TomatoUSB

I have an Asus RT-N12 router running Tomato v1.28.9054. It has been working great for a few years. Recently, it started having issues described below, and the problems come up more and more frequently.

1. no outgoing connections through browser or ping.
2. remote desktop from outside the router to a home PC works fine (porting forwarding works).
3. machines on LAN work fine (switch works)
4. web server running behind the router can receive connection from remote clients (port forwarding works)
5. power off the router and power back on temporarily fixes the problem, but the problem became more and more frequent.

My questions are:
Is this a hardware or software problem? If hardware, why can I still connect to it (incoming connections are fine).
If this is firmware problem, why it didn't happen before? Is there a fix?

Thank you very much!

My first though is possibly a DNS issue. I've experienced this before where DNS was incorrectly set (on a server of mine, not router), and all my services like web server and ssh were available from outside, but I could not make any outgoing connections. This was because DNS could not resolve any host names. You could check if you can ping some public IP outside your network, then it's host name to see. Just an idea.
Have you done an nvram reset to try to help?

Thanks for the reply. I kind of doubt this is cmos related because both of my machines behind the router have the same problem, can't make outgoing connection. So I think the problem is at the router. If I power cycle the router, all started working.

I can't ping known servers when the problem happens.

If your pinging "known servers" by ip, but not by name it's dns failing. Try upgrading the firmware to the latest and use dnscrypt, and capture all port 53 requests at the router.

I confirmed that this problem relates to DNS because if I ping the IP of google.com, I can get response, but I can't if I use google.com. How to solve this problem? I believe I have the latest tomato 1.28. Where/how do I use dnscrypt?

Thanks.

If you are using the latest builds dnscrypt is just a check box, at least it is for Shibby.
Try alternate public dns like 8.8.8.8, could be your isp's dns failing. If it works for a while then dies it's probably dnsmasq dying due to some weird setting. Look at the router logs immediately after it fails to get dns reply for errors related to dnsmasq and report the error here?
If your using an older build then upgrade.

Thanks KillerTomato.

I looked at my DNS setting. It was like this:

Use internal DNS (checked)
Use received DNS with user-entered DNS (unchecked)

In the Basic setting page, the static DNS were all set to 0.0.0.0 .

I switched both the above checkboxes (so it doesn't use internal DNS) and also set static DNS to 8.8.8.8 and 8.8.4.4 .

I will report back if there is still problem after these changes.