Migrating from RT-AC86U to RT-BE86U need advice

[Chris12]

Hi,

I'm currently using a RT-AC86U a my main router. Recently I bought a brand new RT-BE86U router, which will be replacing the old AC86U.
The AC86U is running the latest Merlin version available for that model, and I have flashed the new BE86U with Merlin version RT-BE86U_3006_102.4_0 (and after that did a factory reset via the GUI, which should be sufficient to remove any old Asus firmware/config isn't it?).

How can I easily setup the new router with the same kind of config as the AC86U has?
Is the best way to go configuring the BE86U completely from scratch? Or import the config backup file from the AC86U into the BE86U (and then check the settings).

I want to replace as much as 1:1 the old AC86U with the new BE86U, so same WiFi names etc. so the impact for other devices connected later on to the new router are minimal.
Or is this not a very good way to go, as the new router has far more options (like separate IOT wifi, Guest networks etc.) which I currently not use, but maybe worth to setup/investigate using?

My plan for now is:
- setup wifi networks with a -NEW prefix on the BE86U, so both routers can work besides each other.
- configure the new BE86U router with the same settings as the old AC86U router
- replace the AC86U router with the new BE86U router
- rename the wifi-networks (remove the -NEW prefix)

 

[Tech9]

Is the best way to go configuring the BE86U completely from scratch?

Yes. The only way.

Or import the config backup file from the AC86U into the BE86U (and then check the settings).

No. Not compatible.

 

[bbunge]

You may be better off with an AX86U Pro. Many still consider WIFI 7 in beta.

If you do not need WIFI 7, don't!

 

[Tech9]

I would also prefer RT-AX86U Pro unless 2.5GbE LAN ports as switch are important. Both have about the same wireless performance and not true 2.5Gbps capable hardware inside anyway. The AX-class model is cheaper and has 3004 firmware choice in case something doesn’t work as expected in 3006.

 

[Chris12]

Thanks for all the replies.

I managed to configure the router so all things works again (VPN/Airco Units/Domoticz/IPCams/etc.), except my Hosola solar converter who not seems to like neither wifi network and/or wifi settings.
But I will dive deeper into that problem tomorrow or later this week.

Let first see how the router is acting the upcoming days/week.

 

[Chris12]

Thanks for all the replies.

I managed to configure the router so all things works again (VPN/Airco Units/Domoticz/IPCams/etc.), except my Hosola solar converter who not seems to like neither wifi network and/or wifi settings.
But I will dive deeper into that problem tomorrow or later this week.

Let first see how the router is acting the upcoming days/week.

For the Hosola wifi to work, I just had to reset the wifi config, and re-add it again with the new wifi ssid. instead of editing the existing wifi settings.

 

[RocketJSquirrel]

I'm about to perform this upgrade as well. AC68U to AX86U Pro.

Can I install Merlin firmware on the new router before doing any configuring? Or should I perform initial configuration using the stock Asus firmware and install Merlin after initial configuration is complete?

 

[jksmurf]

I'm about to perform this upgrade as well. AC68U to AX86U Pro.

Can I install Merlin firmware on the new router before doing any configuring? Or should I perform initial configuration using the stock Asus firmware and install Merlin after initial configuration is complete?

Unless it’s very old FW (*j on the new router which is highly unlikely you should be able to go from basic stock to Merlin straight away, do a WDS hard reset and then put all the configuration settings in by hand from the screencaps you made of your old router settings. You did save the old settings as screencaps right?

On basic stock you will need to go through a few screens setting up a Wi-Fi, admin login details, so you can get to the Webgui to be able to upload Merlin; and do all that a second time after the hard reset to start inputting your settings.

If you have lots of dhcp assignments saved, save a copy of dhcp_staticlist and custom_clientlist too. You can drag and drop those back after installing Merlin.

[EDIT] * wrt very old, the Asus FW download websites for the RT-AX86U Pro model show only 3006 (3006.102j codebase FW dating back to 2024. However I believe the much older FW on those models was 3004 (3004.388) codebase FW. In this case it might be prudent to flash stock to latest 3006, hard reset, then Merlin 3006 and hard reset.

 

[RocketJSquirrel]

[EDIT] * wrt very old, the Asus FW download websites for the RT-AX86U Pro model show only 3006 (3006.102j codebase FW dating back to 2024. However I believe the much older FW on those models was 3004 (3004.388) codebase FW. In this case it might be prudent to flash stock to latest 3006, hard reset, then Merlin 3006 and hard reset.

Thanks for the info. I appreciate the response.

I am seeing ASUS RT-AX86U Pro Firmware version 3.0.0.6.102_34406 dated 2025/10/28 on the Asus download site. That looks recent enough for me.

 

[ppfoong]

You can have both the old and new router running side-by-side, just make sure their IP address is different.

Then, you can either use a big/long monitor to open both config webpage side-by-side, or use dual monitor, or use different computer/laptop/tab to open each. In this way, you can manually copy over the settings from the old router to the new one.

For WiFi settings, you might want to configure from scratch for the new router, as the WiFi capability and best options on/off config will not be the same. This is because if you use the old conservative WiFi settings in the old router for your new router, you are not getting the best from the WiFi capability of your new router.

 

[RocketJSquirrel]

You can have both the old and new router running side-by-side, just make sure their IP address is different.

Then, you can either use a big/long monitor to open both config webpage side-by-side, or use dual monitor, or use different computer/laptop/tab to open each. In this way, you can manually copy over the settings from the old router to the new one.

That is an interesting idea! Have you (or anyone else) used this technique successfully?

 

[lgkahn]

That is an interesting idea! Have you (or anyone else) used this technique successfully?

yes i do that all the time to config a new router.. i put it on a different ip with a direct plug from my laptop and then goto the old one via wifi and copy stuff. the only complication is if you want it on the same ip as the old you can switch after its all set up , also recommend if using wifi you disable the bands in professional after each is set up so as not to conflict with one you are copying.

and the big issue is you cannot setup the dhcp leases if the ip is on a different subnet , just leave default gateway blank on your net adapte ron the pc while setting up.. then move it in place after unplugging the one you are replacing.

i setup the dhcp leases anway manually by putting the lease file in jffs

 

[bennor]

That is an interesting idea! Have you (or anyone else) used this technique successfully?

Yes people run both side by side on a display to copy values from one browser window router GUI to another. Its what I've done in the past when replacing a RT-AC68U with an RT-AX86U Pro and have done it often with other devices.

 

[RocketJSquirrel]

I am trying this now (side-by-side router displays) and failing. My laptop is directly wired to the new router but cannot connect to it. www.asusrouter.com doesn't work. I don't know what I'm doing wrong. Any ideas?

 

[bennor]

I am trying this now (side-by-side router displays) and failing. My laptop is directly wired to the new router but cannot connect to it. www.asusrouter.com doesn't work. I don't know what I'm doing wrong. Any ideas?

Depending on how you have things configured you may need to reconfigure the laptop's Ethernet port for a fixed IP address in the same subnet range as the router it's connected to.

 

[lgkahn]

use the ip not the url.. if you havent changed anything and its new you should have set the ip to static in the 192.168.50.x network and the router should be 50.1

 

[ppfoong]

I am trying this now (side-by-side router displays) and failing. My laptop is directly wired to the new router but cannot connect to it. www.asusrouter.com doesn't work. I don't know what I'm doing wrong. Any ideas?

Initially, you need to connect directly to the new router using DHCP. The default IP address of the router is documented in the manual, and you can try 192.168.50.1. At this stage, your laptop need not connect to your local network or Internet, just connect it to the new router directly.

Once you have access to the new router, you can update its firmware (stock latest, or Merlin latest). Of course, the new firmware file need to be downloaded in your laptop before this.

After the firmware is updated, you can set the new router's IP and subnet mask in the LAN setting for it to join your local network.

Then, your laptop can join back to your local network as usual, and you should now have access to your new router with its new IP as well, under the same subnet IP range.

Then, you can configure your new router.

Then, unplug your old router from your network, swap it with your new router, set the IP address of your new router as your router's IP address, your devices should now connect to your new router and use it to access to Internet.

You can then reset your old router and make it as an Aimesh node, and move it to its new place. This can be done via WiFi, as long as you don't plug your old router to your network after the swap, you need not change its IP address even before reset. Alternatively, before you unplug your old router from your network, you can change its IP address first. This can avoid IP conflict when you have both your old router and new router connected at the same time. After you reset your old router, its IP will be reset too.

If you do not plan to make your old router an Aimesh node, you can skip the paragraph above. You can proceed to reset the old router, and your old settings will be gone. You can then store/relocate/resell/dispose it.

 

[RocketJSquirrel]

Thanks for the further info. Now I remember why I don't update router hardware very often. I wish there was a magic "copy all settings from router A to router B" technique.

My setup is a little strange, as I don't use router WiFi at all; both radios are turned off. I've been using 3 Orbi WiFi units with wired backhaul to cover my long ranch house. My original setup, with a single WiFi router in the middle of the house, didn't cover the territory.

 

[bennor]

I wish there was a magic "copy all settings from router A to router B" technique.

Because a router may have different features, options, or an entirely new GUI, copying all the settings as you suggest may not work or may introduce unexpected router behavior. Even using the router's inbuilt configuration file save/import option may cause unexpected behavior if that router.cfg file is imported into a different router model, different firmware version, or different router GUI.

Unless one has made many changes in the router GUI settings it actually doesn't take all that much time to manually enter the changes into a new router's GUI. There are various ways to copy over any manual IP reservations if one uses manual IP reservations.

PS: There are some addon scripts that may help with the move between routers.

YazDHCP - YazDHCP v1.2.4 [2025-Nov-21] - Feature expansion of DHCP assignments (increasing limit on the number of DHCP reservations)

Release Notes for YazDHCP v1.0.8 production version now available [2025-May-29] The fork from @Jack Yaz's repository is now hosted on the AMTM-OSR GitHub repo: https://github.com/AMTM-OSR/YazDHCP 1) FIXED: Errors when loading the webGUI page on the 3006.102.x F/W version. 2) FIXED: Some...

www.snbforums.com

BACKUPMON - BACKUPMON v1.9.1 -Oct 28, 2025- Backup/Restore your Router: JFFS + NVRAM + External USB Drive! CIFS/SMB/NFS! (Available in AMTM!)

BACKUPMON v1.9.1 Released October 28, 2025 First off -- HUGE thanks to @Jeffrey Young for sharing his original backup script. His script is the main engine of BACKUPMON, and all credit goes to him! BACKUPMON is simply a wrapper around Jeff's backup script functionality, adding easy-to-use...

www.snbforums.com

And possibly:

Script to Back Up & Restore Subsets of NVRAM Variable Settings.

I moved this thread's topic from this post as it was off-topic in that particular thread. NOTE: The script was moved to GitHub. UPDATE [2025-Sep-23]: The latest Release 0.7.18 version is now available. I've made a tweak in the code so that on a first run, it will try to find the input file...

www.snbforums.com

Same issues remain however if the new router has an entirely different firmware or set of options that were not present on the old router.