Metadata-Version: 1.1
Name: couchdb-cluster-admin
Version: 0.4.1
Summary: Utility for managing multi-node couchdb 2.x clusters
Home-page: https://github.com/dimagi/couchdb-cluster-admin
Author: Dimagi
Author-email: dev@dimagi.com
License: BSD License
Description-Content-Type: UNKNOWN
Description: couchdb-cluster-admin
        =====================
        
        utility for managing multi-node couchdb 2.x clusters
        
        First, put together a config file for your setup
        ================================================
        
        This will make the rest of the commands simpler to run. Copy the example
        
        ::
        
            cp config/conf.example.yml config/mycluster.yml
        
        and then edit it with the details of your cluster.
        
        Setting up a local cluster to test on
        =====================================
        
        If you have docker installed you can just run
        
        .. code:: bash
        
            docker build -t couchdb-cluster - < docker-couchdb-cluster/Dockerfile
        
        to build the cluster image (based on klaemo/couchdb:2.0-dev) and then
        run
        
        .. code:: bash
        
            docker run --name couchdb-cluster \
              -p 15984:15984 \
              -p 15986:15986 \
              -p 25984:25984 \
              -p 25986:25986 \
              -p 35984:35984 \
              -p 35986:35986 \
              -p 45984:45984 \
              -p 45986:45986 \
              -v $(pwd)/data:/usr/src/couchdb/dev/lib/ \
              -t couchdb-cluster \
              --with-admin-party-please \
              -n 4
        
        to start a cluster with 4 nodes. The nodes' data will be persisted to
        ``./data``.
        
        To run the tests (which require this docker setup), download and install
        https://github.com/sstephenson/bats
        
        .. code:: bash
        
            git clone https://github.com/sstephenson/bats.git
            cd bats
            ./install.sh /usr/local  # or wherever on your PATH you want to install this
        
        and then
        
        .. code:: bash
        
            docker start couchdb-cluster  # make sure this is running and localhost:15984 is receiving pings
            bats test/
        
        Optional: Set password in environment
        =====================================
        
        If you do not wish to specify your password every time you run a
        command, you may put its value in the ``COUCHDB_CLUSTER_ADMIN_PASSWORD``
        environment variable like so:
        
        ::
        
            read -sp Password: PW
        
        Then, for all commands below prefex the command with
        ``COUCHDB_CLUSTER_ADMIN_PASSWORD=$PW``, e.g.
        
        ::
        
            COUCHDB_CLUSTER_ADMIN_PASSWORD=$PW python couchdb-admin-cluster/describe.py --conf mycluster.yml
        
        Get a quick overview of your cluster
        ====================================
        
        Now you can run
        
        ::
        
            python couchdb_cluster_admin/describe.py --conf config/mycluster.yml
        
        to see an overview of your cluster nodes and shard allocation. For
        example, in the following output:
        
        ::
        
            Membership
                cluster_nodes:  couch3  couch1  couch4  couch2
                all_nodes:  couch3  couch1  couch4  couch2
            Shards
                                   00000000-1fffffff  20000000-3fffffff  40000000-5fffffff  60000000-7fffffff  80000000-9fffffff  a0000000-bfffffff  c0000000-dfffffff  e0000000-ffffffff
                mydb                    couch1             couch1             couch1             couch1             couch1             couch1             couch1             couch1
                my_second_database      couch1             couch1             couch1             couch1             couch1             couch1             couch1             couch1
        
        you can see that while there are four nodes, all shards are currently
        assigned only to the first node.
        
        Help estimating shard allocation
        ================================
        
        In order to plan out a shard reallocation, you can run the following
        command:
        
        .. code:: bash
        
            python couchdb_cluster_admin/suggest_shard_allocation.py --conf config/mycluster.yml --allocate couch1:1 couch2,couch3,couch4:2
        
        The values for the ``--allocate`` arg in the example above should be
        interpreted as "Put 1 copy on couch1, and put 2 copies spread across
        couch2, couch3, and couch4".
        
        The output looks like this:
        
        ::
        
            couch1  57.57 GB
            couch2  42.15 GB
            couch3  36.5 GB
            couch4  36.5 GB
                                 00000000-1fffffff     20000000-3fffffff     40000000-5fffffff     60000000-7fffffff     80000000-9fffffff     a0000000-bfffffff     c0000000-dfffffff     e0000000-ffffffff
            mydb                couch1,couch2,couch4  couch1,couch2,couch3  couch1,couch3,couch4  couch1,couch2,couch4  couch1,couch2,couch3  couch1,couch3,couch4  couch1,couch2,couch4  couch1,couch2,couch3
            my_second_database  couch1,couch3,couch4  couch1,couch3,couch4  couch1,couch3,couch4  couch1,couch3,couch4  couch1,couch3,couch4  couch1,couch3,couch4  couch1,couch3,couch4  couch1,couch3,couch4
        
        Note, the reallocation does not take into account the current location
        of shards, so it is much more useful in the situation that you're moving
        from a single-node cluster to a multi-node cluster than it is in the
        situation where you're adding one more node to a multi-node cluster. In
        the example above, couch1 would be the single-node cluster and couch2,
        couch3, and couch4 form are the multi-node cluster–to-be. You can
        imagine that after implementing the shard allocation suggested here, we
        might remove all shards from couch1 and remove it from the cluster.
        
        Note also that there is no guarantee that the "same" shard of different
        databases will go to the same node; each (db, shard)-pair is treated as
        an independent unit when making computing an even shard allocation. In
        this example there are only a few dbs and shards; when shards \* dbs is
        high, this process can be quite good at evenly balancing your data
        across nodes.
        
Platform: UNKNOWN
Classifier: Development Status :: 3 - Alpha
Classifier: Environment :: Web Environment
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: BSD License
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 2.7
Classifier: Topic :: Software Development :: Libraries :: Python Modules
