Streaming video stops - the fix (if you have DD-WRT)

[ladr]

When I first got Fusion service, I loved it until I found that streaming video would stop every few minutes.

It turns out that what was happening was that Sonic renews it's DHCP leases every 5 minutes, and the renewal message was being blocked by the built in firewall of my DD-WRT router. So rather than properly renewing, the lease would expire and the video would drop while a new lease was being set up.

The fix is to allow those messages through:

add a rule to specifically allow those messages. Do this by navigating within your router’s interface to Administration > Commands, and entering the following into the Commands fields:

iptables -I INPUT 2 -p udp --sport 67 --dport 68 -j ACCEPT

Finally, press the Save Firewall button to save the rule to be executed whenever the router is restarted.

Credit: http://yllus.com/2011/03/25/fix-my-dd-w ... dhcp-lease

[parkerday]

Another DD-WRT command I find helpful is one that allows access to the modem through the router. For example, if you try to go to 192.168.1.254 (common DSL modem IP) you won't get anything, but...

Save this command to Startup:
ifconfig `nvram get wan_ifname`:0 192.168.1.2 netmask 255.255.255.0

Save this command to Firewall:
iptables -t nat -I POSTROUTING -o `nvram get wan_ifname` -j MASQUERADE

...and you'll be able to access your bridged modem at 192.168.1.254 through your router. It's really handy for checking sync rates and other modem stats. There is a good explaination of it here (along with modifications that may be needed to the commands):
http://www.dd-wrt.com/wiki/index.php/Ac ... figuration

[jmunowitch]

Thank you, this looks like a great piece of info. I will have to try this when I get home.

This could be why my VPN drops off seemingly randomly when I am on my home connection.

[mitsuko3]

I found your article on the video stops although I have a similar issue with Cisco Linksys E2500.
I went to Cisco Linksys support but the warranty expired and they want me to pay for the support service.
I went to the router and could not find Administration > Commands, and entering the following into the Commands fields: I do not see the commands.
Appreciate any help on this.

[dane]

I wish someone would submit this as a patch to DD-WRT. This bug has existed for some years, and it's quite an annoyance for folks who use the tool.

[hfidek]

omg i have strugle with that same problem for ever with ddwrt and the linksys 2500.

[digitalbitstream]

++ great info.
And I filed a bug report with DD-WRT, but don't hold your breath: http://svn.dd-wrt.com/ticket/3077

[BrainSlayer]

opening the port just for fun is a security flaw. remember, anyone can send renewal requests to a wan port, not just in isp based environments. normally a initial dhcp request is returns with a new ip information which also contains the lease time. if time is over, the dhcp client will renew itself without any request from the isp. so the dhcp server on isp side is wrong configured. if i just open this port, it would make alot of fun to get alot of people into trouble just by sending fake renewal requests to routers with bad ip configurations

[digitalbitstream]

BrainSlayer : you appear be one of the voices blocking a fix for this issue on the DD-WRT side.

It's hardly "fun" to open the port. It's needed only to be able to download a file that takes longer than 5 minutes, eh?
If the firewall solution is wrong, what a solution do you recommend?
And how can this be a security hole if the router, which is the DHCP client, processes the DHCPOFFER?
DD-WRT *is* the client: why is it not renewing the lease at 50% of the lease time (2.5 minutes in the case)?

[jon]

For the record, I'm using DD-WRT and am NOT seeing a lease-renewal problem. Using DD-WRT's Status->WAN
display, I can see the lease being renewed by DD-WRT half-way through the 5-minute lifetime.

Setup: Sonic Fusion with a dynamic IP address.

Modem is an Actiontec GT701D in bridge mode.

Router is a Linksys WRT54G v8.2 running DD-WRT v24-sp1_micro_generic 7/27/08, with
a dhcp client on the wan side. I've not changed its iptables settings, and didn't see any
dhcp-related rules (udp port 67 or 68) in a listing of its iptables.