alt Hacker News> I do love the cloud version of passkeys, but I also have a backup YubiKey
How does this work, exactly? Does you cloud password/key manager allow syncing to the YubiKey?
Or do you register a second passkey that you store on the YubiKey whenever you create a passkey?
If it is the latter, do all services that allow passkey authentication also allow registering multiple passkeys? How many?
> could do two backup YubiKeys [...] keep one YubiKey in a safe deposit box
If you register a new passkey on the primary, do you then have to take the backup YubiKey out of the safe deposit box to put it on it as well?
I haven't seen this kind of question answered when sites prompt me to use passkeys instead of passwords.
I create multiple passkeys for the account: an iCloud passkey and a Yubikey passkey.
Both passkeys are independent of each other and know nothing about each other, only the website knows that both are mapped to the same account.
It's like setting up multiple API keys for a service. Passwords are usually restricted to just one, but passkeys are (generally) allowed to have multiple backups.
When I go to login to Google, for example, it will prompt for a passkey. Currently, in Safari, it will prompt for biometrics on my iCloud passkey. I can either give it my fingerprint/face, or hit the "More options" button, which in the current list allows either 1) insertion of a USB security key, or 2) presenting a QR code that a phone device can scan, allowing use of the passkeys on the phone.
(All very good questions, BTW!)