Compose Database-as-a-Service Help and Documentation

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etcd on Compose

Introducing etcd

If you're familiar with Linux, you might already have an idea what etcd may be about. A typical Linux filesystem contains a few common directories.

The essentials include:

  • /bin for common files, shared among the machine's users.
  • /boot is where your all important start-up files and the kernel live.
  • /home is where your personal stuff is.
  • /var for variable and temporary files. You may know /var as "where your logs are".

Then, there is /etc. The command centre of your Linux environment. Within /etc, you will find all of your configuration files; each file that governs a programs behaviour is located here. Etcd takes the power of centralized configuration files and allows it to distribute across various members in a cluster. It's /etcdistributed.

etcd uses HTTP-based REST logic and syntax for communication to the cluster. By using PUTS, GETS and DELETE, you can add, edit, and remove keys and values. A variety of special features, outlined in the next section, provide powerful tools for configuration management.

Special Features

While there is much be interested in with etcd, a few of the most useful perks are:

  • Wait For Changes: By sending GET requests with a 'wait=true' enabled, you will actively poll the queried key until the value changes. You will know immediately when values in your deployment have changed.
  • Time-To-Live: Directories can be created with a TTL value - a set expiry date. Working with encryption, or distributed configuration management is a great fit for etcd.
  • Acid Compare-And-Swap & Compare-And-Delete: An all-or-nothing agreement is required before swapping or deleting key values - the requests and the clusters state is considered before swap and delete operations are executed. Failure to reach consensus returns an HTTP error.

Compose etcd deployments

We provide 5 capsules for your initial etcd cluster:

  • 3 etcd data members
  • 2 hybrid haproxy/etcd proxy instances for high-availability.

  • Each data member starts with 256MB of RAM.

  • IP Whitelisting, Private VLANs.

  • 24/7 Support.
  • Automatic backups.

Pricing for an initial deployments is $28.50, scaling at $19.50 for each additional 256MB of memory.

Datacenter Availability

See Compose Datacenter Availability for current location availability.

SSL and etcd

Compose uses SSL to help protect your etcd connections. Self-signed certificates are deployed to allow for certificate pinning. Consult Connecting to etcd for details.

etcd Playground

If you're looking to learn the basics of etcd, why not explore the basics within our Etcd Playground?

Additional Resources and Related Articles

The full list of documentation for etcd is in the sidebar, in addition to all things Compose.

For more than just help docs, check out Compose Articles and our curated collection of etcd-related topics for more how-to's and information on etcd on Compose.


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etcd on Compose