[compunerd632]

I am using a Netgear WNDR3300 with the recommended DD-WRT v24 build 13064. I just got it a week ago and am still working the kinks out.

I noticed today that when I tried to download a few video podcasts that the downloads would simply stop partway through. These are standard HTTP downloads. If I pause and unpause the downloads in the Firefox download manager they would go for a little while longer and then stop again. I previously noticed that behavior on buffering Youtube videos, but attributed it to server load at Youtube, now I'm not so sure.

I found that if I disable the SPI firewall I am able to download the files from start to finish. Any ideas on what may be causing this and how I could solve it without turning the firewall off?

In case it's needed, here's the background on my networking configuration. I have AT&T U-Verse service that provides internet and TV (IP-based). They provide a "residential gateway" (RG) that is necessary for the TV aspect to work. It also provides internet routing, but I wanted to roll my own router so I had more control over the network. I have the WNDR3300 configured as a router and have set it as the DMZ in the RG. The RG actually gives the public IP address to my router - not really sure how it does that, but that's what happens. Based on that, it seems like for all intents and purposes the WNDR3300 is seeing a public internet connection, so I don't understand why there is this trouble downloading files.

[phuzi0n]

Add the iptables rule to your firewall script.

http://svn.dd-wrt.com:8000/dd-wrt/ticket/973

[compunerd632]

Thanks phuzi0n, that appears to have worked! Once you narrowed down the problem area I saw that my DHCP leases were only good for 10 minutes, explaining why I saw the problem so often.

Just curious, why do the default firewall rules block DHCP renewals?

[phuzi0n]

Because half-bridge mode ("DMZplus" on 2wire brand) on certain modems/gateways will send DHCP offers from a different address than the router requests a renewal from. The firewall then blocks the offer because it didn't come from the address it expected.

[Phreaker47]

Wow, thanks SO much for this. My issue was a carbon copy of the OP... being behind a 2wire RG and having the exact same issues. I actually went and bought a new WRT160N just to discover the same problem again... but now that I've found this I have reinstalled my old WRT54G 1.1 and added the IPTABLES command. The problem is gone and I'll get my money back on the new one.

[superflysocal]

[DHC_DarkShadow]

[mudfinger]

I have this exact problem. The link to correct is dead. Does anyone have a valid link?

[JohnnyP]

Here is my firewall script. I ran into the same issue with my motorola dsl This solved it.

iptables -I INPUT -p udp --sport 67 --dport 68 -j ACCEPT

[mudfinger]

so basically you enter the commend into the command shell under admin and "save firewall" and "run command"? this is what i tried and now have an entry under the command shell in a firewall box. just wanted to confirm but i think it is right. BTW it is dd-wrt v24 sp2 (10-10-09 std build) is running on a linksys wrt-54g v2.2.

Thanks

[JohnnyP]

I ran into the same issue using iTunes. The ip address would change every 10 minutes and then the file would drop out and have to be restarted. Putting this in solved it. I think all you need to do is "save firewall" and you should be good to go.

[phuzi0n]