Hi all,

Can anyone tell me how long SD cards last in read-only mode?
I've had this embedded SD card Linux installation running on a Raspberry Pi for over 10 years now and it's been flawless so far. The card is only read-from (has the tab in the RO mode position) as there's no need for anything to be written to it in this app. I'm just wondering how long it'll continue to function for? Do these cards need to be 'refreshed' by overwriting every so many years or are they good for 'life' -whatever that is?
Many thanks,

CC.

As long as you have a good back up, like a duplicate card, I wouldn't worry too much, but to answer your question, it likely depends on the quality of the card.

(I think 10 years is a long time, & I for sure would ensure you have that back up.)

I guess it depends on how many times do you switch it on and off too, otherwise it may work for 20 years or even more. As it was mentioned a good (working) backup will help in case of a trouble.

Unfortunately it won't. The application is within a safe and the Pi has the job of enabling it to be opened at certain restricted times only. So if the card fails, it won't be possible to get access to the Pi and the failed card. They'll be locked away with the rest of the contents until such time as the safe is broken open by force, which will be messy and costly.

IIRC, the old floppy disks were prone to losing data over relatively short periods of time. I'd hoped for better from SD cards. I'm just wondering if re-writing the card afresh would set the clock back and give it a new lease of life?

Why not 'open' the safe, remove the card, copy the card, replace the card. And your good for another 10 years or so with piece of mind . They are so cheap. Replace once a year if you want... I am starting to use those white Sandisk high endurance SD cards for my PIs that use SD cards (some boot from a USB SSD drive which is another option). Not the speediest but I think more 'reliable'. Actually I don't think the problem is so much reading, but writing data. It is why an SSD usually has a TBW (Terabytes written) rating before the SSD starts to degrade. Constantly powered up 'should' be good for years if just reading.

The question I have is build up of heat in a sealed safe.... Which brings me to the next question of a power cord that must be routed inside. How does 'that' work for a safe?

Here's a video about storage life expectancy:

https://www.youtube.com/watch?v=xA9Xq7hb6Q0

Thanks, all. Looks like I really am pushing my luck with this card at 10 years and need to do an urgent refresh!

As far as I see it is a serious risk by itself. Not only the card can die, but the Pi itself too. But I think it is another story

An SD card is not very reliable despite what the OEM say MTBF.