I have a firewall environment using two HP ML 110 G6, and carp is happening but some behaviors strangers.

I have the following interfaces

bge0 -> WAN
re0_vlan34 -> DMZ1  (re0)
re0_vlan36 -> DMZ2  (re0)
re1 -> pfsync

and created the following interfaces carp's

vip1  177.x.x.1    MASTER
vip2  172.16.102.100 MASTER
vip3  172.16.103.100 MASTER

node01
wan:  177.x.x.2
dmz1: 172.16.102.101
dmz2: 172.16.103.101

node02
wan:  177.x.x.3
dmz1: 172.16.102.102
dmz2: 172.16.103.102

pfsync this interface with the following address 172.16.100.0/30

node01
pfsync: 172.16.100.1
node02
pfsync: 172.16.100.2

I have the environment working properly but that the overthrow node01 is the master that node02 the slave is assumed to master properly, but when he takes node01 back as master only the interface wan anyone have any idea what could be the problem

vip1: flags=49 <up,loopback,running>metric 0 mtu 1500
        inet 177.x.x.1 netmask 0xffffff00
        carp: MASTER vhid 1 advbase 1 advskew 100
vip2: flags=49 <up,loopback,running>metric 0 mtu 1500
        inet 172.16.102.100 netmask 0xffffff00
        carp: BACKUP vhid 2 advbase 1 advskew 100
vip3: flags=49 <up,loopback,running>metric 0 mtu 1500
        inet 172.16.103.100 netmask 0xffffff00
        carp: BACKUP vhid 3 advbase 1 advskew 100

What is the default behavior of CARP. We master and backup if the master down the backup takes over, and when the master takes him back again or he is as a backup?

Regards</up,loopback,running></up,loopback,running></up,loopback,running>