OK - I know this isn't strictly a linux problem (though it may be) but someone here may be able to help,
I have an odd problem with port forwarding through a linksys WRT120N router. My network looks like this:
outside - Cisco ADSL - DMZ - Linksys - inside
The DMZ net is 192.168.1.0/24 inside is 192.168.10.0/24
The DMZ has two debian ARM boxes on it, inside has several different debian/ubuntu boxes, but crucially has my dnsmasq DNS server on 192.168.10.50. That server lists all my local machines. The linksys has NAT turned on. It also allows port forwarding of both TCP and UDP on port 53 from the outside (i.e. the DMZ) to 192.168.10.50.
Now the wierd bit.
DNS lookups from the DMZ to the inner server through the linksys only work once every 4-5 minutes. So if I fire up nslookup or use dig to resolve any of my internally named servers I can do it immediately, but then get "connection timed out; no servers could be reached" for the next 4 or five minutes whereafter I can again resolve a host.
Can someone please suggest what may be going on? Anyone else using a WRT120N? I can't find anything on the obvious forums. (And yes I know I could move the DNS server to the DMZ......)
Mick
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The text file for RFC 854 contains exactly 854 lines. Do you think there is any cosmic significance in this?
Douglas E Comer - Internetworking with TCP/IP Volume 1
http://www.ietf.org/rfc/rfc854.txt ---------------------------------------------------------------------