97e59974f3
There were several problems with how the pooler checked out vms with
respect to empty pools, invalid pools, and aliases:
- If the vmpooler config did not contain any aliases and the caller
requested a vm from an empty pool or a non-existent one, the vmpooler
would error with:
NoMethodError - undefined method `[]' for nil:NilClass
If the config contained a non-nil alias section, then:
- If the caller requested a vm from an empty pool and either the vm
didn't have an alias or the aliased pool was empty or non-existent, then
the request for that vm would be silently ignored. The vmpooler would
return 200 if the caller asked for multiple vms and the vmpooler was
able to checkout at least one vm. Otherwise it would return 404.
- Similarly, if the caller requested a vm from a non-existent pool, then
the request was silently ignored.
This commit adds a `pool_names` Set to the config containing all valid
pool names including aliases. This is used to determine whether a
requested template name is valid or not. This is necessary because redis
does not distinguish between empty and non-existent sets, e.g. the
following returns false in both cases:
backend.exists('vmpooler__ready__' + key)
If the caller requests a vm (single or multiple), and any vm references
an invalid pool name, we immediately return 404. Otherwise, we know the
request is for valid pool names, since the vmpooler requires a restart
to change pool names and counts.
We then attempt to acquire each vm, trying to match on pool name or
failing back to aliased pool name, as was the previous behavior.
The resulting behavior is:
- If the caller asks for at least one vm from an unknown pool, then
don't try to checkout any vms and respond with 404.
- If the caller asks for a vm, and at least one pool is empty, then
respond with 503, returning checked out vms back to the pool.
- Otherwise return 200 with the list of checked out vms.
This commit also makes `alias` optional again.
This commit also re-enables tests that were merged in from master, but
originally commented out due to the bugs described above..
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|---|---|---|
| lib | ||
| scripts | ||
| spec | ||
| .gitignore | ||
| .travis.yml | ||
| API.md | ||
| Gemfile | ||
| LICENSE | ||
| Rakefile | ||
| README.md | ||
| vmpooler | ||
| vmpooler.yaml.example | ||
vmpooler
vmpooler provides configurable 'pools' of instantly-available (running) virtual machines.
Usage
At Puppet Labs we run acceptance tests on thousands of disposable VMs every day. Dynamic cloning of VM templates initially worked fine for this, but added several seconds to each test run and was unable to account for failed clone tasks. By pushing these operations to a backend service, we were able to both speed up tests and eliminate test failures due to underlying infrastructure failures.
Installation
Prerequisites
vmpooler requires the following Ruby gems be installed:
It also requires that a Redis server exists somewhere, as this is the datastore used for vmpooler's inventory and queueing services.
Configuration
The following YAML configuration sets up two pools, debian-7-i386 and debian-7-x86_64, which contain 5 running VMs each:
---
:vsphere:
server: 'vsphere.company.com'
username: 'vmpooler'
password: 'swimsw1msw!m'
:redis:
server: 'redis.company.com'
:config:
logfile: '/var/log/vmpooler.log'
:pools:
- name: 'debian-7-i386'
template: 'Templates/debian-7-i386'
folder: 'Pooled VMs/debian-7-i386'
pool: 'Pooled VMs/debian-7-i386'
datastore: 'vmstorage'
size: 5
- name: 'debian-7-x86_64'
template: 'Templates/debian-7-x86_64'
folder: 'Pooled VMs/debian-7-x86_64'
pool: 'Pooled VMs/debian-7-x86_64'
datastore: 'vmstorage'
size: 5
See the provided YAML configuration example, vmpooler.yaml.example, for additional configuration options and parameters.
Template set-up
Template set-up is left as an exercise to the reader. Somehow, either via PXE, embedded bootstrap scripts, or some other method -- clones of VM templates need to be able to set their hostname, register themselves in your DNS, and be resolvable by the vmpooler application after completing the clone task and booting up.
API and Dashboard
vmpooler provides an API and web front-end (dashboard) on port :4567. See the provided YAML configuration example, vmpooler.yaml.example, to specify an alternative port to listen on.
API
vmpooler provides a REST API for VM management. See the API documentation for more information.
Dashboard
A dashboard is provided to offer real-time statistics and historical graphs. It looks like this:
Graphite is required for historical data retrieval. See the provided YAML configuration example, vmpooler.yaml.example, for details.
Command-line Utility
- The vmpooler_client.py CLI utility provides easy access to the vmpooler service. The tool is cross-platform and written in Python.
- vmfloaty is a ruby based CLI tool and scripting library written in ruby.
Build status
License
vmpooler is distributed under the Apache License, Version 2.0. See the LICENSE file for more details.