At the same time, the firewall logs now show some DHCP traffic blocked. Specifically, one or two of my DHCP servers (on the WAN) are trying to reach my LAN address. It's port 67/udp on both ends of the attempted connection. Here are the log entries:
Get Started | Barracuda Campus Jan 07, 2020 Cisco ASA Series Command Reference, A - H Commands - dhcpd May 12, 2020 Firewall rule needed for DHCP ? | Netgate Forum I've enabled DHCP relay on the various VLAN interfaces, and specified the IP of our internal DHCP-server. But, in order to get DHCP working I had to add the following rule on the subnet where the DHCP-server lives : UDP 0.0.0.0 68 255.255.255.255 67 * Permit DHCP CentOS 7 : Firewalld : Server World
I am not getting an IP in the subnet 10.0.0.0/24 where the DHCP is working and should serve an IP, I am getting instead only an IP in the subnet 169.254.0.0/16(link local address) that is probably given by Windows which runs on the laptop I am using to test this, which makes me think it might be a problem of the network firewall blocking the DHCP Discovery service.
There is an option to overrule that, but it is not available for outbound rules. Hence, to allow DHCP client broadcasts, you will have to exclude them from the rule suggested in this answer, assuming this firewall rule is indeed responsible for breaking your DHCP setup. DHCP clients use the remote UDP port 67 for IPv4 and 547 for IPv6. Need help to allow traffic through firewall to DHCP server Need help to allow traffic through firewall to DHCP server I assume the source should be ASA1 outside interface ip address and destination is what you configured as the relay server. Port …
Dec 08, 2016
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