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New router showing thousands of RX CRC Errors

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Registered: 16-10-2014

New router showing thousands of RX CRC Errors

I have just replaced my TP-Link Load Balancer with a new DrayTek Vigor 2925n and after configuration the stats page is showing me lots of errors on my primary WAN interface.
I would appreciate your thoughts on this please, as it doesn't look right to me. I've never mentioned it before as I didn't know due to the lack of this information in my old TP-Link.
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Re: New router showing thousands of RX CRC Errors

What's the up-time for that interface?
If you check the CRC count after some time has it increased significantly?
Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
Opinions expressed in forum posts are those of the poster, others may have different views.
Community Veteran
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Re: New router showing thousands of RX CRC Errors

At the time it was taken it was about an hour, however when I installed the router I disconnected from Plusnet but never powered off the modems, so how historical the data is I don't know.
Since that image was taken I've had another 16 errors counted, so at that rate it looks like a lot of them are in fact historical.
Later today (read lunchtime) I'll disconnect both modems as power them off, and see what happens.
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Re: New router showing thousands of RX CRC Errors

OK, I reset the modems last night and after 14 hours of operation I now have the following.
There are errors on both lines but I don't know what constitutes too many, any thoughts?
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Re: New router showing thousands of RX CRC Errors

As I understand it (probably only very simplistically to be honest), each CRC error requires a retransmit of a chunk of data (maybe a frame?), this really only takes a small fraction of a second so around 12 CRC per hour appears pretty insignificant (average one retransmit every 5 minutes).
Look here: http://www.kitz.co.uk/adsl/DLM.htm scroll down to the table 'Standard DLM Algorithm for line categorisation', although not exactly the same thing it indicates MTBE (mean time between errors) of >250 (seconds) = 4.16minutes or 345 errors per day categorises a line as 'good' - just beware in case it creeps up beyond this level.
Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
Opinions expressed in forum posts are those of the poster, others may have different views.
Community Veteran
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Re: New router showing thousands of RX CRC Errors

Thanks for that w23, I will keep an eye on this as you suggest but from reading the link this is within the norm for the current uptime.