Qos problems

Unanswered Question
Dec 6th, 2007
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We connected an Aastra voip central to our network. When the Aastra central is configured to use Qos 5 in vlan 1790 (our voice vlan), we receive a lot of input errors and runts, so no communication is possible anymore. When the central is not configured to use qos everything is normal. I use the default auto qos voip trust settings, i tested it also without qos settings and still the same behaviour. We connected the central to 3750 catalyst switches.

Does anyone know why we receive runts?



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mchin345 Thu, 12/13/2007 - 14:53
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Ensure that both devices are configured properly. Both sides should be set to auto speed and auto duplex, or hard set to the same speed and duplex settings. Runts are Ethernet packets that are less than 64 bytes and may be caused by excessive collisions. So verify the speed and mode.


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