How to decrypting with a Master Key

[Truong Chuong Duong]

I'm following the instruction on https://docs.bareos.org/TasksAndConcepts/DataEncryption.html#generating-private-public-encryption-keys

The backup file is encrypted as well, but I have no ways to decrypt by the master key.

The instruction says:

Set the PKI Keypair statement in your bareos configuration file:

PKI Keypair = master.keypair

But I cannot found that configuration file, I tried to add that line to all configuration files one by one but none of them work.

Where shall I put my master keypair to decrypt the backup file?