HA Architecture – Links
HA1 (control link), HA1 backup, Heartbeat backup
- Config synchronization
- Management plane runtime state synchronization
- FIB, user-group mappings, DHCP leases, DNS cache, etc.
- HA state communication
HA2 (data link) & HA2 backup
- Session synchronization
- A/P – We do not sync ICMP sessions.
- A/A – We do not sync Multicast sessions.
- Data plane runtime state synchronization.
- ARP table, Neighbor table, user-IP mappings, etc.
- You cannot ping the HA2 interface
HA3
- Packet forwarding link (Active/Active only)
- Supports link aggregation.
HA Architecture – Active/Passive States
- Initial – Booting up.
- Active – Processes all traffic.
- Passive – Backs up active device.
- Non-functional – Device in recovery from the path, link, or task failure.
- Suspend – Administrative deactivation or excessive flapping
