How To Set Up A Load-Balanced MySQL Cluster

hausmasta writes "This tutorial shows how to configure a MySQL 5 cluster with three nodes: two storage nodes and one management node. This cluster is load-balanced by a high-availability load balancer that in fact has two nodes that use the Ultra Monkey package which provides heartbeat (for checking if the other node is still alive) and ldirectord (to split up the requests to the nodes of the MySQL cluster)."

Comments

'Ultra Monkey'?

[Anonymous Coward]

One of the major problems with a number of useful open source projects is that their names are terrible for the corporate environment. This is a perfect example of such a project. I sure wouldn't want to pitch the use of this software to a CTO or CIO, even if it was perfect for our database cluster, just because it is called 'Ultra Monkey'. That's just not a professional name, and this product will likely not be taken seriously.

Re:'Ultra Monkey'?

[kryten_nl]

So? Call it the "U.M. system".....

Problem solved.

Re:'Ultra Monkey'?

[Conanymous Award]

But, imagine a Beowulf Cluster of Ultra Monkeys...

Re:'Ultra Monkey'?

[Reality Master 101]

And let's not forget there are plenty of stupid names for succesful, commercial software. [snip bad examples]

You seem to be confusing "literal names" with "good names". What makes a good name isn't that it literally means what it does, it's that it 1) sounds good, and 2) doesn't have negative connotations, and 3) isn't hard to say. It's a bonus if it even vaguely resembles what it does. Lotus Notes, Oracle and Excel all have vague connotations of what they do, but more importantly, there is nothing offensive about them, and they're easy to say and remember.

Compare to some of the popular names in Open Source. GIMP. Gnu (Gah-nu, the absolutely STUPIDEST name and pronounciation ever invented, and that goes for all their programs with the 'g' prefix). Ultra Monkey is right in line with traditional stupid naming.

This is for the MySQL Cluster storage engine

[Jamesday]

This is for the MySQL Cluster storage engine, describing how to set up load balancing across two MYSQL servers that serve as front ends to it.

If you want code to set up a MYSQL cluster (cluster of MYSQL servers NOT using the Cluster storage engine) you might do something like looking at the PHP code in MediaWiki, which does application-level load balancing for reads (not writes) and has so far been tested to 25,000 or so queries per second. Or you could use the same director tools and skip using them for writes, implementing failover for the master server getting the writes.

Re:sounds cool, but MAJOR drawbacks!

[Jamesday]

The sort of thing people use the MySQL Cluster storage engine for include session management and telecoms. That data tends to be of modest size, even for a company with many millions of customers. If you don't mind losing the data if there's a power failure longer than your UPS life you can use the Memory (Heap) storage engine instead of Cluster. You can often back that up wth triggers and reload in a startup script.

The RAM only bit will go away once MySQL 5.1 is released. It's currently in early beta. It doesn't mean you lose your data if there's a power failure; the data is backed up to disk regularly.

Don't forget - The MySQL Protocol is proprietary.

[DAldredge]

The MySQL Protocol is proprietary.

The MySQL Protocol is part of the MySQL Database Management System. As such, it falls under the provisions of the GNU Public License (GPL). A copy of the GNU Public License is available on MySQL's web site, and in the product download.

Because this is a GPL protocol, any product which uses it to connect to a MySQL server, or to emulate a MySQL server, or to interpose between any client and server which uses the protocol, or for any similar purpose, is also bound by the GPL. Therefore if you use this description to write a program, you must release your program as GPL. Contact MySQL AB if you need clarification of these terms or if you need to ask about alternative arrangements.

http://dev.mysql.com/doc/internals/en/licensing-no tice.html

MyPostgres?

[Doc Ruby]

Anyone have an equivalent HowTo for Postgres clusters?

And while I'm getting everything in life I casually ask for, where's the SW that automatically swaps out a MySQL install and replaces it with Postgres, including revising source code that calls/queries the DB, or just uses a MySQL installation as a proxy replica for Postgres nodes in a mixed cluster?