NoSQL showdown: MongoDB vs. Couchbase
MongoDB edges Couchbase Server with richer querying and indexing options, as well as superior ease of use
For gathering statistics and managing a Couchbase Server cluster, the Couchbase Web Console -- available via any modern browser on port 8091 of a cluster member -- is the place to go. It provides a multitab view into cluster mechanics. The tabs include:
- Cluster overview, which has general RAM and disk usage information (aggregated for the whole cluster). Also, operations per second bucket usage. The information is presented in a smoothly scrolling line graph.
- Server nodes, which provides information similar to the above, but for individual members of the cluster. You can also see CPU usage and swap space usage. On this tab, you can add a new node to the cluster: Click the Add Server button and you're prompted for IP address and credentials.
- Data buckets, which shows all the buckets on the cluster. You can see which nodes participate in the storage of a given bucket, how many items are in each bucket, RAM and disk usage attributed to a bucket, and so on.
The Couchbase Web Console provides much more information than can be covered here. An in-depth presentation of its capabilities can be found in Couchbase Server's online documentation.
For administrators who would rather perform their management duties on the metal, Couchbase provides a healthy set of command-line tools. General management functions are found in the
couchbase-cli tool, which lists all the servers in a cluster, retrieves information for a single node, initiates rebalancing, manages buckets, and more. The
cbstats command-line tool displays cluster statistics, and it can be made to fetch the statistics for a single node (the variety of statistical information retrieved is too diverse to list here). The
cbepctl command lets you modify a cluster's RAM and disk management characteristics. For example, you can control the "checkpoint" settings, which govern how frequently replication occurs.
Other command-line tools include data backup and restore, a tool to retrieve data from a node that has (for whatever reason) stopped running, and even a tool for generating an I/O workload on a cluster member to test its performance.
Couchbase Server is available in both Enterprise and Community editions. The Enterprise edition undergoes more thorough testing than the Community edition, and it receives the latest bug fixes. Also, hot fixes are available, as is 24/7 support (with the purchase of an annual subscription). Nevertheless, the Enterprise edition is free for testing and development on any number of nodes or for production use on up to two nodes. The Community edition, as you might guess, is free for any number of production nodes.