I have a solar powered Pi3B that has OS on SD-card, a normal quality Sandisk 32GB. It loses power every day at least once. No corruption, it always comes online, via proprietary 2.4GHz wireless link. Its function is basically a hub between RJ45 and USB (4T HDD), so a wireless NAS sort of.My main concern is how well the microsd can handle prolonged reads/writes and power failures (it doesn't happen regularly, 3-4 times a year, but if I'm away , it's a problem).
Fake or old bad brand SD-cards can indeed be a real PITA, but if you use a CoW filesystem for rootfs (Btrfs) you have a rather good method to filter those. Kingston for example is on my blacklist. Old Samsungs bought 10 years ago still work fine.
If you do have high demand on storage I/O and want/use and SSD, it can cause more trouble than you wish. Not the SSD itself, but the PCI-e to USB3 chip on the Pi4 board and also the USB3-SATA chip in some adapter cable. Also note that a Pi4 is not a CM4.
If you are concerned, use overlay filesystem. But as indicated, a wireguard 'hub' for a few mobile phones does not need a lot of storage I/O.
You mentioned 80Mbps, is that limit of Pi3 or mobile link or else?
A Pi4 has real GbE, not USB2 connected, so if you want highest speed, do not use a Pi3. I would actually get some SBC with on-board eMMC, there are several and also several with 2 RJ45, so you can also make it a full (cascaded) router with OpenWRT or so. But Raspberries have very good OS/SW support and are easy to get running, so a Pi4 with SD-card is fine.
Statistics: Posted by redvli — Sun Jul 06, 2025 8:40 am