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Comment by reitanqild | Hacker News Reader

Anyone has links to similar articles with regards to either

- SD card reliability

- techniques for reliably using what we have

Given that people are using these for all kinds of stuff there must be some advanced techniques being used (or some basic I have missed).

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I've been running a raspberry 3 with a cheap sandisk sd card for years now without any SD Card issues. It runs a DNS based ad-blocker and a vpn.

I am logging everything to ram instead of writing it to the card and that's about it. I never encountered any issue with SD Card reliability, despite me sometimes just pulling the plug instead of properly shutting it down.

Here is a simple guide: https://raspberrypi.stackexchange.com/a/62536

I do have a couple of other raspberries for other uses (e.g. a small rc car) which are also running on their first SD card. Might be just luck, but I do think that it's not necessary to go to extreme lengths to have them run reliably.

Many problems with SD cards are actually rooted in power issues (bad power source or usb device that eats power). Ever since I took proper measures to ensure stable enough power I've had no issue (Pi 3B here)

I can second this. My previous company runs a few hundred Pi units across loads of separate locations; the locations where we had constant corruption issues were also the ones experiencing dodgy site power-supply issues. We did try various alternatives to cheap SD cards but ultimately running them off PoE from a switch attached to a UPS was a pretty good solution to the issue.

Can you elaborate on these measures? Sounds interesting.

> Many problems with SD cards are actually rooted in power issues

Does anyone have any info on this that's more substantial than hearsay? Experiments, measurements or at least a more technical explanation than "bad power source"?

I'm persistently hearing this story that power supply quality affects SD card life. As an electrical engineer, and given what I know about R. Pi design, I fail to see how an SD card could get physically damaged by any reasonable power supply that would otherwise run the rest of the R.Pi.

I suspect people are confusing filesystem corruption due to brownouts/OS not shutting down cleanly with physical damage to the flash (i.e. unreadable sectors on SD card)

> I'm persistently hearing this story that power supply quality affects SD card life

Not SD card life indeed (in my case at least), merely IO failing, hosing the filesystem long term because of b0rked writes. The SD card is fine, it's just the data that eventually becomes inconsistent garbage.

I noticed the power LED showed the undervoltage behaviour, measured the power output which indeed showed the voltage not being stable on power spikes, so bought a better power supply, problem gone. Got the same kind of issue with greedy USB devices, so either went the powered hub route or used self-powered hard disks.

Regarding microSD card reliability, one option would be to simply forego the microSD card completely and boot the Raspberry Pi 4 via an SSD connected to one of the Raspberry Pi’s USB 3.0 ports.

I was originally going to recommend checking out this¹ article for instructions on how to do it. However, much of the instructions are no longer valid (as of two weeks ago!) since they assume that the Raspberry Pi 4 doesn’t natively support booting from USB, which finally isn’t the case (although only if you use the current beta bootloader²). I’d still recommend reading it though, as it also mentions known working 2.5″ SATA to USB 3.0, M.2 NVMe to USB 3.0, M.2 SATA to USB 3.0, and mSATA to USB 3.0 adapters. In addition, I’d recommend checking out this³ article with some recommended SSDs; in particular, this⁴ 120 GB Kingston A400 SATA 3 2.5” Solid State Drive coupled with this⁵ StarTech 2.5″ SATA to USB 3.0 Adapter, which also has the added bonus of giving you far better speeds than a microSD card would! As the author of that article mentions:

“The Kingston A400 drive performs really well in the Raspberry Pi Storage Benchmarks⁶. It’s a great drive and is cheaper than many mid-range MicroSD cards.

The 2.5″ SATA to USB adapter above allows us to do this. There is no power adapter needed as SSDs are low power and are powered by the Pi through USB.”

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¹ — https://jamesachambers.com/raspberry-pi-4-usb-boot-config-gu...

² — https://www.tomshardware.com/how-to/boot-raspberry-pi-4-usb

³ — https://jamesachambers.com/raspberry-pi-storage-benchmarks-2...

⁴ — https://www.amazon.com/dp/B01N6JQS8C/

⁵ — https://www.amazon.com/dp/B00HJZJI84/

⁶ — https://storage.jamesachambers.com/

Ah, just saw that Jeff Geerling (the author of the linked article in this HN post) also has an article about booting the Raspberry Pi 4 from an SSD located here¹ (HN thread here²).

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¹ — https://www.jeffgeerling.com/blog/2020/im-booting-my-raspber...

² — https://news.ycombinator.com/item?id=23471729

For 2-3 years I had a tower (1m height) with 8 RP3s, 4 thinker boards and about 12 Orange Pis (different models). I did run different BOINC projects on it. So the load was 100% 24/7.

The whole time I had 1 or 2 broken SD cards. Temperature was never an issue.

I put on all SBCs just a passive heatsink (about 30x30x20mm). I installed packs with 4 boards vertical. On the bottom I had 2 large fans for all the SBCs. (sorry no picture)

A good approach used in industrial/embedded applications: use a read-only root volume. If you don't write to your SD, you don't wear it out and have no risk of file system corruption either. It's quite a lot of work though, since most packages assume they're installed on a writeable file system.

Debian wiki has a (pretty bad and outdated) page on the subject https://wiki.debian.org/ReadonlyRoot#Enable_readonly_root

At the bottom of this thread the official response from SanDisk support is that all cards except the High Endurance are not supported for Raspberry/Linux:

https://www.raspberrypi.org/forums/viewtopic.php?p=1158010

I've been using them for the last couple years and haven't had any dead Pis, unlike what happened with a couple other "regular" sd cards.

The easiest is to eliminate the SD card by either booting from network, move the rootfs to a USB drive, or boot from a USB drive (now available for Pi 4 with beta firmware). These are documented at https://www.raspberrypi.org/documentation/hardware/raspberry...

My original pi has been corrupting SD cards all the time, especially now that I am running pi hole on it which seems to need more RAM than is available on my old board.

Either network boot or SSD boot. The SD cards do eventually die. I've lost two already

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