Posted: Mon Nov 26, 2018 15:13 Post subject: [Asus RT-N18U] Problems with Guest Network after Reboot
I've recently bought this router (Asus RT-N18U) and have been since configuring it with DD-WRT.
However, I’ve stumbled upon an issue I can't seem to quite solve:
After configuring the Guest Network following the DD WRT Guide, the Wireless Network will work properly as expected. However, if i reboot the router, no device can connect to the network. As far as i can tell, the router can't even provide an IP address to the device.
Here's the weird part: If I change any option in the wireless settings (For example: The name of the network, AP Isolation, etc.) and apply, the network immediately starts working just fine.
- Configured the DHCP-Server using DNSMasq instead of the GUI option;
- Configured the NAT and NET INSULATION rules directly on the Firewall Startup commands;
- Disabled the AP Insulation.
None of these tests worked, after rebooting the router the guest network will simply not work. The only situation where it worked was keeping it bridged with the internal LAN network, this way it worked after reboot.
I did not find out why this happens, however I did find a workaround to make sure it works after booting.
Turns out, after further testing, that it's not needed to change any settings at all in the Web Interface: All you need to do is press "Apply Settings" and the router will automagicly restart something in the services and the Guest Network will start working normally until next reboot.
I tried to simulate the "Apply Settings" in various ways, but none worked.
Just to help someone with the same problem go faster, here's the commands i tried running using telnet / run commands (These did nothing):
# Try 1:
- wl radio off
- wl radio on
# Try 2:
- wl down
- wl up
# Try 3:
- wl -i wl0 down
- sleep 3
- wl -i wl0 up
Since i could not figure out what commands the "Apply Settings" button runs, i figured: why not make the router press the button itself?
To archive this, i used curl, and Google Chrome to obtain the CURL URL. Here's the Step-by-Step i did to get the router to "press" the "Apply Settings" button automatically. It will "press" it 20 seconds after startup (so it waits a little while for everything to load up before "pressing" it):
1 - Open the Router Page, go to Wireless Settings;
2 - On Google Chrome, Enable "Developer Tools";
3 - Still on Chrome, go to the "Network" tab under the Developer Tools;
4 - Click on the option "Preserve Log";
5 - Press the Apply Button:
6 - Wait for the router to apply the settings.
7 - On the list, you should see various elements being loaded. Find the element called "apply.cgi"
8 - Rightclick "apply.cgi" and select "Copy" and then "Copy as cURL (BASH)".
On Notepad, paste the URL you just copied. You can clean it up a little bit before using it if you want. I cleaned mine like this:
Just an update on this issue: The issue is still present, however in the latest build (r39267) my fix no longer works.
In my case, even the fix jwh7 presented also didn't work, but I'm not sure if it is the same issue or not (i say this because in this latest build, after hitting apply or applying the fix bmentioned before, the wireless networks just disappear from all devices (all except the main one).
This was tested using 3 Wireless Networks (1 Internal, 1 Guest, 1 Separate for testing).
Latest builds do seem a lot unstable for my setups. For this particular router, i ended up with the build r34411 for now, as everything seems to work mostly smoothly!
This setup i'm referring to is one of many i use. This specific one involves having 2 separate LAN networks, as well as 3 different AP networks.
Basically, LAN 1 and LAN 2 are to separate two working environments. The third connecting (Guest AP) is configured just like that: AP Isolation, NET Insulation, and a few more rules to prevent it from using other DNS servers than the specified ones, as well as prevent it from accessing the WAN subnet.
I also have several other setups with different requirements, for example:
1 of the setups (at home) runs some 15 Atheros based ones WR841N in a somewhat huge LAN i've built at home along with the neighbors
Other one is using two ASUS RT-N18U to provide a VPN tunnel between two points.
I have submitted a "status report" in the changelog thread. Here's hoping i can help sort the issue out on this router