When using auto detection the SFP ports on LANCOM switches can only detect the SFP module. No negotiation is done between the two connected switches. If for example a switch with a 10 GBit SFP+ module is connected to a switch with a 1 GBit SFP module the link cannot be established. Therefore the link speed must be set to a fixed value (the same value on both switches).

This article describes how the speed for the SFP ports can be set on GS-23xx, GS-3xxx or XS as well as GS-45xx series switches.

Make sure, that access to the management IP address of the device is possible via another or an additional port. If a connection via the SFP port cannot be established, access to the switch is still possible.

The port configuration has to be made before plugging in the SFP module.



GS-23xx series:

Go to the menu Configuration → Port → Configuration and set the speed for the SFP port (ports 23 - 26) under Speed - Configured.

GS-3xxx series:

1) Go to the menu System → Port Management → Port Configuration.

2) Set the speed for the used SFP port under Mode (ports 25 - 28).

XS and GS-45xx series:

1) Go to the menu System → Port → Summary → Port Summary and click the checkbox of a SFP port (ports 1 - 8) to edit its settings.

2) Check the checkbox Speed and select a port speed.

When configuring stacking the stacking ports can be operated exclusively with the native port speed. Therefore with stacking it is not possible to use an SFP module with a lower speed than the native port speed on these ports (e.g. a 1 GBit SFP module on a 10 GBit port).