src/config/replicator.rst

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.. highlight:: ini

==========
Replicator
==========

.. _config/replicator:

Replicator Database Configuration
=================================

.. config:section:: replicator :: Replicator Database Configuration

    .. versionadded:: 1.2

    .. config:option:: max_replication_retry_count

        Maximum replication retry count can be a non-negative integer or
        "infinity"::

            [replicator]
            max_replication_retry_count = 10

    .. config:option:: worker_batch_size

        With lower batch sizes checkpoints are done more frequently. Lower
        batch sizes also reduce the total amount of used RAM memory::

            [replicator]
            worker_batch_size = 500

    .. config:option:: worker_processes

        More worker processes can give higher network throughput but can also
        imply more disk and network IO::

            [replicator]
            worker_processes = 4

    .. config:option:: http_connections

        Maximum number of HTTP connections per replication::

            [replicator]
            http_connections = 20

    .. config:option:: connection_timeout

        HTTP connection timeout per replication.
        Even for very fast/reliable networks it might need to be increased if
        a remote database is too busy::

            [replicator]
            connection_timeout = 30000

    .. config:option:: retries_per_request

        If a request fails, the replicator will retry it up to N times::

            [replicator]
            retries_per_request = 10

    .. config:option:: socket_options

        Some socket options that might boost performance in some scenarios:

        - ``{nodelay, boolean()}``
        - ``{sndbuf, integer()}``
        - ``{recbuf, integer()}``
        - ``{priority, integer()}``

        See the `inet`_ Erlang module's man page for the full list of options::

            [replicator]
            socket_options = [{keepalive, true}, {nodelay, false}]

        .. _inet: http://www.erlang.org/doc/man/inet.html#setopts-2

    .. config:option:: checkpoint_interval

        .. versionadded:: 1.6

        Defines replication checkpoint interval in milliseconds.
        :ref:`Replicator <replicator>` will :get:`requests </{db}>` from the
        Source database at the specified interval::

            [replicator]
            checkpoint_interval = 5000

        Lower intervals may be useful for frequently changing data, while
        higher values will lower bandwidth and make fewer requests for
        infrequently updated databases.

    .. config:option:: use_checkpoints

        .. versionadded:: 1.6

        If ``use_checkpoints`` is set to ``true``, CouchDB will make
        checkpoints during replication and at the completion of replication.
        CouchDB can efficiently resume replication from any of these
        checkpoints::

            [replicator]
            use_checkpoints = true

        .. note::
            Checkpoints are stored in :ref:`local documents <api/local>`
            on both the source and target databases (which requires write
            access).

        .. warning::
            Disabling checkpoints is **not recommended** as CouchDB will scan
            the Source database's changes feed from the beginning.

    .. config:option:: cert_file

        Path to a file containing the user's certificate::

            [replicator]
            cert_file = /full/path/to/server_cert.pem

    .. config:option:: key_file

        Path to file containing user's private PEM encoded key::

            [replicator]
            key_file = /full/path/to/server_key.pem

    .. config:option:: password

        String containing the user's password. Only used if the private keyfile
        is  password protected::

            [replicator]
            password = somepassword

    .. config:option:: verify_ssl_certificates

        Set to true to validate peer certificates::

            [replicator]
            verify_ssl_certificates = false

    .. config:option:: ssl_trusted_certificates_file

        File containing a list of peer trusted certificates (in the PEM
        format)::

            [replicator]
            ssl_trusted_certificates_file = /etc/ssl/certs/ca-certificates.crt

    .. config:option:: ssl_certificate_max_depth

        Maximum peer certificate depth (must be set even if certificate
        validation is off)::

            [replicator]
            ssl_certificate_max_depth = 3