This release:

- Fixes a regression in IPv6 address handling

- Allows you to disable request logging via the following optional
    settings:

    - `opscode-erchef['enable_request_logging']`
    - `oc_bifrost['enable_request_logging']`
    - `bookshelf['enable_request_logging']`

    See the [Chef server optional
    settings](/server/config_rb_server_optional_settings/) guide for
    additional details

- `chef-server-ctl reconfigure` fixes permissions on gems with an
    overly restrictive umask

- Makes the display of the welcome page configurable via the
    `nginx['show_welcome_page']` setting. See the [Chef server optional
    settings](/server/config_rb_server_optional_settings/) guide for
    additional details

- Infers the current database migration level and necessary upgrades
    for `chef-server-ctl upgrade`

- Catches `server_name` resolution errors during
    `chef-server-ctl reconfigure`, and continues with the
    reconfiguration

- No longer creates the default RabbitMQ `guest` user

See the detailed [change
log](https://github.com/chef/chef-server/blob/master/CHANGELOG.md#121715-2017-12-21)
for a complete list of changes.