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+Data Channel Renegotiation
+--------------------------
+
+When running OpenVPN in client/server mode, the data channel will use a
+separate ephemeral encryption key which is rotated at regular intervals.
+
+--reneg-bytes n
+  Renegotiate data channel key after ``n`` bytes sent or received
+  (disabled by default with an exception, see below). OpenVPN allows the
+  lifetime of a key to be expressed as a number of bytes
+  encrypted/decrypted, a number of packets, or a number of seconds. A key
+  renegotiation will be forced if any of these three criteria are met by
+  either peer.
+
+  If using ciphers with cipher block sizes less than 128-bits,
+  ``--reneg-bytes`` is set to 64MB by default, unless it is explicitly
+  disabled by setting the value to :code:`0`, but this is
+  **HIGHLY DISCOURAGED** as this is designed to add some protection against
+  the SWEET32 attack vector. For more information see the ``--cipher``
+  option.
+
+--reneg-pkts n
+  Renegotiate data channel key after **n** packets sent and received
+  (disabled by default).
+
+--reneg-sec args
+  Renegotiate data channel key after at most ``max`` seconds
+  (default :code:`3600`) and at least ``min`` seconds (default is 90% of
+  ``max`` for servers, and equal to ``max`` for clients).
+  ::
+
+     reneg-sec max [min]
+
+  The effective ``--reneg-sec`` value used is per session
+  pseudo-uniform-randomized between ``min`` and ``max``.
+
+  With the default value of :code:`3600` this results in an effective per
+  session value in the range of :code:`3240` .. :code:`3600` seconds for
+  servers, or just 3600 for clients.
+
+  When using dual-factor authentication, note that this default value may
+  cause the end user to be challenged to reauthorize once per hour.
+
+  Also, keep in mind that this option can be used on both the client and
+  server, and whichever uses the lower value will be the one to trigger
+  the renegotiation. A common mistake is to set ``--reneg-sec`` to a
+  higher value on either the client or server, while the other side of the
+  connection is still using the default value of :code:`3600` seconds,
+  meaning that the renegotiation will still occur once per :code:`3600`
+  seconds. The solution is to increase --reneg-sec on both the client and
+  server, or set it to :code:`0` on one side of the connection (to
+  disable), and to your chosen value on the other side.