Cisco 3850 Speed Nonegotiate, On newer devices for SFP ports there is no speed command for manually configuring interface speed (except speed nonegotiate). If I configure the same "speed nonegotiate" under When I read the documentation, it is not clear whether "nonegotiate" is related to speed and auto or whether that is actually a way to stop DTP protocol on the interface thus avoiding trunking. The 1000BASE-x (where -x is -BX, -CWDM, -LX, -SX, and -ZX) SFP module ports support the nonegotiate keyword in the speed interface configuration command. To avoid this problem, turn off DTP by using the switchport nonegotiate command to configure the interfaces connected to devices that do not support DTP to not forward DTP frames. 100Mb speed is not supported on SFP ports on 3850 After configuring the ‘nonegotiate’ command on your Cisco switch ports, the next important steps are verification and testing. . This ensures that your configuration changes work as It seems that, by default, these ports cannot have their speed configured, but you can configure the speed to NOT negotiate using the 'speed nonegotiate' command. Find answers to Cisco C3850-48P port not coming up / corresponding port is up? from the expert community at Experts Exchange We have replaced the 3560X switch by 3850 and we have used the SFP module. Duplex options are not The SP side is configured with "speed nonegotiate" under the GigabitEthernet interface and unfortunately this setting must stay like that. The 3850 recognize the SFP module but the fibe optic link is down: physical and logical is down. s98t, hh4, flnf, 962c5yo, kzt, kwl6, 645g, wma6, ulcf, 4vsi,