Force mode configuration syntax

To change the port speed of interface 1/1/8 from the default of 10/100/1000 auto-sense to 10 Mbps operating at full-duplex, enter the following. 

device(config)# interface ethernet 1/1/8
device(config-if-e1000-1/1/8)# speed-duplex 10-full

Force Mode Configuration Considerations

The following considerations apply to the force mode configuration.

  • When a local partner issues a speed-dup 100-full or speed-dup 10-full command, if the remote partner does not issue the same commands it becomes 100-half or 10-half, and may receive collision errors. The local partner may receive InErrors such as CRC, Fragment or Bad packets.
  • When a local partner issues a speed-dup 100-full or speed-dup 10-full command, if the remote partner issues the same command, the port may or may not come up, since both sides enter the force mode and want to force the partner to accept these conditions. If both sides come up, they may not receive any In or Out Errors.

  • When a local partner is a force mode configuration such as 100-full/half or 10-full-half and the remote partner is also a force mode configuration, if another force mode in a local or remote partner such as 10-full is entered, the remote or local partner link may or may not come up. This is an IEEE force mode standard. To resolve force mode changing, it is recommended that you change to auto mode first on one side before switching to another force mode configuration.

Parent topic: Force mode configuration