# Cisco Duplex Mismatch



## beefcake2999 (Aug 18, 2003)

I have a Cisco 831 router and a cisco 2700 Switch.
When i connect the switch to the router i receive duplex mismatch errors on the switch

```
CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on fastEthernet0/8 (not Half duplex),  (routername) Ethernet1 (half Duplex)
```
The strange part is that fastEthernet0/8 on the switch is hard coded to full duplex and Ethernet1 on the router is hard coded to full duplex. Iv restarted both devices even tried different switch ports.


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## Cellus (Aug 31, 2006)

Have manual settings been completely set on both the router and the switch? Double-check the settings in IOS as it is most likely the culprit.


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