Book: How to Configure Server Security
Revision: 6bff93b8
Section: 3.1.2. Secure the Management Interfaces with a New Identity Store

Issue description:
In procedure in 3.1.2. Secure the Management Interfaces with a New Identity Store there is step 3. Add GSSAPI to the configured configurable-sasl-server-factory. It is very confusing why GSSAPI should be added. Step 3. should be rewritten:

• Make it "Optional" step and says something like "some pattern-filter can be added to configured configurable-sasl-server-factory".
• There should be also explained "why this pattern-filter should be added".
• Current content of step 3. should be whole transformed to example "Example Add GSSAPI to the configured configurable-sasl-server-factory" with current CLI command (in the same way how are examples used in step 4.).

Suggestions for improvement:
Already mentioned in Issue description.