I got this query while distrohopping. On Linux I have to enter my password erveytime I boot to decrypt the disk. But on windows I never had to do it. The first time windows bitlocker asked for password was when I booted into windows after installed Linux. Why is it so?
There’s other approaches to automatically unlocking. For example, you can combine Clevis with Tang to use Network Bound Disk Encryption, which lets you automatically decrypt only when on a trusted network. (the password is stored on a different system on the same network)
You can have multiple different LUKS keys, and any of them can be used to decrypt the disk. This lets you automatically unlock via a network server when your system is at home, while still prompting for an unlock password when not at home.
At my workplace, our laptops have two LUKS keys - one for me and one for IT / tech support. It lets IT boot the system (eg if I send it in for repair) without having to know my LUKS password.