Question about ISC-dhcp, subnet and options

[Ulf Zimmermann]

I have a question about options inside of subnet definations. Part of my config is below:

# VLAN 52 - 10.1.1.0/24
subnet 10.1.1.0 netmask 255.255.255.0 {
        authoritative;
        option routers                  10.1.1.1;
        option subnet-mask              255.255.255.0;
        option domain-name              "example.com";
        option domain-name-servers      10.2.0.5, 10.2.0.6;
        option netbios-name-servers     10.3.0.71, 10.3.0.72;

        option time-offset              -28800; # Pacific Standard Time
        option ntp-servers              10.3.0.69, 10.4.0.40;

        # PXE Kickstart section to be included from file
        include "/etc/dhcp/includes.fremont/kickstart-10.1.1.0-24.conf";

}

# VLAN  2 - Network Management 10.3.0.0/22
subnet 10.3.0.0 netmask 255.255.252.0 {
        authoritative;
        option routers                  10.3.0.1;
        option subnet-mask              255.255.252.0;
        option domain-name              "example.com";
        option domain-name-servers      10.2.0.5, 10.2.0.6;
        option netbios-name-servers     10.3.0.71, 10.3.0.72;

        option time-offset              -28800; # Pacific Standard Time
        option ntp-servers              10.3.0.69, 10.4.0.40;
        default-lease-time              21600; # 6 hours
        max-lease-time                  43200; # 12 hours

        class "pxeclients" {
                match if substring(option vendor-class-identifier, 0, 9) = "PXEClient";
                next-server 10.3.0.12;
                filename "pxelinux.0";
                #if not exists gpxe.bus-id {
                #       filename "/gpxelinux.0";
                #}
        }

        # Kickstart config file for 10.3.0.0/22
        include "/etc/dhcp/includes.fremont/kickstart-10.3.0.0-22.conf";

        # Static IP assignments via DHCP
        include "/etc/dhcp/includes.fremont/static-10.3.0.0-22.conf";

        # Include the iLO config file for 10.137.8.0/22
        include "/etc/dhcp/includes.fremont/ilo-10.3.0.0-22.conf";

}

# VLAN 10 - Corporate - 10.5.0.0/22
subnet 10.5.0.0 netmask 255.255.252.0 {
        authoritative;
        option routers                  10.5.0.1;
        option subnet-mask              255.255.252.0;
        option domain-name              "example.com";
        option domain-name-servers      10.2.0.5, 10.2.0.6;
        option netbios-name-servers     10.3.0.71, 10.3.0.72;

        option time-offset              -28800; # Pacific Standard Time
        option ntp-servers              10.3.0.69, 10.4.0.40;
        default-lease-time              21600; # 6 hours
        max-lease-time                  43200; # 12 hours

        # Kickstart config file for 10.5.0.0/22
        include "/etc/dhcp/includes.fremont/kickstart-10.5.0.0-22.conf";

        # Static IP assignments via DHCP
        include "/etc/dhcp/includes.fremont/static-10.5.0.0-22.conf";

}

The problem I am running into is that on the VLAN 52 I am getting the following response from dhcpd:

10:47:24.273532 IP (tos 0x0, ttl 63, id 60694, offset 0, flags [none], proto UDP (17), length 576)
    10.8.0.165.bootps > 10.3.0.21.bootps: BOOTP/DHCP, Request from 00:50:56:aa:46:c5, length 548, hops 1, xid 0x57aa46c5, secs 4, Flags [Broadcast]
          Gateway-IP 10.1.1.1
          Client-Ethernet-Address 00:50:56:aa:46:c5
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Discover
            Parameter-Request Option 55, length 24: 
              Subnet-Mask, Time-Zone, Default-Gateway, IEN-Name-Server
              Domain-Name-Server, RL, Hostname, BS
              Domain-Name, SS, RP, EP
              Vendor-Option, Server-ID, Vendor-Class, BF
              Option 128, Option 129, Option 130, Option 131
              Option 132, Option 133, Option 134, Option 135
            MSZ Option 57, length 2: 1260
            GUID Option 97, length 17: 0.66.42.10.5.180.105.222.121.213.164.28.115.149.149.224.89
            ARCH Option 93, length 2: 0
            NDI Option 94, length 3: 1.2.1
            Vendor-Class Option 60, length 32: "PXEClient:Arch:00000:UNDI:002001"
10:47:24.273997 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 328)
    10.3.0.21.bootps > 10.1.1.1.bootps: BOOTP/DHCP, Reply, length 300, hops 1, xid 0x57aa46c5, secs 4, Flags [Broadcast]
          Your-IP 10.1.1.30
          Server-IP 10.3.0.155
          Gateway-IP 10.1.1.1
          Client-Ethernet-Address 00:50:56:aa:46:c5
          file "/rhel6server-x86_64/pxelinux.0"
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Offer
            Server-ID Option 54, length 4: 10.3.0.21
            Lease-Time Option 51, length 4: 21600
            Subnet-Mask Option 1, length 4: 255.255.252.0
            Time-Zone Option 2, length 4: -28800
            Default-Gateway Option 3, length 4: 10.3.0.1
            Domain-Name-Server Option 6, length 8: 10.2.0.5,10.2.0.6
            Domain-Name Option 15, length 8: "autc.com"

The problematic parts are:

            Subnet-Mask Option 1, length 4: 255.255.252.0
            Default-Gateway Option 3, length 4: 10.3.0.1

Shouldn't this return 255.255.255.0 and 10.1.1.1 based on the above subnet declaration? Should the "options routers" and "options subnet-mask" be local to the subnet declaration?

Ulf.