== link:index.html[Index] -> link:cookbook.html[Cookbook]

Cookbook: Managing logs
-----------------------

Cherokee strictly follows a
link:other_goodies.html#zero-downtime[downtime-free] policy. This also
applies to the process of log rotation. No need to interrupt any
active connections just to do this.

This operation involves using
link:other_bundle_cherokee-tweak.html[cherokee-tweak] and the
link:modules_handlers_admin.html[remote administration] handler.

Logging is an operation performed on a per-virtual-server basis, so
rotation must also be done this way. For simplicity's sake we'll make
an example with just the default virtual server present, but the
process is exactly the same for more. Independently of the number,
just one rule is needed as entry point for the handler.

Under the hood, the process is simple:

- Set Cherokee to backup mode, which will start logging to an internal buffer.

- Locally rotate the logs: this operation is not performed by the web server.

- Restore Cherokee to production mode, dumping the logs in the buffer
  to the new file and continuing with business as usual.

You must be very careful when setting up cherokee-admin. Security
should be of concern, since unauthorized access could in theory keep
the server in backup mode until it runs out of auxiliary buffer space.

cherokee-admin
~~~~~~~~~~~~~~
First, the remote administration handler must be configured, so we
will have to create a rule for that (`Virtual Servers` -> `default` ->
`Behavior` -> `Rule Management` -> `Add New`). We will use a
directory-type rule.

[options="header"]
|=======================
|Rule Type |Web Directory
|Directory |/admin
|Handler   |`Remote Administration`
|=======================

.Handler
image::media/images/cookbook_managing_logs_handler.png[Handler]

This handler will allow performing administration tasks, so public
access is not an option. You can leave free access, but you should
not. Don't forget to fill in the `Security` tab of
the rule to specify a validation method. Using `Digest` mechanism and
restricting to only allow HTTPS connections  is also strongly advised.

In this example, we will use the simplest of all, the `Fixed list`
validation mechanism and will define the user `admin` identified by
the password `adminpass`. Of course you can use any other method
available.

.Security options
image::media/images/cookbook_managing_logs_security.png[Security]

.Possible list of rules
image::media/images/cookbook_managing_logs_rules.png[Rules]

Remember to save the changes through a graceful restart, since the main
purpose of this recipe is not loosing any logging information and
keeping the server online.

cherokee-tweak
~~~~~~~~~~~~~~
To actually rotate the logs, you must use `logrotate` as command
parameter.

Provided the user running cherokee-tweak has sufficient permissions,
the rotation will be effective. Just provide the required parameters:

. command, which is `logrotate`

. url, the administration URL

. log, the log file to be rotated

. user and password, since the administration interface has restricted
  access.


.cherokee-tweak parameters
-----
$ cherokee-tweak -c logrotate -a http://example.net/admin/ -u admin -p adminpass -l /var/log/cherokee.access
-----

.Command output
-----
Setting backup mode.. OK
Log file '/var/log/cherokee.access' moved to '/var/log/cherokee.access.1' successfully
Restoring production mode.. OK
-----

That should do it. link:other_bundle_cherokee-tweak.html[cherokee-tweak] is
a powerful tool. Take a look at the parameters and you find out if it
can solve some of your administration problems.
