carp and arp_rtrequest: bad gateway 1.1.1.5 (!AF_LINK)

[c0re]

I got 2 servers with CARP enabled. One is MASTER, second - BACKUP.
CARP is for HA of running some service on that servers.

All works fine, but today I've got interesting case:
Service was not responding for 5 minutes. Can't tell more details
because it was said by not IT guy.

Okay, I went to check logs on master and backup servers. All was fine
except dmesg and messages:

Master server has no recored in messages for about 1 hour.

But on slave server I saw that:

Oct 20 12:15:00 carp-backup kernel: arp_rtrequest: bad gateway 1.1.1.5
(!AF_LINK)
Oct 20 12:15:00 carp-backup kernel: arp_rtrequest: bad gateway 1.1.1.6
(!AF_LINK)
Oct 20 12:15:00 carp-backup kernel: arp_rtrequest: bad gateway 1.1.1.9
(!AF_LINK)
..................
Oct 20 12:49:58 carp-backup kernel: arp_rtrequest: bad gateway 1.1.1.5
(!AF_LINK)
Oct 20 12:49:58 carp-backup kernel: arp_rtrequest: bad gateway 1.1.1.6
(!AF_LINK)
Oct 20 12:49:58 carp-backup kernel: arp_rtrequest: bad gateway 1.1.1.9
(!AF_LINK)

Total about 300 records.

Can anyone comment something about it? What was that? Backup server
was loosing connectivity with Master server?

In sysctl.conf I've got only net.inet.carp.preempt=1.Now I tuned log
to net.inet.carp.log=2. This should log carp info messages.

Am I right about loosing connectivity between master-backup servers or
there can be another reason?