The CARP status page located at Status > CARP (failover) shows the current status of all configured CARP Virtual IP addresses. It also provides some controls to enable and disable CARP for troubleshooting and maintenance.
For each VIP, the Interface, Virtual IP, and Status are shown.
The Interface column shows the interface name or identifier for the VIP at the operating system level. This has changed over the years, and currently shows as “_vip” (ex: lan_vip1) on pfSense 2.1.x, and on pfSense 2.2, it shows as “@” (ex: LAN@1).
The Virtual IP column shows the IP address associated with the entry.
The Status column shows MASTER, BACKUP, or INIT, which are:
MASTER: Indicates this node is accepting all traffic for this VIP
BACKUP: Indicates this node is monitoring CARP advertisements and not accepting traffic for the VIP.
INIT: Generally indicates a problem with the VIP. Either the VIP is not configured at the OS level, or the interface upon which it is configured is down or has a problem.
A toggle button at the top of the list will show either Disable CARP or Enable CARP depending on the current status. Disabling CARP will remove the VIPs from the system, and the next available node will take over as MASTER for the CARP VIPs. This setting is not remembered across reboots.
On the primary node, each VIP should show MASTER. On the secondary node, each VIP should show BACKUP. If both nodes show MASTER, there is usually a problem at layer 2 (the switch) preventing the two nodes from seeing each others’ advertisements. See CARP Configuration Troubleshooting.
On pfSense 2.2, in addition to the button to temporarily disable CARP as is found on earlier versions, there is also a toggle button to Enter Persistent CARP Maintenance Mode or Leave Persistent CARP Maintenance Mode. This mode persists across reboots, so it is useful for performing maintenance or upgrades on the primary node such that it does not cause it to take back over prematurely before it is ready.