Log Setup for Elasticsearch 2.3.3

To customize the logging format and behavior for ES 2.3.3, update its configuration file: /etc/elasticsearch/logging.yml

In its default location, logging has the needed ownership. Choose a separate, dedicated partition of ample size to move the log directory and make the elasticsearch user the owner of that directory:
```
chown -R elasticsearch:elasticsearch <path_to_log_directory>
```

Best practice - For better archiving and compression than the built-in log4j, turn off the rotation of log4j and use logrotate.

Edit the logging.yml to limit the amount of space consumed by Elasticsearch log files in the event of an extremely high rate of error logging.
Locate the file: section and make these changes:

Before

file:
    type: dailyRollingFile
    file: ${path.logs}/${cluster.name}.log
    datePattern: "'.'yyyy-MM-dd"
...

After

file:
    type: rollingFile                        # change from dailyRollingFile
    maxBackupIndex: 0
    maxFileSize: 1000000000                  # 1 GB
    file: ${path.logs}/${cluster.name}.log
    # datePattern: "'.'yyyy-MM-dd"           # remove
...

Repeat for the deprecation and slowlog log files, as appropriate:

  deprecation_log_file:
    type: rollingFile
    file: ${path.logs}/${cluster.name}_deprecation.log
    layout:
      type: pattern
      conversionPattern: "[%d{ISO8601}][%-5p][%-25c] %m%n"
    maxBackupIndex: 0
    maxFileSize: 1000000000 # (1GB)

  index_search_slow_log_file:
    type: rollingFile
    file: ${path.logs}/${cluster.name}_index_search_slowlog.log
    layout:
      type: pattern
      conversionPattern: "[%d{ISO8601}][%-5p][%-25c] %m%n"
    maxBackupIndex: 0
    maxFileSize: 1000000000 # (1GB)

  index_indexing_slow_log_file:
    type: rollingFile
    file: ${path.logs}/${cluster.name}_index_indexing_slowlog.log
    layout:
      type: pattern
      conversionPattern: "[%d{ISO8601}][%-5p][%-25c] %m%n"
    maxBackupIndex: 0
    maxFileSize: 1000000000 # (1GB)