MPP

MPP Web Service

MPP was written as a 2nd party plugin to controllers. These controllers are what enact the physical change of state of MySQL nodes.

• MPP has been tested under the following controllers:
  • Linux Virtual Server
  • Red Hat Clustering Suite, Piranha
  • F5 Network SmartDNS
  • F5 Network Big IP
  • MySQL Proxy (work completed r1.0.1, initial testing completed r1.0.3)

The PERL requirements for using MPP is as follows:

  MODULE	MIN VERSION	AVAILABLE
  -----------	-----------	--------------
  CGIbasic	0.010		MPP Bundled
  Config_info	1.00803		MPP Bundled
  LogBasic	0.00.003	MPP Bundled
  Storable	PERL >= 5.8	PERL Bundled
  Net::HTTP	PERL >= 5.8	PERL Bundled
  Net::Ping	PERL >= 5.8	PERL Bundled
  IO::FILE	PERL >= 5.8	PERL Bundled
  DBD::MySQL	2.9006		CPAN
  DBI		1.46		CPAN

The PERL requirements for using the MPP Web Service is as follows:

• Web Service
  • Data::Dump
  • XML::TreePP
  • XML::TreePP::XMLPath
• Web Client
  • Data::Dump
  • XML::TreePP
  • XML::TreePP::XMLPath
  • XML::XSLT
  • XML::Tidy
  • CGI
  • JSON::PP

This software was recently imported from our internal engineering lab, and has been merged with modification recomendations from our real world implementation. The resulting code available here has been tested and considered ready for release.

Documentation

• MySQL Failover Strategy using State Management, introducing MPP - Part 1
  Having a strategy for failover has become almost standard in the business world. Whether it is a total site failover from a NOC in one city to another, or just a simple redundant server. Over the years many technology solutions have been created for or adopted to MySQL to provide this type of strategy.
  
  
• MySQL Failover Strategy using State Management, introducing MPP - Part 2
  In Part 1 we have seen how the concept of state management works. Now it's time to apply that concept to a load-balancer. In this Part 2 we will look at a strategy for using Linux Virtual Server with MPP for failover, and also take a closer look at the mechanics of MPP itself.
  
  
• MySQL Failover Strategy using State Management, introducing MPP - Part 3
  In part 2 we discussed the internals of MPP and how MPP can be used with LVS to create a failover strategy. In this part 3 we will discuss how to configure and operate MPP, and additionally use MPP with MySQL Proxy to create a failover strategy.
  
  

Get the code

You can download the source code from Subversion.

• Subversion trunk: https://dev.codepin.org/svn/mpp/trunk/mpp
• Subversion tags (revisions): https://dev.codepin.org/svn/mpp/tags/mpp
• Latest Revisions:

  date	revision	tarball	summarized description
  2007.12.10	1.0.3	mpp-1.0.3.tgz	mysql-polld daemon-like script is created for the replacement of the cron option for polling nodes. Initial testing for integration with MySQL Proxy 0.6.0 has been completed. Various fixes and updates.
  2007.11.16	1.0.2	mpp-1.0.2.tgz	The mpp.lua file has been updated to address an issue I refer to as "all_node_down", where all Proxy backend servers are down and MPP cannot connect to load its evaluations into Proxy. This version also address the issue where you could not supply a blank password to mpp-proxyadmin.pl. This version also contains a work around for MySQL Bug #32464 for DBD::mysql.
  2007.11.13	1.0.1	mpp-1.0.1.tgz	Integration with MySQL Proxy Tested. Added a mysqlproxy host module into the API set, mpp.lua Lua script for MySQL Proxy, and created an admin application mpp-proxyadmin.pl to manage MPP evaluations from MPP cache into Proxy internals.
  2007.11.11	1.0.0	mpp-1.0.0.tgz	First release. Integration with Linux Virtual Server and F5 Networks BigIP tested.

The code for MPP Web Service is available for download:

• Web Service revisions: https://dev.codepin.org/svn/mpp/tags/mpp-ws
• Web Service Latest Revisions:

  date	revision	tarball	summarized description
  2009.06.30	0.0.1-gamma	mpp-ws-0.0.1-gamma.tgz	First release. A read-only dashboard to MPP Monitoring data.

There is a plan in progress that MPP will be combined into MySQL Proxy. The plan is multi-phased:

1. MPP revision 1.0.1 gave us MySQLProxy+MPP combination by handshake - getting them to talk to each other.
2. MPP Revision 1.0.3 gave us a daemon to perform the polling, rather than relying on cron for implementation
   Depending on how MySQL Proxy evolves, one of the two will happen:
   1. A newer web 2.0 enabled polling manager daemon process
   2. Polling managed by Proxy, and manageable through a web 2.0 interface
3. We want these load balancing methods in MySQL Proxy using Lua, and relying on MPP for the logic:
   • round robin (this is the default, and currently the only implementation)
   • read-only versus read-write, SQL query load balancing (this is the next desired implementation)
   • weighted connections
   • least connections
   • weighted least connections
4. Depending on the future development of MySQL Proxy, the following may happen:
   1. Parts of MPP converted in Lua Snipits using PERL Inline::Lua; Lua Snipts integrated into MySQL Proxy.
   2. Merging of MPP into MySQL Proxy without external dependencies, with the following attributions:
      • MPP-as-Lua still packageable into a MPP PERL-library using Inline:Lua for 2nd party integration into other controllers.
      • MPP Clients can/will be written for managing MPP logic in a running MySQL Proxy implementation of MPP.
             (This allows the administrator to say, "Uh.. change your mind to make this decision instead." Ex: "I don't care if the STANDBY is in [replication] FAILure, promote it to ACTIVE and fail-over to it anyway.")