D-Link DGS-6600-48T Product Manual - Page 77

DGS-6604 bgp always-compare-med bgp always-compare-med Use this command to compare the Multi-Exit Discriminator (MED) for paths from neighbors in different autonomous systems. Use the no bgp always-comparemed command to disallow the comparison. bgp always-compare-med no bgp always-compare-med Syntax None Default Disabled Command Mode Router configuration Usage Guideline The MED, as stated in RFC 1771, is an optional nontransitive attribute that is a four octet non-negative integer. The value of this attribute may be used by the BGP best path selection process to discriminate among multiple exit points to a neighboring autonomous system. The MED is one of the parameters that is considered when selecting the best path among many alternative paths. The path with a lower MED is preferred over a path with a higher MED. During the best-path selection process, MED comparison is done only among paths from the same autonomous system. The bgp always-compare-med command is used to change this behavior by enforcing MED comparisons between all paths, regardless of the autonomous system from which the paths are received. Example The bgp deterministic-med command on page 75 can be configured to enforce a deterministic comparison of the MED value between all paths received from within the same autonomous system. This example shows how to configure the comparison of the MED from alternative paths, regardless of the autonomous system from which the paths are received: Switch(config)# router bgp 65534 Switch(config-router)# bgp always-compare-med CLI Reference Guide 67