MPLS Errors Help?

Unanswered Question

I am using 5mbps MPLS over Ethernet connection. Its working fine but I saw many error messages in input and output. Can anyone help me. Sh int fa 0/1 below

yourname#sh int fastEthernet 0/1

FastEthernet0/1 is up, line protocol is up

Hardware is MV96340 Ethernet, address is 001d.a16c.9041 (bia 001d.a16c.9041)

Internet address is

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

reliability 253/255, txload 5/255, rxload 4/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Half-duplex, 10Mb/s, 100BaseTX/FX

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

Last input 00:00:06, output 00:00:00, 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 171000 bits/sec, 30 packets/sec

5 minute output rate 200000 bits/sec, 36 packets/sec

1610089 packets input, 1192832548 bytes

Received 17850 broadcasts, 24 runts, 0 giants, 0 throttles

90 input errors, 66 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog

0 input packets with dribble condition detected

1556576 packets output, 841916394 bytes, 0 underruns

31749 output errors, 0 collisions, 1 interface resets

0 babbles, 31749 late collision, 0 deferred

0 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out


---sh run

interface FastEthernet0/1

ip address

duplex auto

speed 10.

Need help and advice.

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guruprasadr Tue, 11/27/2007 - 04:09

HI Imran, [Pls Rate if HELPS]

May be this Interface connected to the Service Provider.

Refer the MTU Definition if any require for the Interface or if ISP has defined some MTU Size on their interface.

Do Check with your ISP For:

1. Speed

2. Duplex

3. MTU Values

4. Bandwidth parameter if any required.

Pls Rate if HELPS

Best Regards,

Guru Prasad R

mheusing Tue, 11/27/2007 - 04:58


on output you have late collisions and your interface is set to 10 Mb/s half-duplex. Check the following:

1) does the duplex setting match the provider interface settings?

2) Do your interface settings on both ends of your EoMPLS circuit match?

If the provider has full duplex on both of his interfaces to you, which is not unlikely the case, then your end devices have to match. But even in case both are set to half duplex, the round trip time will be too large to avoid collisions, as the "cable length", i.e. circuit length, is much longer than the 100 meters specified for ethernet. That would explain the late collisions.

[Edit] Note that auto negotiation does default to 10 Mb/s half duplex and there are known cases where autonegotiation does not work.

My recommendation is to set all involved interfaces to full duplex assuming your provider supports that.

Hope this helps! Please rate all posts.

Regards, Martin


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