Cisco-Linksys doesn't like ISC-DHCP3 (3.1.1)

[Will Eagleton]

I work for an ISP with about 8000 customers, we run embedded headless Linux boxes with Ubuntu 9.04 and isc-dhcp3-server 3.1.1

Searching the internet for several days, and playing with options seems to imply there have been issues with 3.x.x ISC-DHCP3 server as well as Linksys -by far, mostly Linksys routers since at least 2007.

Not all Linksys have problems working with our implementation of isc-dhcp3-server (3.1.1 on old Ubuntu 9.04), but many do. I have one particular customer that I'm experimenting with currently, here is the tcpdump:


12:51:45.584597 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 328) 0.0.0.0.bootpc > 255.255.255.255.bootps: [udp sum ok] BOOTP/DHCP, Request from 58:6d:8f:79:8c:9d (oui Unknown), length 300, xid 0x1909bf18, Flags [Broadcast] (0x8000)
          Client-Ethernet-Address 58:6d:8f:79:8c:9d (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Discover
            Hostname Option 12, length 19: "Fogelmania_unit1409"
            Parameter-Request Option 55, length 4:
              Subnet-Mask, Default-Gateway, Domain-Name, Domain-Name-Server
            END Option 255, length 0
            PAD Option 0, length 0, occurs 29

12:51:46.000652 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 328) x.199.21.84.web-pass.com.bootps > 255.255.255.255.bootpc: [udp sum ok] BOOTP/DHCP, Reply, length 300, xid 0x1909bf18, Flags [Broadcast] (0x8000)
          Your-IP x.199.87.85.web-pass.com
          Server-IP x.199.21.84.web-pass.com
          Client-Ethernet-Address 58:6d:8f:79:8c:9d (oui Unknown)
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Offer
            Server-ID Option 54, length 4: x.199.21.84.web-pass.com
            Lease-Time Option 51, length 4: 28800
            Subnet-Mask Option 1, length 4: 255.255.255.224
            Default-Gateway Option 3, length 4: x.199.87.85.web-pass.com
            Domain-Name Option 15, length 12: "web-pass.com"
            Domain-Name-Server Option 6, length 12: ns6.web-pass.com,x.152.14.204.web-pass.com,ns3.web-pass.com
            END Option 255, length 0
            PAD Option 0, length 0, occurs 4



The head-portion of my dhcpd.conf

authoritative;

ddns-update-style none;
option domain-name "web-pass.com";
option domain-name-servers 208.80.68.212, 204.14.152.2, 204.14.152.5;

default-lease-time 28800;
max-lease-time 57600;
authoritative;
log-facility local7;
always-broadcast off; 
 # 'on' caused a loop with 00:1d:ba:23:ac:4d (DIR-601) via eth0

We have issues with even the e4200 which was a relatively new router out of the Cisco-Linksys camp, has anyone ran into this issue repeatedly and/or resolved it? Some routers/firmware work fine, others dont, so this is not a consistent issue. I've seen reference to 3.1.1 having issues, but Linksys... many issues.

Thoughts?

Best,
-Will