mysql_probe

mysql probe

A golang application that checks a mysql database, writing results to flat files and/or runs an HTTP server for haproxy health checks based on those checks

Requirements

• MySQL >= 5.1.12
• Access to a MySQL user with REPLICATION CLIENT permissions (or ability to create one)

Installation

1. Install golang 1.3+
2. go get github.com/haikulearning/mysql_probe

MySQL configuration

Create a MySQL user with the following permissions:

• REPLICATION CLIENT

For example:

CREATE USER 'mysql_probe'@'127.0.0.1' IDENTIFIED BY 'As92rj05UvKK';
GRANT REPLICATION CLIENT ON *.* TO 'mysql_probe'@'127.0.0.1';

Running

$ mysql_probe --help # will provide available commands & flags.
$ mysql_probe start  # will both test mysql and run the HTTP status server.

Checks

For now, a default set of checks are hard-coded to run:

• "Connection Count Less Than X" with the following values:
  • 1, 10, 50, 100, 150, 200, 250, 300, 600, 1200, 2400
• "Replication Delay Less Than X" with the following values (in seconds):
  • 0, 10, 30, 60, 120, 300, 600, 1200, 2400

haproxy Configuration Example

TOOD: Add an example haproxy config using these checks to build a resilient failover configuration.

xinetd Configuration Example

TODO: Add an example of using xinetd to return these http txt files as http requests.

Development

$ get go -u github.com/haikulearning/mysql_probe
$ cd $GOPATH/src/github.com/haikulearning/mysql_probe
$ make

Cross-compiling

If you need to deploy mysql_probe to another platform (i.e. build on OS X, deploy to Linux), Go makes that fairly straightforward!

$ cd $GOPATH/src/github.com/haikulearning/mysql_probe
$ make all
# or target a specific OS
$ make mac
$ make linux

If the above commands aren't working for you, be you've locally installed appropriate Go compilers for the target platforms (here's a Stack Overflow question describing how to install them on OS X).

Testing

A dockerfile is available in docker/test for spinning up an instance of this app.

Roadmap

1. Build checks with completely hardcoded configuration to check localhost.
2. Build configuration parser so this app does not need to be recompiled every time config changes.
3. Build rollup checks into configuration.

Phase 1 hardcoded config

Check config.go for hardcoded values, host, username, password. Run replcation_delay check and output to /var/run/mysql_probe/replcation_delay.http.txt Run connection_count check and output to /var/run/mysql_probe/connection_count.http.txt

Copyright

Copyright 2014 Derek Volker

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.