@j3tz, I wouldn't be relying on an old Linux book to help too much with Asus routers today. Although, I'm sure for many it would be useful/interesting to have such in-depth knowledge of what is going on under the hood. It is simply not needed. I have no such knowledge, nor care to learn it at my age.
From what I understand and what has been explained (by RMerlin) here, the underpowered hardware we are running today isn't capable of running a full Linux install. That is why knowing/learning about how Linux works doesn't help too much with today's consumer routers (and specifically, Asus/RMerlin firmware).
What I suggest for a stable, dependable, and performant network is to install the firmware you want to use (and with your knowledge and curiosity, RMerlin firmware is the better fit than stock Asus), then perform a full reset to factory defaults using the appropriate method for your router in the link below.
What I also (always) do for customer setups is an additional full reset to factory defaults via the GUI while also making sure to check the box to 'Initialize all settings...' too, before hitting the Restore button to initiate that full reset.
To be sure, I do those two resets at least twice each. While also re-installing the same firmware the router already has installed (and I want to use it with).
Overkill? Maybe. But I'd rather spend 15 minutes extra before I start configuring the network than spend an hour or more afterward (or worse, being called back by the customer because the network isn't stable).
I update, fully reset, and (almost fully) configure every single router before it ever gets the WAN port connected to the outside world.
With new SSIDs, passwords, and usernames, I am now a bit more confident that the router/network is controlled by me (and that control will eventually be passed onto the customer, and often with a new password and username that only they know.
Before enabling any type of AiMesh setup (wired or wireless), I make sure that the main router and network are operating at their full capacity, are dependable and reliable, and there are no glitches or indications that may indicate incompatibilities between client devices or possible hardware issues either.
Only at this point do I consider adding an AiMesh node, after having rebooted the main router one last time and waiting at least 10 to 15 minutes for it to settle down (just the right amount of time needed to unbox the node, flash the firmware you want to use on it (recommended: use the same firmware as the main router for maximum stability and reliability of the network), and perform the full resets as described for the main router above. After the last reset on the node, do not access its GUI. Instead, add it to the network via the main router's GUI (add AiMesh node).
The following link has more detailed info on the few paragraphs above.
I have an ASUS AX86U and contemplating the installation of Merlin firmware. The DDNS settings on the AX86U are limited to select dns providers. If I install Merlin, will I have more flexability (choices) with the DDNS Settings? Thanks in advance!
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More information can be found in the links below.
After creating the checklists two weeks ago to save the pages with settings, I've made all the screenshots (I think at least) of all the relevant guides written by @L&LD and the very useful tip by @netware5. The only thing is, those guides are great, except when you'll be offline at least for a...
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Top 10 Simple Asus/RMerlin firmware powered Router Troubleshooting steps to try first: NOTE: Although this is for Asus/RMerlin-firmware powered routers, the steps below may be relevant to all routers, to get to a quick fix for common symptoms. Check that the router’s System Time is accurate on...
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And, when you have new firmware available, you may want to do the following before you proceed with the upgrade.
I have had issues in the past when updating firmware and Internet speed, But it may have just been a fluke, Should I keep up with the updates? If so On all routers or the nodes as well? What about ones acting as access points? Thanks
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Which will allow you to quickly get back to your current working setup with minimal fuss.
And, maybe more importantly, if the new firmware seems to introduce issues, you can perform a full reset of the router with the confidence of knowing you can quickly get back to a working network very quickly, and fully/properly test if the new firmware has a bug or if it was just unexpected interference with the previous firmware's variables, defaults, and other settings/interactions that may have been changed from old to new.