14.1. VRRP

You can find the VRRP Settings at General → Virtual IPs.

A VRRP IP is an IP that can also be shared with different machines. The master always holds the address, one or more secondary machines will be on standby and get the address if the Master is not online anymore.

All VRRP enabled machines communicate over multicast on the interface they are defined on. If a machine is not receiving multicasts from its neighbors it will assume the master role in order of their configured priority.

VRRP uses the following destination IPs:

Note

  • IPv4: 224.0.0.18
  • IPv6: fe02::12

You can configure the Priority on the screen. The highest available number is always the Master.

A password must also be configured. It must match on all machines that share the address.

Track Interface might be used to override the trackable interface for this VRRP IP. This is useful if you have a VRRP on top of a Bridge interface. The bridge itself only goes offline when all the interfaces are offline. This allows you to pin the failover event to a specific interface. By default it is always pinned to the underlying interface of the settings.

14.2. IP Alias

You can find the Virtual IP Settings at General → Virtual IPs.

An IP Alias is an additional IP on one of the interfaces.

You can define any IP you like, you have to consider though that the IP Netmask is 32.