VRRP & GLBP

VRRP — the open one RFC 5798, IP protocol 112, multicast 224.0.0.18, virtual MAC 0000.5e00.01XX, advertisement every 1 s. Master/Backup instead of Active/Standby — and a real IP-owner concept: the device holding the IP can be priority 255. vrrp version 3 adds IPv6. GLBP — the load-balancing one Cisco, UDP 3222, 224.0.0.102. One virtual IP […]

HSRP Deep Dive

Cisco’s classic FHRP: one virtual IP + virtual MAC 0000.0c07.acXX, one Active + one Standby per group. UDP 1985 to 224.0.0.2 (v1, groups 0–255) / 224.0.0.102 (v2, groups 0–4095). Hello 3 / hold 10. interface vlan 10 standby 10 ip 10.10.10.254 standby 10 priority 110 standby 10 preempt standby 10 track 1 decrement 20 ! […]

FHRP Compared — HSRP vs VRRP vs GLBP

First-Hop Redundancy Protocols hand hosts one virtual gateway (VIP + virtual MAC) backed by several routers. Pick by environment: Cisco-only + simple → HSRP · multivendor → VRRP · active load balancing → GLBP HSRP VRRP GLBP Standard Cisco RFC 5798 Cisco Roles Active / Standby Master / Backup AVG / AVF Transport UDP 1985 […]