==============
MTU detection
==============

Network devices between the bonder and the aggregator can change in ways
that increase or reduce the true (path) MTU. A reduced MTU that is not
accounted for can result in stalled TCP connections, particularly if
those connections are secured with SSL or TLS. An increased MTU that has
not been accounted for will result in slightly decreased bulk transfer
performance.

In either case, MTU detection, which is enabled by default, will
automatically determine the ideal MTU. It will periodically re-check to
account for changes, but sometimes an MTU change is known and needs to
be accounted for right away.

To immediately detect the MTUs for all legs on a bond, navigate to the
bond page and click on the Actions button on the upper right:

|image0|

Then select Detect leg MTUs from the resulting menu:

|image1|

Both the bonder and aggregator will detect the MTUs for the upstream and
downstream paths.

To detect the MTU for a single leg, click the Actions button on the
right side of the leg entry:

|image2|

Then select Detect MTUs from the resulting menu:

|image3|


.. |image0| image:: /attachments/9207887/9437192.png
.. |image1| image:: /attachments/9207887/9437193.png
.. |image2| image:: /attachments/9207887/9437192.png
.. |image3| image:: /attachments/9207887/9437195.png
