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.. include:: ../../common.defs

.. _admin-monitoring-alarms:

Traffic Manager Alarms
**********************

|TS| signals an alarm when it detects a problem. For example, the space
allocated to event logs could be full or |TS| may not be able to write to a
configuration file.

Email Alarms
============

To configure |TS| to send an email to a specific address whenever an alarm
occurs, follow the steps below:

#. Set :ts:cv:`proxy.config.alarm_email` in :file:`records.config` to the email
   address you want to receive alarm notifications. ::

        CONFIG proxy.config.alarm_email STRING "alerts@example.com"

#. Run the command :option:`traffic_ctl config reload` to apply the configuration changes.

Using a Script File for Alarms
------------------------------

Alarm messages are built into Traffic Server and cannot be changed.
However, you can write a script file to execute certain actions when an
alarm is signaled. Traffic Server provides a sample script file named
``example_alarm_bin.sh`` in the ``bin`` directory which can serve as the
basis for your custom alarm scripts.

Viewing Statistics from Traffic Control
=======================================

You can use :program:`traffic_ctl` to view statistics
about Traffic Server performance and web traffic. In addition to viewing
statistics, you can also configure, stop, and restart the Traffic Server
system. For additional information, refer to :ref:`configure-using-traffic-ctl`
and :program:`traffic_ctl`. You can view
specific information about a Traffic Server node or cluster by
specifying the variable that corresponds to the statistic you want to
see.

To view a statistic, enter the following command:::

        traffic_ctl metric get VARIABLE

where ``variable`` is the variable representing the information you
want to view. For a list of variables you can specify, refer to :ref:`traffic_ctl metrics <traffic-ctl-metric>`.

For example, the following command displays the document hit rate for
the Traffic Server node:::

     traffic_ctl metric get proxy.node.cache_hit_ratio

