I am curious if you would try it out and share on your blog? The router periodically sends out an IGMP membership query to verify that at least one host on the subnet is still interested in receiving traffic directed to that group. This might be because any one of the devices runs an earlier version of Cisco IOS. You can upgrade the Cisco IOS or set the speed and duplex to auto on both devices in order to resolve this. It is not possible to detect the correct duplex mode in the same method that the correct speed can be detected. This implements the policy of always configuring both link partners for the same behavior. Therefore, it is not possible for port 1/1 on switch B to auto-negotiate current behavior. The a prefix on the Duplex and Speed status fields does not always mean that the current behavior is negotiated.

12. Restore the default duplex mode and speed to ports 1/1 on both switches. 1/1 auto Port(s) 1/1 speed set to auto detect. Issue the set port speed 1/1 auto command to configure ports 1/1 on both switches to auto-negotiate. Step 11 shows how to configure the duplex mode on port 1/1 in switch B to half. The switches that run Cisco IOS Software (as opposed to CatOS) default to auto-negotiation for speed and are set to on for the duplex. This output is taken from a Catalyst 6500/6000 that runs Cisco IOS Software Release 12.1(6)E. It shows a connected port that auto-negotiates a link to 100 Mbps and half-duplex. The configuration that runs for this switch has no duplex or speed commands underneath interface FastEthernet 3/1 because auto-negotiation is the default. Duplex is subservient to speed in the sense that if speed is set to auto, then the duplex cannot be manually set.

Therefore, the set port speed 1/1 10 command causes the duplex mode on port 1/1 to be configured as if the command set port duplex 1/1 full is also issued. Now the set port duplex 1/1 half command on switch B works. Issue the set port duplex 1/1 half command to set the mode on port 1/1 in switch A to half. 6. Understand the meaning of the a prefix on the duplex and speed status fields. Issue the show port 1/1 command to examine the status of ports 1/1 on both switches. The show port 1/1 command on switch B shows that the ports is configured for half-duplex and 10 Mb. This example also shows that a link can be successfully connected when there is a mismatch in the duplex modes. A duplex mismatch might or might not result in an error message. You might see cyclic redundancy check (CRC) error messages when both the speed and duplex settings are hardcoded on the two devices.

In addition to the duplex mismatch error message in step 8, you might also see these spanning tree messages when you change the speed on a link. Notice there is no speed or duplex commands under this interface because ! Issue the show interface slot/port command (without the status keyword) to see the port speed and duplex. The show port 1/1 command displays the change in the duplex mode on this port. Issue the set port speed 1/1 10 command to set this speed. The show port 1/1 command on switch B indicates that the port operates at half-duplex and 10 Mb. 1/1 half Port(s) 1/1 set to half-duplex. 1/1 half Port 1/1 is in auto-sensing mode. This step sets the duplex mode to half and speed to 10 on port 1/1 in switch. Sometimes it can mean that the port is not configured for a speed or duplex mode. This indicates that the port operates at 10 Mb in half-duplex mode. This is how switch B determines that port 1/1 operates at 10 Mb.

In this case, where the 1/1 port of switch B is configured for auto-negotiation and the 1/1 port of switch A is not, the 1/1 port of switch B is forced to select the default duplex mode. The previous output from switch B shows duplex as a-half and speed as a-10. This step shows that it is possible for a link partner to detect the speed at which the other link partner operates, even though the other link partner is not configured for auto-negotiation. There is a built in alarm to remind you to scan at a speed it can cope with – a useful feature to save on distortion. There are many ways that can help you pick the best iOS app development company and some of them are listed below. This is one of the most crucial mobile app development challenges that businesses face in their daily working.