharing between their LAN's.
Regards
 
if the speed or duplex is wrong. Would i still see the same result above? line protocol down.
 
Yes!If I remembered correctly "Ethernet0/0 is up" means the physical connection is OK!The "line protocol is down/up mean's the Layer 2 status.The problem is the cable or duplex!
Regards
 
i just turn on a spare 1751 i have here with no cables plugged in and they both so Status=UP...so im thinking that is not the physical layer and more like its not administratively down.

 
Hello
With ethernet interface you will alway get Status=UP on the physical,even though you have need cable attached.This different with the Serial interfaces.Please have some faith in us.Try go through the trouble-shooting steps I mentiuon above.
Regards

 
Plus Minue - I am getting the same results as the production router that we are troubleshooting.

So i think that its a cable issue


From Cisco:

%PQUICC-1-LOSTCARR : Unit [dec], lost carrier. Transceiver problem?

Explanation The Ethernet 10BASE-T cable is unplugged.

Recommended Action Reconnect the 10BASE-T Ethernet cable.
 
sorry i was posting and i took ages before seeing you had posted. Will do... i have faith lol...

thanks

 
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