Tek-Tips is the largest IT community on the Internet today!
Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!
-
Congratulations Mike Lewis on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!
udld port aggressive
- Thread starter laydog
- Start date
jimbopalmer
Programmer
Looks like it helps with auto negotiation mishaps.
"Configuring UniDirectional Link Detection
One best practice to follow when configuring a network like the one used in this chapter is the configuration of UniDirectional Link Detection (UDLD) in Aggressive mode. UDLD is designed to mitigate certain fault conditions on fiber and copper Ethernet interfaces. UDLD is designed to shutdown any miswired ports or unidirectional links by putting the port in an errDisabled state. UDLD is a Layer 2 protocol and, when run in combination with autonegotiation Layer 1 mechanisms, UDLD can validate the physical (Layer 1) and logical (Layer 2) integrity of a link. UDLD accomplishes this task by learning about neighbors and keeping neighbor status in a cache. Neighbors are learned by the sending of UDLD echo or hello messages.
The UDLD Aggressive feature provides additional protection against unidirectional link conditions in certain situations, and attempts to re-establish a connection with the neighbor when a failure is detected. UDLD Aggressive works by detecting when one side of a link remains up while the other side of the link has gone down, and after eight failed retries, transitions the port to an errDisabled state and generates a syslog message.
Cisco recommends configuring UDLD in Aggressive mode on point-to-point FastEthernet/GigabitEthernet links between Cisco switches, and setting the message interval to 15 seconds. UDLD is globally disabled by default and can be enabled globally or on a port–by-port basis. In the examples in this section, UDLD Aggressive should be configured on all the links between switches." -
I tried to remain child-like, all I acheived was childish.
"Configuring UniDirectional Link Detection
One best practice to follow when configuring a network like the one used in this chapter is the configuration of UniDirectional Link Detection (UDLD) in Aggressive mode. UDLD is designed to mitigate certain fault conditions on fiber and copper Ethernet interfaces. UDLD is designed to shutdown any miswired ports or unidirectional links by putting the port in an errDisabled state. UDLD is a Layer 2 protocol and, when run in combination with autonegotiation Layer 1 mechanisms, UDLD can validate the physical (Layer 1) and logical (Layer 2) integrity of a link. UDLD accomplishes this task by learning about neighbors and keeping neighbor status in a cache. Neighbors are learned by the sending of UDLD echo or hello messages.
The UDLD Aggressive feature provides additional protection against unidirectional link conditions in certain situations, and attempts to re-establish a connection with the neighbor when a failure is detected. UDLD Aggressive works by detecting when one side of a link remains up while the other side of the link has gone down, and after eight failed retries, transitions the port to an errDisabled state and generates a syslog message.
Cisco recommends configuring UDLD in Aggressive mode on point-to-point FastEthernet/GigabitEthernet links between Cisco switches, and setting the message interval to 15 seconds. UDLD is globally disabled by default and can be enabled globally or on a port–by-port basis. In the examples in this section, UDLD Aggressive should be configured on all the links between switches." -
I tried to remain child-like, all I acheived was childish.
- Status
Similar threads