[highwaylights]

Question for you about this as I've often considered it.

What is the life of a yubikey? Do they degrade over time horizons?

The reason I ask is that if you have a backup that you never hope to use it's likely to be accessed only very rarely - which makes me kind of wonder what if your primary yubikey fails in 15 years due to natural wear/tear/degradation due to the passage of time and your backup has succumbed to the same problem due to being just as old?

[mrsteveman1]

> What is the life of a yubikey? Do they degrade over time horizons?

I don't think it's an issue in practice, certainly not for someone using them as they were intended, even heavily, but in theory a JavaCard implementation (like most of the smart card ecosystem, Yubikeys are still JC devices as far as I know) could "wear out" from use because of the way they work internally[1].

I've never personally seen that happen, and all of my Yubikeys still work, even the ones I bought over 10 years ago which were used far more heavily (20-30 ssh/gpg/piv operations per hour, every day, for years) than most people would use a FIDO key.

I've only managed to break other manufacturers smart cards by severely misusing them (as a USB-connected Linux HWRNG, I doubt the RNG command was designed to be called every few seconds for years).

[1] The JavaCard standard requires certain (all? I can't remember, it's been a while) objects in applet code to be written to persistent storage (meaning flash/eeprom), which has endurance limits. In practice they're not expected to be treated as permanent storage devices, if a card fails it's supposed to be replaced with another, revoke the old key pairs, register the new ones, etc.

[jhugo]

It's solid state electronics, if not subject to any external factor (which should not be common to both) it will just keep working on any timescale that matters here.

I've carried one in my pocket for ~10 years without a problem, now I want to replace it because it's too old to support ed25519. That's likely a fraction of its useful hardware life.

[jwr]

> What is the life of a yubikey? Do they degrade over time horizons?

Not that I could see over about 4 years. I've been using one YubiKey (USB-A) for over four years now and a second one (USB-C) for over two. Each has been carried with my keys for at least two years.

But the right approach anyway is to use this excellent tutorial: https://github.com/drduh/YubiKey-Guide and generate your keys yourself, storing a backup in a secure location. This is what I do — so even if my keys get completely destroyed, it will be possible to recreate them from backup.