Firmware compatibility on near-identical devices or future-proofing

[frollic]

@Omnus

As such, I am thinking getting a pre-built router could be a worse choice as its hardware would not be upgradeable to better/faster ethernet/WiFi/etc. WiFi G > N > AC> AX >?

you could separate the routing from the WIFI, access points tend to last longer than routers, since there's usually no need for additional flash space on the APs, while a wired only router often have better routing performance.

@Omnus

I know I can install an x4 or x8 PCIe card in an x16 slot, but motherboards tend to have merely 1 or 2 of them with multiple x1 slots.

buy a better/bigger motherboard.

@Omnus

Or finding a WiFi card which can be run as master? Only found a vague reference somewhere to that being needed.

you can find threads about those cards in this subforum

@Omnus

Or the possibility of using a RaspberryPi or similar, but they seem too limited

they're actually pretty good, but mostly out of stock.

@Omnus

What I wonder from all that is how do firmware upgrades apply to such devices?

you upgrade it the same way as any router, or set up the new version in parallell to the
old one, and boot into the new version.

@Omnus

but what happens when OpenWRT firmware is updated?

you update it ?

@Omnus

Would OpenWRT firmware for a prebuilt router need to be manually rebuilt each update, or can it be updated easily?

all/most devices booting from build in flash have a sysupgrade images, which are used for updating from one version to another.

@Omnus

What if it was built on a PC or RaspberryPi?

then you dd the image to the storage, or use the built in update function.

@Omnus

What if the base kernel is updated?

you update the whole image.

@Omnus

is what is the effective lifespan of OpenWRT firmware for any type of device and how easily could upgrades be installed?

routers with fixed storage will be supported as long as the Linux kernel support the hardware, and there's flash space enough to accommodate the openwrt image, and RAM enough to run the content.

@Omnus

but would OpenWRT be indefinitely updateable on a PC?

Pretty much, yeah.
For a PC flash space isn't an issue, here it's the CPU that could eventually become a bottle neck, and not provide CPU power enough to route your internet traffic.

Here's a very future proof (wired) router, based on a DIY solution This topic is now deleted - #16 by frollic

If you want something cheaper read the beginning of Tips for getting cheap used x86-based firewall with full Gbit NAT (a PC Engines APU) if you are in the US then go to the 2nd half of the thread.