"mesh" is a buzzword that doesn't make much sense (to me at least) if we are talking about wired and routers... what do you mean by it? can you describe your setup?
edit:
Let me clarify :)
Unless I'm mistaken, mesh means that one a bunch of devices, usually wireless access points, connected with each other (in a mesh) with possibly low-quality connections that automatically switch traffic for each other.
If you have ethernet running from the router to the APs, you always want to use that and so you don't want a mesh at all.
Yeah mesh to me means you talk to one AP wirelessly and that AP talks to another AP also wirelessly to eventually get to a wired connection to the internet. Of course that can also be wireless (SpaceLink, Verizon, etc) but out to the internet. I much prefer each AP has its own ethernet backhaul because both latency and throughput are significantly better. Of course it’s not as convenient since you have to have wired connections at each AP location.
Mesh in this case means one wifi network visible to wireless devices with multiple nodes broadcasting it. In my case both nodes are connected via ethernet.
Yeah, this is how I understand it too. From the end user's point of view, there's just one wifi network throughout the building or property. It doesn't matter if there's a cable running between the access points, that's all invisible to the user.
It’s probably not relevant to the question in the OP, but a mesh between routers makes sense in a dynamic routing scenario. If you have a mesh of routers running iBGP for example, you will always have a path to other routers in the network even if you lose one and the routing protocol will select the best path to the destination network based on what’s available.
Also, if we’re talking about devices on the same broadcast domain (like multiple APs serving one SSID), you don’t need a router to forward that traffic. Everyone on the same layer 2 segment can ARP for each other, so it’s not a bad idea to just let your L3 devices L3 and let your L2 devices L2. If there is an issue with connection quality, solve that :)
I'll just quote the OpenWRT Wiki here, because I think half the comments here confuse mesh and roaming:
Are you sure you want a mesh?
If you are looking for a solution to enable your user devices to seamlessly roam from one access point to another in your home, you need 802.11r (roaming), not 802.11s.
It is unfortunate that some manufacturers have used the word “Mesh” for marketing purposes to describe their non-standard, closed source, proprietary “roaming” functionality and this causes great confusion to many people when they enter the world of international standards and open source firmware for their network infrastructure.
The accepted standard for mesh networks is ieee802.11s.
The accepted standard for fast roaming of user devices is ieee802.11r.
Which standard should I be looking into if I want a second AP/device that connects to the “main” router wirelessly, that extends the network range. I live in an apartment and can’t run Ethernet.
Well, I'm cheap so instead of spending 300 bucks on a Google router I bought three Xiaomi ax3000T for €35 a piece. They are listed as compatible with openwrt but for the last couple of month I've just been using them with the stock firmware and the WiFi mesh with backhaul works great.
It's otherwise very basic though, it lacks many features you'd expect like guest AP and so on..
I apologize. I misunderstood that you were looking for a mesh system that would work with an existing openwrt router. Seems what you're looking for is a mesh system that can be flashed with openwrt.
For that I can only suggest that you look at the supported hardware table and see if you can find what you need.
I was able to get some Linksys E8450 routers for cheap (~$40 each) on eBay a couple years ago, but they are more expensive atm (but $70 each, which is cheaper than a lot of other options). They require a bit of work to get OpenWRT installed, but it's not bad once the work is done (I have received nearly 400 Mb/s when I am close to the wireless connection sometimes, which is what my internet is capped at). I have used them as a mesh with one as a main gateway and the rest as access points with additional Ethernet ports. They do have the OKD issue fixed now, too, and they're also Wi-Fi 6. I'm looking into getting a Banana Pi BPI-R3 or R4, though I am not sure how well they are with mesh specifically, but have seen a few forum threads of people having some issues with mesh on these specific routers. I hope to switch to fast roaming (wired backhaul) eventually.
What you're after, transparent wifi roaming, is actually mostly handled by the client; what you need is wifi access points that don't get in the way.
I don't have much experience with new OpenWRT supporting products, but the kicker is you only need one of them. If you have multiple routers, they will require some setup to play nice with each other. An "Access point" is just the wifi provider, can be hooked up to provide whatever the one router manages, and are generally cheaper than a router.
To that end, I'd suggest a single router, and multiple access points. I do this with Ubiquiti access points in my home, their PoE has been nice and they have been pretty "setup once and forget" for a few years now. I'm sure there are some other brands that'll do well; Ruckus and Mikrotik come to mind.
I just started migrating my network from PFSense, a bunch of tplink switches and Aruba InstantOn APs to unifi. I'm almost done (just missing a couple of APs more and 1 more switch), and I honestly am extremely happy with the decision. The Unifi APs are not as powerful as the Arubas, but the improvements to the performance of my network more than makes up for that.
There are two models I've used for this over the years, the Linksys EA8300 and the WRT 1900AC. Here's how I did it both times (though I only got around to writing up my notes the second time.
Just purchased the Orbi setup and the performance improvement over my gen one Google mesh was shocking. I expected an improvement but my Xbox went from ~40 mbs to 240 mbs for straight game download. I did keep my old Google mesh up and running also and only use it for phones/tablets.
Yeah they were pricey, I should have mentioned that. I did not attempt that install. Wanted to just get it up and running first without any of my usual shenanigans.