Input Error on WAN Circuits

[jason.poon]

Would like to know the following:

3867 input errors, 49 CRC, 0 frame, 0 overrun, 0 ignored, 474 abort

2857253 packets output, 677085019 bytes, 0 underruns

Does it means that the circuit that the telco is providing us has errors on it? Pls help

Have been receiving Lots of Input Errors and CRC Errors for the last two weeks! Pls adv.

[paddyxdoyle]

Hi,

You could check the cable between your serial interface and the NTE, and also speak to your Telco.

The errors don't look that high, are you seeing a degredation in reliability of your circuit.

sh interface serial */* will show you the reliability, it should be 255/255 for 100%

Rgds

Paddy

[jason.poon]

NTE - Sorry dont have any NTE, telco just put a rj45 socket into ur datactr. we just connect from the mutlichannel E1 Card towards the rj45 socket.

Did talked to telco, and they told us that it is not their problem. Might be our router that is giving all this errors out.

Yeah the realiability is 255/255

So what must we do on this circuit. keep complaining to telco? Pls adv what to do thx!

[dbellazetin]

These types of errors are usually a clock syncronization problem. How fast are the errors incrementing? If they are rapid I would worry, but if they are building up over a long period of time thats pretty normal.

You can clear the counters to start at 0 and check them periodically to see how fast they increment.

clear counters (interface type) (number)

If you want to verify the integrity of your interface and hardware you can create a loopback plug to test on your routers interface. Once this is done you can run an extended pings with a large amount of packets at large sizes and see if the interface gets any errors.

http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00800a754b.shtml#csudsu_hw

Telco will almost always say the line is just fine and its your own hardware.

Daniel

[jason.poon]

ya! they are increasing rapidly. Counters has been cleared and after an hour it shows almost 2xxx input errors and 19 CRC... . Does this considered rapidly?

did the ping test before putting the circuits into production. there was nothing unusual about the circuits.

now the telco, ask if they could do an intrusive test on the production circuits. but told them not on production circuits, adv them they shld hv tested the circuits before handling to customer. but they told me, the circuits were cleaned. Wanted to get a report from them and they told me they dont have any report for me!?

pls adv. what to do!

[ndarnell]

You'll have to give them some downtime to test the circuits. They should be able to do this out of business hours. It does sound like a circuit issue.

[dbellazetin]

Yes I would consider that to be excessive errors. Like mentioned above you may need to schedule a window for down time so the lines can be tested.

But first what does your configuration look like on your router? Is this an internet line or a site to site leased line?

If it is a site to site leased line then on your routers one side will be configured for clock source line and the other for clock source internal. I would swap the clock source config on each router and then see if you still get errors (only if its a private line).

Telco needs to get in on this you need to push them on it. After all you are paying for the line.

Daniel

[jason.poon]

sorry buddie, cant afford to bring the circuits down for telco. this circuits are on production for quite sometime. we'd filed complaints and open tickets and as of today, no one has came back to us on this issue

itz a site to site leased line.

yeah our clock source is line. kindly adv. which shld be clock source internal? does that make much difference?

huh... did send several mails to telco and to their immediate supervisors but seems no one care abt my issue. no reply as of today.

sorry not paying them if they dont get this fixed! that is our company rule! as adv by CIO

[dbellazetin]

I look your reply you make me laugh. Only one side needs to be set to internal and the other to line. It actually doesn't really matter which side is set to what, but depending on the local CO feeding you the line you will find that having a certain one set to line and the other to internal is better (less errors etc). Its almost like some sides feed to much power or some thing its weird.

I would just try swapping the configs. Check which is internal and which one is line and change them. Your interfaces will bounce but they should come right back up and you'll be able to see whether the errors are reduced or gone.

Daniel

[aiyappa]

Do you have any line code violations on your ciruit. if this is also increasing it could be a physical layer problem. Try grounding the cables at the router. if they are screen cables try grounding each pair connected to the router. This would probably solve the problem. This is possible as there could be an electric impedance effecting the data rate

[aiyappa]

you could also try using Baluns to reduce electric disturbances on the telco circuit by connecting the balauns back to back

[jason.poon]

hola.... thanks

did that. after clearing the interface and grounding the cables i still hv lots of input errors. and 5 crc. what other adv could u hv for me?

[burgessjt]

Time to let telco test the line, just schedule a time where it will be the least intrusive to you or your business.

[jason.poon]

did schedule a test with telco. now they proposed to do the intrusive test for 2 hrs. not sure this time frame could find any errors on the circuit. pls adv.

[dbellazetin]

Did you try switching the clocking on your routers? Believe me that can make all the difference.

Daniel