Update firmware of Asus wireless router to the enhanced Asuswrt-Merlin version

Asuswrt-Merlin is a 3rd party enhanced version of Asuswrt, which is the official firmware in used by all recent Asus wireless routers. Asuswrt was originally forked out from the Tomato-RT/Tomato-USB firmware, which in turn developed base on the codes of Linux-based HyperWRT, a 3rd party enhanced firmware for Linksys routers.

Asuswrt-Merlin is mainly developed and maintained by Eric Sauvageau (a.k.a. RMerlin) based on the Asuswrt firmware developed and maintained by Asus technical team.

Asuswrt consists of open sourced GPL codes as well as closed source proprietary components. Asus releases the source codes of Asuswrt firmware in their website, with the closed source portion included as compiled binary codes. This GPL release includes everything needed to completely recompile a working firmware, with the exact same features as found in their firmware releases, making it possible to enhance it into Asuswrt-Merlin firmware.

The general goal of Asuswrt-Merlin project is to provide an alternative to the original firmware, and remain in sync with Asus's own development of each firmware release, so that new features and bugfixes development in original Asuswrt firmware can be trickled down into the subsequent Asuswrt-Merlin firmware.

Asuswrt-Merlin is intended to improve but not to replace the original Asuswrt firmware functionality. Its priorities are: Stability > Performance > Additional Features.

The website of Asuswrt-Merlin is https://asuswrt.lostrealm.ca, and you can click here to view the list of its enhancements made on top of the original Asuswrt firmware.

There is an Asuswrt-Merlin forum in the SNBForums for community discussion and support of this firmware, and RMerlin himself is an active participant and moderator there.

To date, Asuswrt-Merlin is made available and supported for the following Asus wireless routers:

• RT-AC66U_B1
• RT-AC68U, RT-AC68P, RT-AC68UF, RT-AC1900, RT-AC1900P
• RT-AC86U, RT-AC2900
• RT-AC87U
• RT-AC88U
• RT-AC3100
• RT-AC3200
• RT-AC5300

You can check for new release of Asuswrt-Merlin firmware at the following places:

• If your router is already installed with Asuswrt-Merlin firmware, you can check for new firmware version by clicking the Check button in Administration > Firmware Upgrade > Firmware Version in the firmware's web GUI.

• By manually checking at the Current Release information at the Asuswrt-Merlin website.

• By manually searching for new topic in Asuswrt-Merlin forum with title "[Release] Asus-Merlin 384.x is now available".

You can click here to go to the download webpage of Asuswrt-Merlin firmware in its website, or click here to go to its main download site at SourceForge.

At the SourceForge download site, select your Asus router model correctly, then select Release, and download the latest version of firmware accordingly. The firmware is packaged in a ZIP file.

After the download, you need to unzip the file. Before uploading the firmware file to your Asus router, it is advisable for you to check for its SHA256 signature and match it with the checksum information inside the sha256sum.sha256 file. This is to make sure you won't upload a corrupted file to your router and potentially brick the router.

The easiest way to perform a file checksum in Windows is by using 7-Zip. Once you have installed 7-Zip in your Windows computer, you can right click on the file, select "CRC SHA" and then select "SHA-256" to get the SHA256 signature of the file.

If you want to install Asuswrt-Merlin firmware into a new router, make sure you have gone through the Quick Internet Setup wizard to get the initial configuration of the original firmware. You don't need to do this if you are installing to router already in used, be it currently running on original Asuswrt firmware or Asuswrt-Merlin firmware.

It is advisable for you to manually record down your major settings by using printscreen, and also make a backup of your existing settings by going to Administration > Restore/Save/Upload Settings. Save both your Router Settings and JFFS Partition (the later might not be applicable to stock firmware) to your local computer.

Then, you can proceed to go to Firmware Upgrade section, click on Choose File, select the Asuswrt-Merlin firmware file which you have downloaded, and Upload it to your router. The firmware updating process will begin, and your router will be rebooted.

Normally, your router will be up-and-running with no lost of previous settings after the firmware update. If you find it not working properly, you can try to Initialize your router to Factory Default, take out your printed screens and redo all your settings from scratch. If you still facing any problem, you can go to SNBForums and seek for help there.

Heat dissipating solution for Asus RT-AC86U router with USB cooling fans

The Asus RT-AC86U wireless router has a stand-up design and its heat management is relying on passive cooling.

Unlike those flatbed routers which we can easily provide heat dissipating solution to them by using normal laptop USB cooling fans, the temperature management solution for this stand-up router needs some tweaking to attach external fans to it. Luckily, there is ready made solution in the market, and it is quite cheap too.

If you are using AsusWRT-Merlin firmware in the router, you are able to read the runtime temperature reported at its Broadcom BCM4709 processor (CPU), Broadcom BCM4365E 2.4GHz WiFi SoC chipset and Broadcom BCM4366E 5GHz WiFi SoC chipset respectively.

In normal operation, the temperature at 2.4GHz WiFi chipset stays around 50-55 degree Celsius and the temperature at 5GHz WiFi chipset stays around 55-60 degree Celsius. However, the dual-core CPU temperature is always on the high side, staying above 70 degree Celsius, and there are users reporting that it can go up to above 90 degree Celsius.

If you are feeling uncomfortable with these kind of temperature readings and would like to lower them down to a more comfortable level, you just need to install a pair of external USB cooling fans at the back of the router.

The two 7cm fans are powered by 5V DC from the USB 2.0 port of the router itself. You can also plug it to the router's USB 3.0 port, but that port is normally used by external storage, USB Internet dongle, etc.

It is attached to the back of the router using 3M double-sided tape provided in the cooling fans set package.

Within 20 minutes, the pair of fans are able to cool down about 5 degree Celsius to both the 2.4GHz and 5GHz chipsets respectively. They can effectively cool down the temperature of the CPU by a whopping 20 degree Celsius.

With this heat dissipating solution, now the temperature at the 2.4GHz chipset reduced to around 45 degree Celsius, and the temperature at the 5GHz chipset reduced to around 52 degree Celsius. The CPU temperature greatly reduced to around 53 degree Celsius.

If I power down the fans by unplugging it from the router's USB port, all the 3 temperature readings will gradually increase, and went back to the previous high level within 20 minutes.

The fans are rotating at relatively low speed at 2100 RPM, making them pretty quiet. You can hardly hear their noise unless putting your ear very close to them during silent night.

According to their specifications, their noise level is at 18 dBA only. Their lifespan is around 50,000 hours, which is equivalent to over 2000 days, long enough to serve for the entire lifespan of the router.

Other than Asus RT-AC86U, this pair of USB cooling fans can also be used for Asus RT-AC68U router as both of them are having very identical size and casing build.

My Asus RT-AC86U AC2900 wireless dual-band MU-MIMO gigabit router with TM UniFi and Maxis Home Fibre support

The Asus RT-AC86U is a multimedia wireless router with gaming support, which you can also classify it as an entry level gaming router. For more powerful gaming router that gives you great online gaming experience, you should look for the ROG series instead.

It is the successor of the popular Asus RT-AC68U router, with similar stand-up design, identical front LED panel, rear connectors and buttons, but the internal circuit board is totally different. Thanks to this stand-up design, it has a much smaller footprint compared with those flatbed routers.

The CPU of this Asus RT-AC86U is powered by a dual-core Broadcom BCM4906 64-bit processor clocked at 1.8GHz (ARM v8 Cortex A53 architecture built with 28nm technology), which is apparently more powerful than the Broadcom BCM4709 processor used in Asus RT-AC88U AC3100 wireless router.

More powerful CPU provides better user experience for the more CPU intensive tasks, such as when using USB 3.0, SMB v2, data encryption, etc.

This Asus RT-AC86U is an AC2900 wireless dual-band MU-MIMO gigabit router. Oddly, it has lesser number of antennas compared with most of its counterparts in the market. It has 3 dual-band external antennas and 1 more internal antenna for the 5GHz radio band. Well, do not be fooled by this appearance. Indeed, its wireless signal strength and reach is pretty powerful.

Powered by Broadcam's NitroQAM support with 1024-state quadrature amplitude modulation (1024-QAM), if the connecting wireless device is also supporting 1024-QAM, each data stream of its 2.4GHz band can have a maximum data transfer rate of 250Mbps, and each data stream of its 5GHz band can have a maximum data transfer rate of 541Mbps. Both are 25% higher than the older TurboQAM technology (each 2.4GHz band = 200Mbps, each 5GHz band = 433Mbps) in used by predeccessing wireless routers such as Asus RT-AC68U.

Its 2.4GHz radio band is powered by a Broadcom BCM4365E 3×3:3 SoC chipset, able to serve a combined maximum data transfer rate of 3 streams of 250Mbps = 750Mbps.

Its 5GHz radio band is powered by a Broadcom BCM4366E 4×4:4 SoC chipset, able to serve a combined maximum data transfer rate of 4 streams of 541Mbps = 2,164Mbps.

However, most of the mobile devices nowadays are still using the 256-QAM technology, which supports maximum data transfer rate of 600Mbps in 2.4GHz and 1,733Mbps in 5GHz. Only the latest mobile devices with 1024-QAM support are able to unleash its full potential of serving 750Mbps in 2.4GHz and 2,164 in 5GHz.

The 2.4GHz wireless network of this router just performs a decent job, on par with other good quality wireless routers. Its main strength is on the 5GHz wireless network, which surprisingly having a very strong, far and stable reach. It is still detectable and accessible in locations which are beyond the reach of the 5GHz wireless network of my previous router.

With this Asus RT-AC86U router serving from the middle of my house, I don't even need to use any range extender to have stable and fast WiFi in every corner of my house. The WiFi signal, powered by Asus Range Boost technology and AiRadar beamforming, can also be detected further away from outside the house.

This Asus RT-AC86U has a total flash memory of 256 MB, and RAM of 512 MB. Both are doubled when compared with Asus RT-AC68U. It is pretty feature rich, configurable through Asus' famous AsusWRT web interface.

It has dual WAN support, which the second WAN link can be supplied using a 4G USB dongle or USB modem, or making use of one of its gigabit LAN ports for WAN purpose. The secondary WAN link can be configured for load-balancing or standby as failover backup link.

It supports TM UniFi IPTV by simple setting and connecting its LAN Port #4 to the TM UniFi set-top-box. It also supports IPv6 flawlessly.

It supports up to 3 separate Guest Networks in the 2.4GHz band, and up to another 3 separate Guest Networks in the 5GHz band.

Being a multimedia wireless router, it has features such as AiCloud 2.0 which enables the router to provide file server function and even media server function by attaching USB storage device such as USB thumb drive or USB external harddisk to its USB 3.0 port.

You can configure for the file server function and/or media server function to be accessible from local network only, or even from the Internet. Having dynamic WAN IP is not a problem, as you can configure the router to make use of DDNS service, so that you can always connect back to your router with its DDNS domain name.

By making use of Samba service, it can also provide Smart Access function for you to remotely access through Internet to the shared files and resources in your local network.

Access to AiCloud 2.0 can be made via its web interface, or by using the free AiCloud Android or iOS mobile app.

Its USB 3.0 file sharing is pretty fast. Accessed from LAN, my Transcend StoreJet 5400 rpm 1TB portable hard disk with NTFS partition attached to the router is accessible with a read speed of 101 MB/s (808 Mbps) and a write speed of 89.9 MB/s (719.2 Mbps).

It provides AiProtection feature with Trend Micro, with malicious sites blocking, 2-way IPS and infected device prevention & blocking. This is able to give you an additional layer of protection at the network perimeter, on top of the antivirus/anti-malware protection that you installed in your computers. You would not be surprised to see AiProtection successfully intercepted some malicious website accesses that skipped through your computer's antivirus/anti-malware screening.

It also equipped with Parental Controls function that enable you to block access to websites of certain criteria (such as adult websites). In addition, you can set time scheduling for the computers and network devices in your network so that they are restricted to access the Internet during certain time period.

Parental Controls works best together with the free Asus Router mobile app available for Android and iOS. In the mobile app, you can define which network devices are used by which family member, and the mobile app will block the adult websites for your children under 18 years old.

Its Adaptive QoS function enables you to set priority for certain network traffic, useful for online gaming. You can also configure it to make use of WTFast Gamers Private Network for faster online gaming experience.

This Asus RT-AC86U has quite frequent firmware updates, particularly to patch up security issues or to fix performance issues. Other than using the stock firmware, you also have option to install customized firmware such as the AsusWRT-Merlin firmware which is developed based on the stock firmware and more emphasis on security, usability and stability.