The problem resolved.
Final
--------re0--------carp0(re1)
ISP1----[OpenBSD+CARP]----\ SWI _____CISCO<<<-----LAN
ISP2----[OpenBSD+CARP]---- /TCH-------Fe0/1
--------re0--------carp0(re1)----\
-----------------------------------PC
re1:
10.0.0.1
re1:
10.0.0.2
carp0:
10.0.0.17/28
Fe0/1:
10.0.0.18/28
On both OpenBSD machines.
Code:
arp -s 10.0.0.18 MAC_ADDRESS permanent
On CISCO router (configuration terminal):
Code:
arp 10.0.0.17 0100.5e00.0101 arpa
ip route 0.0.0.0 0.0.0.0 FastEthernet4 10.0.0.17 permanent