HSRP, VRRP, GLBP, and IP SLA
First-hop redundancy protocols provide a stable default gateway while real routers fail, recover, or lose upstream reachability. netverdict models HSRP, VRRP, GLBP, IP SLA, and object tracking for failover labs.
Support level
Section titled “Support level”| Area | Level | Notes |
|---|---|---|
| HSRP | Supported | Active/standby election, virtual IP/MAC, priority, preempt, tracking. |
| VRRP | Supported | Master/backup election, IPv4 and IPv6 surfaces. |
| GLBP | Behaviour model | AVG/AVF style behaviour for supported scenarios. |
| IP SLA | Behaviour model | Probe result feeds object tracking. |
| Object tracking | Supported | Priority decrement and failover triggers. |
Standards coverage
Section titled “Standards coverage”| Standard | Coverage | Notes |
|---|---|---|
| RFC 2281 | Behaviour model | HSRP-style gateway redundancy. |
| RFC 5798 | Behaviour model | VRRPv3 including IPv6 concepts. |
| Cisco GLBP | Behaviour model | AVG/AVF concepts. |
| Cisco IP SLA | Behaviour model | Probe and tracking semantics. |
Feature matrix
Section titled “Feature matrix”| Feature | Status | Notes |
|---|---|---|
| HSRP group | Supported | Interface group config. |
| HSRP priority/preempt | Supported | Determines active router. |
| HSRP tracking | Supported | Priority decrement based on tracked object. |
| VRRP virtual address | Supported | IPv4 and IPv6 forms where parsed. |
| VRRP priority | Supported | Master election. |
| GLBP AVG/AVF | Behaviour model | Gateway/load-sharing concept. |
| IP SLA icmp-echo | Supported | Tracks reachability. |
| Track object | Supported | Feeds HSRP/VRRP decisions. |
Vendor command matrix
Section titled “Vendor command matrix”| Command | IOS-style | Junos-style | VyOS-style | Notes |
|---|---|---|---|---|
standby 10 ip 10.0.10.1 | Supported | n/a | n/a | HSRP virtual IP. |
standby 10 priority 110 | Supported | n/a | n/a | Election priority. |
standby 10 preempt | Supported | n/a | n/a | Preemption. |
vrrp 10 ip 10.0.10.1 | Supported | Partial | Partial | VRRP virtual IP. |
no vrrp 7 | Supported | n/a | Supported | Interface-level VRRP group removal for IOS/IOS-XE and NX-OS-style trees. |
glbp 10 ip 10.0.10.1 | Partial | n/a | n/a | GLBP group. |
ip sla 1 | Supported | n/a | Partial | Probe definition. |
show standby brief | Supported | n/a | n/a | HSRP state. |
show vrrp brief | Supported | Partial | Partial | VRRP state. |
Behaviour notes
Section titled “Behaviour notes”Elections are deterministic. Priority wins, then stable tie-breaks are used. Tracking changes are applied as events, so a replayed failure has the same gateway transition.
Examples
Section titled “Examples”Canonical example
configure terminalinterface Vlan10 ip address 10.0.10.2 255.255.255.0 standby 10 ip 10.0.10.1 standby 10 priority 110 standby 10 preempt standby 10 track 1 decrement 30ip sla 1 icmp-echo 192.0.2.1track 1 ip sla 1 reachabilityendshow standby briefVendor styles
IOS-style
interface Vlan10 standby 10 ip 10.0.10.1 standby 10 priority 110 standby 10 preempt standby 10 track 1 decrement 30Junos-style
set interfaces irb unit 10 family inet address 10.0.10.2/24 vrrp-group 10 virtual-address 10.0.10.1set interfaces irb unit 10 family inet address 10.0.10.2/24 vrrp-group 10 priority 110VyOS-style
set high-availability vrrp group VLAN10 interface eth1set high-availability vrrp group VLAN10 virtual-address 10.0.10.1/24set high-availability vrrp group VLAN10 priority 110Known limits
Section titled “Known limits”Authentication packets, GLBP weighted load-balancing fidelity, sub-second timer quirks, and every vendor message/state label are simplified.