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1. use gpg2 --gen-key to generate a new key. Make sure that the key size is 4096 bits, the key doesn't expire, and use CODE SIGNING KEY for the comment.
2. Now you need to register your key at http://pgp.mit.edu/ using the output of gpg --armor --export <keyid>
3. Add your key to the KEYS file:
   1. svn co https://dist.apache.org/repos/dist/release/zookeeper/ zookeeper_dist
   2. cd zookeeper_dist.
   3. edit the KEYS file. See the top of the KEYS file for instructions on how to edit this file
   4. svn ci
4. Upload digest to your account on id.apache.org (gpg2 --fingerprint)

If you have any issues (i.e. "error: gpg failed to sign the data") when trying to sign your commit (tag), refer to this gist.

Useful Links and Background:

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