PXE Boot failed

[chic_cat]

Hi guys...

Have a strange problem:
Using host-only-network
I have
1. The lastest version of Virtual Box with patches
2. Dhcp/DNS server on Centos 6.7

When I install a linux/windows machine from ISO - they all see DHCP server and receiving IP with all parameters.
When I try to make a PXE Boot - linux host can't receive DHCP settings...Log file:

Apr 1 15:44:32 ns1 dhcpd: DHCPDISCOVER from 08:00:27:28:80:c0 via eth3
Apr 1 15:44:33 ns1 dhcpd: DHCPOFFER on 192.168.56.202 to 08:00:27:28:80:c0 via eth3
Apr 1 15:44:34 ns1 dhcpd: DHCPDISCOVER from 08:00:27:28:80:c0 via eth3
Apr 1 15:44:34 ns1 dhcpd: DHCPOFFER on 192.168.56.202 to 08:00:27:28:80:c0 via eth3
Apr 1 15:44:38 ns1 dhcpd: DHCPDISCOVER from 08:00:27:28:80:c0 via eth3
Apr 1 15:44:38 ns1 dhcpd: DHCPOFFER on 192.168.56.202 to 08:00:27:28:80:c0 via eth3
Apr 1 15:44:46 ns1 dhcpd: DHCPDISCOVER from 08:00:27:28:80:c0 via eth3
Apr 1 15:44:46 ns1 dhcpd: DHCPOFFER on 192.168.56.202 to 08:00:27:28:80:c0 via eth3

Any solutions?