• Author : Saurav Arora


Head-End-Replicated DHCP Packets Suppression in VXLAN Network

Description In VXLAN networks, broadcast DHCP requests are head-end-replicated to all VXLAN tunnel endpoints (VTEP). If a DHCP relay helper address is configured on more than one VTEP, each such VTEP relays the DHCP request to the configured DHCP server. This could potentially overwhelm the DHCP server as it would receive multiple copies of broadcast packets originated from a host connected to one of the VTEPs. In Figure 1, a DHCP request from DHCP Client1 is head-end-replicated to all VTEPs. DHCP Relay on VTEPs B and C will also forward this request to the DHCP server, resulting in three copies...
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Multipath-Relax with As-Path Weights

Description Term multipath-relax in the context of BGP bestpath selection process means that the “AS-path” contents of BGP paths are not compared during the best path selection algorithm execution. This essentially means that the BGP paths with same AS-path lengths shall be considered equal cost irrespective of whatever the AS-path content is.    The “AS-path” content comparison is controlled by an existing CLI knob “bgp bestpath as-path multipath-relax” which is enabled by default. This CLI knob, when disabled, inserts a new bestpath step at number 8 into the bestpath selection algorithm which does the as-path content comparison to choose a...
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BGP neighbor default-originate always

Description Neighbor default-originate feature is used to advertise a default route to the neighbor ( peer or peer-group ) even when a default route is not present in the BGP RIB. If a default route is present in the BGP RIB, this route will be advertised to the neighbor. When a default route is not present in the BGP RIB, one will be artificially generated and advertised to the neighbor for which this feature is configured. This artificially generated default route will not be installed in the BGP RIB. The default-route ( existing in BGP RIB or artificially generated )...
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