Arista BGP Tips - ECMP, RR, Active Prefix

If the following 6 attributes of paths are identical, they are considered as equal paths:

• Weight
• Local_Pref
• AS_Path
• Origin
• MED
• IGP cost to NH

BGP RR

• ONLY RR knows who is RRC, RRC has no idea
• Originator ID is assigned by originating router
• RR changes nothing, but add Cluster ID

Active BGP Prefix

• show ip bgp vrf all, some prefixes are valid but not active
• the common reason is, this particular prefix is learned from other routing protocols
• that's why we need the knob - "bgp advertise-inactive"