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Comment by _gfrc | Hacker News Reader

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.

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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)

> 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.

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.

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