Hacker News Reader

Comment by silicon2401 | Hacker News Reader

As a pi noob: does this make it more reliable/feasible to use a pi to run a home server/application/etc? I've read in the past that SD cards aren't good with repeated read/writes, which makes it somewhat unreliable in the long run. If a pi is configured to run via USB, does that make it as reliable as other consumer hardware like a pc/laptop?

View on HN

Other commenters in this thread have mentioned netbooting their Pis to avoid that exact issue. A typical USB flash device won't be any more reliable than an SD card, though it might be better cooled.

> A typical USB flash device won't be any more reliable than an SD card, though it might be better cooled.

That’s not strictly true, as the USB storage controller abstracts away the NAND and can manage wear leveling and free blocks. There are also more “enterprise class” USB sticks than SD cards, and the USB3 interface to USB drives is much faster than pretty much any SD card interface.

Best SD cards and best USB drives are Sandisk Extreme Pro, built entirely differently from their other lines. While Samsung Evo SSDs are top-of-the-line in each budget class, stay far away from their Evo SD cards which shamelessly borrow off the SSD reputation then drive it to the ground. They all tend to go read-only after undergoing “extended” writes.

Suggestion: if you’re using Linux, stay away from the ext family of file systems when using SD cards. Use nilfs or f2fs, and XFS if you absolutely must use a journaled fs.

Can confirm the read only. Indeed had it with 2 cards now. It's really annoying because the OS still caches writes in RAM so you only find out when you reboot and all your changes are lost.

Still, not quite as bad as completely corrupting I suppose...

Several manufacturers offer endurance-oriented microSD cards. They're designed to store footage from security cameras and the like, so they should have the write endurance to handle most any workload you throw at them. Depending on the write endurance you desire, they range from only a few bucks more than a regular microSD card to roughly double the cost.

You could always use a real drive for storage on some mount point, or even as an overlay on a read-only SD card. Being able now to boot directly off a SSD is more convenient, though.

My router / firewall is an RPi3 booting from a USB drive. A regular SD card would wear off after a few months, but a USB drive will last a long time.

Reply on news.ycombinator.com