================================
Adding and updating aggregators
================================

Adding an aggregator
---------------------

Before installing Bonding on an aggregator, create its configuration in
the web interface.

From the aggregator list click Add aggregator.

|image0|

Provide the following information.

Standard options
+++++++++++++++++

Name
^^^^^

A brief description of the aggregator. This must be unique in the
aggregator's space.

IP
^^^

The IPv4 address that bonders should use to contact the aggregator.

.. warning::

    Do not also add this address as an interface address on the aggregator through the management server or it will conflict with the primary IP and
    gateway defined in /etc/network/interfaces and prevent the aggregator from coming back online after bonding is restarted. If it conflicts with an
    interface address in an aggregator's networking configuration, that aggregator **will not come back online if bonding is restarted**.

    See the `errata section`_ of the 6.5 release notes.


.. _`errata section`: ../release-notes/6.5.html#errata


IPv6
^^^^^^

The IPv6 address that bonders should use to contact the aggregator. An IPv4 address is required even if an IPv6 address is configured.

.. warning::

    Changing the configured address (for either IP version) requires a matching manual configuration change on the node.
    Consult `changing a host IP address <../administration/changing-host-ip-address.html>`__ before changing any configured IP address on an aggregator.


Routing group
^^^^^^^^^^^^^^

The routing group to which the aggregator is assigned.

Serial number
^^^^^^^^^^^^^^

The serial number of the aggregator hardware.

Asset tag
^^^^^^^^^^

The asset tag given to the aggregator hardware.

Space
^^^^^^

The space to which the aggregator is assigned.

Failover monitoring
^^^^^^^^^^^^^^^^^^^^

Enable or disable monitoring for aggregator failures. If enabled, the
management server will reassign the aggregator's bonds to their
secondary aggregators in the event of an aggregator failure or outage.
Defaults for the related settings below are configured from the
`Administration page <../administration/aggregator-failover-settings.html>`__.

Failover interval
^^^^^^^^^^^^^^^^^

The number of seconds between each check sent from the management server
to the aggregator.

Failover receive timeout
^^^^^^^^^^^^^^^^^^^^^^^^

The number of seconds to wait to receive a response from the aggregator.

Failover failure threshold
^^^^^^^^^^^^^^^^^^^^^^^^^^

How many sequential checks must fail before an aggregator is considered
to have failed.

Failover recovery checks
^^^^^^^^^^^^^^^^^^^^^^^^

How many sequential checks must succeed before an aggregator is
considered to have recovered.

Failover max flap checks
^^^^^^^^^^^^^^^^^^^^^^^^

The maximum number of checks that the flap damping technique will
require the aggregator to respond to.

Username
^^^^^^^^

Usually root, the user for management via SSH.

Password
^^^^^^^^

The password for the user specified above.

.. warning::
    The username and password fields are for record-keeping only. You should
    change them only if you manually change the management username or
    password on the aggregator.

Advanced options
++++++++++++++++

The following fields are visible after you click "Show advanced".

.. _proxy ARP:

Proxy ARP
^^^^^^^^^

Enable this if you want the aggregator to proxy ARP requests for IP
addresses assigned to bonders. This is useful in environments where
standard routing using BGP or OSPF is not available.

Metric collection interval
^^^^^^^^^^^^^^^^^^^^^^^^^^

How frequently to query performance metrics, in seconds.

Metric reporting interval
^^^^^^^^^^^^^^^^^^^^^^^^^

How frequently to report collected metrics to the management server, in
seconds.

CPU governor
^^^^^^^^^^^^

Select which algorithm to use for scaling CPU frequencies.
If unset, the last used method for the CPU type will be used or the system default will be used after the system is rebooted.
Selection of an alternate governor, particularly so ``Performance``,
may result in increased throughput on certain platforms.
For a detailed explanation of each governor, see `the documentation <https://www.kernel.org/doc/Documentation/cpu-freq/governors.txt>`__.

TCP congestion control algorithm
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The TCP congestion control algorithm defines the behaviour of node sourced
TCP connections. Currently, there are 14 different algorithms to choose
from when configuring an aggregator on the management server. Prior to 6.4,
CUBIC was the implicit choice. This option has no effect on traffic that is not
originated on the aggregator itself.

#. CUBIC
#. BIC
#. CDG
#. Datacenter TCP
#. Hamilton TCP
#. Hybla
#. Illinois
#. Low priority
#. Reno
#. Scalable TCP
#. Vegas
#. Veno
#. Westwood
#. Yeah TCP
#. BBR

For more information on this topic and the various algorithms refer
to https://en.wikipedia.org/wiki/TCP_congestion_control

Depending on the type of traffic going over a bond, it's possible that a
different algorithm could decrease performance, while others might
improve it. This is most noticable when running speed tests.


Conntrack table size
^^^^^^^^^^^^^^^^^^^^

The maximum number of connections the host can track in its internal
tables. If the number of tracked connections reaches this number, new
connections will be dropped and an entry made in the system log file.

Web server
^^^^^^^^^^

If checked, the aggregator will offer a simple web service to local
networks and trusted remote networks.

.. note::
    As of 2013.6, the web service on the aggregator doesn't actually do
    anything. Its functionality may be expanded in future versions of
    SD-WAN.

Debug
^^^^^

If checked, services running on the aggregator log events in much more
detail than normal. Debug mode is not recommended except on the
recommendation of a technical support agent.

TCP segmentation offloading
^^^^^^^^^^^^^^^^^^^^^^^^^^^

If checked, enables TCP segmentation offloading (TSO) for private WAN
backhaul. Disabling TSO is necessary on some platforms that suffer severe
performance degradation when the backhaul is encrypted.

When the form is complete, click Save.

Updating an aggregator
-----------------------

To update an aggregator, navigate to its details page and click Edit.

|image1|

Change the necessary fields, then click Save.

Removing an aggregator
-----------------------

To remove an aggregator, follow these steps:

#. Assign its bonds to other aggregators.
#. Shut down the aggregator operating system.
#. Navigate to its details page and click delete button.
   |image2|
#. Confirm your action on the dialog that appears.


.. |image0| image:: /attachments/2228254/12877985.png
.. |image1| image:: /attachments/2228254/12877986.png
.. |image2| image:: /attachments/2228254/12877987.png
