Definitions

This article is written for use with the Bytemark Cloud Server API.

One API call can provide you with updates about our platform, including information on:

• operating systems for imaging,
• hardware profiles, and
• storage grades.

It does not require authentication.

Endpoints

These are relative to https://uk0.bigv.io

GET /definitions

Attributes

Each set of information contains a text id field and a data field containing an array.

• distributions – The operating systems available to install on Cloud Servers
• storage_grades – Available storage grades for discs
• hardware_profiles – Virtual machine hardware profiles
• keymaps – Keyboard mappings for VNC/SSH
• sendkeys – Used for defining how to send special keys for VNC/SSH
• zone_names – Lists the zones that are available on this cluster

Also included; distribution_descriptions and storage_grade_descriptions

Sections

Storage Grades

Our ‘Archive’, ‘SATA’ and ‘SSD’ storage grades cater to the varying performance requirements that you may have.

• Archive – Cheapest storage; great for low performance requirements.
• SATA – Standard solid state storage (SSD); default for new VMs.
• SSD – Fastest, premium solid state storage (SSD).

Note virtual machines with the the older compatibility2011 hardware profile (see below) might not see much benefit when using SSD’s to the comparatively inefficient storage driver.

Hardware Profiles

Several different hardware profiles are provided for different different performance versus backwards compatibility requirements.

• compatibility2011 – Older QEmu version.
• compatibility2013 – Newer QEmu version – will not (currently) be auto upgraded.
• virtio2011 – Will be upgraded to virtio2013 on restart.
• virtio2013 – Faster, newer version of QEmu; may be auto-upgraded in future.

For consistent behaviour between reboots, choose one of the above compatibility options. The virtio profiles (virtio2013 for example) can be used if you’d prefer to be upgraded automatically on shutdown/restart when a new profile is available. Some operating systems without the appropriate drivers may need the compatibility2011 option.

Zone Names

Lists the zones that are available on this cluster. If you submit a HTTP Authorization:header in your request, you may receive additional zone names.

A zone is a logical collection of resources — heads, tails, VLANs and IP addresses. Those resources may be grouped according to any criteria, but it is envisioned that zones will be initially used to provide geographic resiliency (a zone called ‘manchester’ and a zone called ‘york’, for instance).

A virtual machine’s zone (and its discs) is set at machine creation, and cannot be changed during the lifetime of the virtual machine. Offline migration between zones may be supported at some point, but this will generally require the virtual machine to be renumbered, at the very least.

Example

Request

GET /definitions

Response (success: 200)

[
  {
    "id":"distributions",
    "data":[
      "centos5",
      "centos6",
      "centos7",
      "jessie",
      "precise",
      "symbiosis",
      "trusty",
      "vivid",
      "wheezy",
      "wily",
      "winstd2012",
      "winweb2k8r2"
    ]
  },
  {
    "id":"storage_grades",
    "data":[
      "sata",
      "ssd",
      "archive"
    ]
  },
  {
    "id":"zone_names",
    "data":[
      "manchester",
      "york"
    ]
  },
  {
    "id":"distribution_descriptions",
    "data":{ ... }
  },
  {
    "id":"storage_grade_descriptions",
    "data":{ ... }
  },
  {
    "id":"hardware_profiles",
    "data":[
      "virtio2013",
      "compatibility2013"
    ]
  },
  {
    "id":"keymaps",
    "data":[ ... ]
  },
  {
    "id":"sendkeys",
    "data":[ ... ]
  }
]