关于12c密钥的历史管理

驻跸映辉

今天查一个关于12c新机能的问题时，看在12c的文档有下面的记录。
就是不太明白，TDE master key 的历史记录在什么地方保存。
我11gR2的DB，每回备份取得之后，还要手动备份一个wellat文件。

如果升级到12c以后，就可以不用去备份这个wallet文件，我完成DB备份之后，将来想恢复时，直接恢复就可以了。
DB会自己去找已经保存的TDE master key .

谢谢

Database Advanced Security Guide

3 Configuring Transparent Data Encryption

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About Setting the Hardware Keystore TDE Master Encryption Key

To start using hardware security module-based encryption, you must create a TDE master encryption key that is stored inside the hardware keystore. Oracle Database uses the TDE master encryption key to encrypt or decrypt TDE table keys or tablespace encryption keys inside the hardware security module.

If you have not previously configured a software keystore for Transparent Data Encryption, then follow the steps in "Setting a TDE Master Encryption Key if You Have Not Previously Configured One". If you have already configured a software keystore for TDE, then you must migrate it to the hardware security module, as described in "Migrating a Previously Configured TDE Master Encryption Key".

Along with the current TDE master key, Oracle wallets maintain historical TDE master keys that are generated after every re-key operation that rotates the TDE master key. These historical TDE master keys help to restore Oracle database backups that were taken previously using one of the historical TDE master keys.
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