It has been a while since my WiFi is getting more and more unstable, and I finally decided to retire my NETGEAR R6300v2 which has served me well since in 2017.

It was in used condition when I bought it, so this is a good time to get a “new” router.

Because the ISPs in my area are very bad, I still have to stick with the low speed Internet for probably quite some time. So I decided to buy a used Linksys MR7350.

This model is very cost effective (less than $30 with adapter & cable), and will not bottlenecking my Internet whatsoever. More importantly, it is supported by custom firmware builds like OpenWrt and DD-WRT, although the support is not yet stable.

Right now, the official full support from OpenWrt is still in development, and people are actively testing the current SNAPSHOT build.

I would like to join their testing when I have more free time, but for now I’m flashing DD-WRT instead since it has a stable build and more detailed wiki guide.

I have tested the latest r62324 build, which crashes every time while entering Wireless page.

Installation

According to pepermint in this thread, the last working version is r61848, so this is what I need.

Unfortunately DD-WRT website does not provide checksum information. So I have to do this roughly by looking at the file size. But I would like to share my hash for the record:

dd-wrt-webflash.bin
69 MiB
SHA256:785E8A43103BA0D24E63C7750A97F5C7D7C3306792084144BEFA6C736C67B841

factory-to-ddwrt.img
34 MiB
SHA256:D5C3BB7EC0F6A3D5F55D93AAF1A9273895067AFB31AD4429DD43EE009326AD2A

As I mentioned before, for better operational security, I flash firmware and configure initial setup without WAN/Internet connection.

The installation guide is very detailed, I don’t need to add to that.

After the connection between router and computer is backing up and getting a new IP address, continue the process via 192.168.1.1

Configuration

Make a strong password for the sake of security by following Snowden’s rule, then proceed with the upgrading section of the guide.

The flashing the firmware will be finished very quickly because of the CPU speed, next thing to do is goto Setup page and enable WAN connection by selecting Automatic Configuration - DHCP

Select NSS-ECM for Shortcut Forwarding Engine to optimize the overall performance, and leave everything else default if change is not needed

In the Network Setup section, fill out desired Local IP Address for this router and Gateway for anything it connects to

Go to the Wireless Basic page for WLAN interface setup, set Mode as AX/AC/N Mixed , Channel Width as Dynamic (20/40 MHz) and Channel 36-165 for 5GHz, too high can result compatability issue (refer to Status - Wireless - Channel Survey to find a high quality channel). For 2.4GHz WLAN, using N/G Mixed mode and Dynamic Channel Width is a good balance

On the Wireless Security page, set WPA3 SAE and WPA2 with CCMP-128 (AES) as Authentication method, extra security options such as Disable EAPOL Key Retries for KRACK mitigation are not needed since they are already patched up by default

Add Virtual Interfaces if a guest network is needed

In the Serivce page, disable anything that is not needed, such as SSH/Telnet/WPS…

Enable USB support if there is a printer or USB drive to be used and Enable all Block WAN requests and Impede WAN DoS options if this router faces Internet directly

After all done, it’s time to connect the Internet cable into the WAN port, and change the settings in Setup - Advanced Routing - Operating Mode if there is no Internet

Run a speedtest and watch the temperatures under Status - Router - Sensors, under 60C should be fine and there should be no bottleneck for the speed as well

I’ll update this post if it runs unstable, otherwise, cheers!