This guide describes how to enable secure communication between client and server using SASL mechanism. ZooKeeper supports Kerberos or DIGEST-MD5 MD5 as your authentication scheme.

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ZOOKEEPER-938 is the JIRA issue, and the patch is available linked from that JIRA. Note that this JIRA only describes client-server mutual authentication.

ZooKeeper ACLs and SASL

This proposed implementation builds on the existing ZooKeeper authentication and authorization design in a straightforward way. To briefly review, ZooKeeper supports pluggable authentication schemes. A node may have any number of <scheme:expression,perms> pairs. The left member of the pair specifies authentication as the authentication scheme and the principal. The right member indicates what permissions are given to this principal. For example, one ACL pair on a given node might be:

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