pfSense

When you have custom options defined on multiple interfaces, only the first interface is handled correctly. Example config:

 <dhcpd>
                <lan>
                        <enable/>
                        <range>
                                <from>192.168.1.10</from>
                                <to>192.168.1.245</to>
                        </range>
                        <defaultleasetime/>
                        <maxleasetime/>
                        <netmask></netmask>
                        <failover_peerip/>
                        <gateway/>
                        <domain/>
                        <domainsearchlist/>
                        <ddnsdomain/>
                        <tftp/>
                        <ldap/>
                        <next-server/>
                        <filename/>
                        <rootpath/>
                        <numberoptions>
                                <item>
                                        <number>128</number>
                                        <value>VLAN-A=100;</value>
                                </item>
                        </numberoptions>
                </lan>
                <opt2>
                        <range>
                                <from>172.16.100.100</from>
                                <to>172.16.100.200</to>
                        </range>
                        <defaultleasetime/>
                        <maxleasetime/>
                        <netmask/>
                        <failover_peerip/>
                        <gateway/>
                        <domain/>
                        <domainsearchlist/>
                        <enable/>
                        <ddnsdomain/>
                        <tftp>111.222.111.222</tftp>
                        <ldap/>
                        <next-server/>
                        <filename/>
                        <rootpath/>
                        <numberoptions>
                                <item>
                                        <number>2</number>
                                        <value>-18000</value>
                                </item>
                        </numberoptions>
                        <ntpserver>172.16.100.1</ntpserver>
                </opt2>
        </dhcpd>

Results in dhcpd.conf:

option ldap-server code 95 = text;
option domain-search-list code 119 = text;
option custom-opt-0 code 128 = text;
option custom-opt-1 code 2 = text;

default-lease-time 7200;
max-lease-time 86400;
log-facility local7;
ddns-update-style none;
one-lease-per-client true;
deny duplicates;
ping-check true;
authoritative;
authoritative;
subnet 192.168.1.0 netmask 255.255.255.0 {
        pool {
                range 192.168.1.10 192.168.1.245;
        }
        option routers 192.168.1.1;
        option domain-name-servers 192.168.1.1;

        option custom-opt-0 "VLAN-A=100;";
}
subnet 172.16.100.0 netmask 255.255.255.0 {
        pool {
                range 172.16.100.100 172.16.100.200;
        }
        option routers 172.16.100.1;
        option domain-name-servers 172.16.100.1;
        option ntp-servers 172.16.100.1;
        option tftp-server-name "111.222.111.222";

        option custom-opt-0 "-18000";

}