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Inteface Errors

ojasvi.bansal
Level 1
Level 1

I use Shaw as my ISP and a 2611XM as router. I have been getting slow speed on the internet.

I found that when I hook my laptop directly to the modem, the speed is awesome. I called shaw and they said it has to do something with cisco routers.

Here's the output from show int command

MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,

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

Encapsulation ARPA, loopback not set

Keepalive set (2 sec)

Full-duplex, 100Mb/s, 100BaseTX/FX

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

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

Last clearing of "show interface" counters 02:54:12

Input queue: 1/75/0/0 (size/max/drops/flushes); Total output drops:

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 75000 bits/sec, 42 packets/sec

5 minute output rate 58000 bits/sec, 29 packets/sec

674210 packets input, 214814766 bytes

Received 149995 broadcasts, 0 runts, 0 giants, 0 throttles

2273 input errors, 2273 CRC, 1100 frame, 0 overrun, 0 ignored

0 watchdog

0 input packets with dribble condition detected

504432 packets output, 101138089 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out

Here's the output from sh run INt fa 0/1

mac-address ffff.ffff.ffff

ip address XX.XX.XX.XX XXX.XXX.XXX.XXX

ip nat outside

ip route-cache flow

no ip mroute-cache

speed 100

full-duplex

keepalive 2

I tried using ip mroute-cache and the errors started increasing fast. I have upto 30megs download and 2 megs upload on my internet connection.

I have tried changing the cable between the router and the modem and also speed/duplex settings on the router.

Behind the router I have a linksys 24 port POE switch.

Any suggestions on this is greatly appreciated.

1 Accepted Solution

Accepted Solutions

milan.kulik
Level 10
Level 10

Hi,

you should clarify with your ISP what speed/duplex/cable to use to connect to his device.

It looks like 100Mbps/half duplex might work in your case (you are receiving a lot of CRC errors on your input).

What kind of device is on the provider side?

Some 100Mbps hub (would explain why half duplex necessary)?

BR,

Milan

View solution in original post

8 Replies 8

paolo bevilacqua
Hall of Fame
Hall of Fame

Have you configured "ip cef" ?

How the default route is set on the router ?

Note it seems to me you should have half-duplex set on the interface going to ISP device.

mroute-cache refers to multicast that you're not using, so just leave as default ?

Yes I have configured cef.

ip route 0.0.0.0 0.0.0.0 xx.xx.xx.xx

I tried using ip route 0.0.0.0 0.0.0.0 fa 0/1

but for some reasons this doesn't work.

I will try setting it at half-duplex and will let you know the results.

What is ip virtual-reassembly

milan.kulik
Level 10
Level 10

Hi,

you should clarify with your ISP what speed/duplex/cable to use to connect to his device.

It looks like 100Mbps/half duplex might work in your case (you are receiving a lot of CRC errors on your input).

What kind of device is on the provider side?

Some 100Mbps hub (would explain why half duplex necessary)?

BR,

Milan

My ISP doesn't give me any information about this (this is what happens when monoply is in place).

It is a motorola cable modem. I cannot log in to the modem because the default username and password has been changed and my ISP would not tell me the new username and password.

I will try using a hup in between.

Thanks

OJ

YOU GUYS ARE GREAT

I changed the duplex setting from full to half and it is working perfectly.

Thank you so much.

Same problem i was facing with my ISP , it is resovled when i tried with multiple cobination like

duplex full

speed 100 or

speed 100

duplex full or kept some time auto

remeber your error should zero and duplex should full in one combinatin what we want finally.

Do you know what does this mean.

311 lost carrier, 0 no carrier

Thanks

OJ

Do clear counters, it it happens again, the "modem" may be being reset.

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