How to Configure Amoeba XML Files for MySQL Proxying

Main Configuration Files

amoeba.xml : Defines how clients connect to Amoeba and basic proxy settings.

dbServers.xml : Lists the databases that Amoeba proxies, including host IP, port, username, and password for each.

rule.xml : Contains sharding rules that tell Amoeba how to split data and merge results.

functionMap.xml : Maps database functions (e.g., UNIX_TIMESTAMP(), SYSDATE()) to Amoeba’s internal handling.

ruleFunctionMap.xml : Defines custom functions used in rule.xml, such as hashing user IDs for sharding.

access_list.conf : Specifies IP addresses that are allowed or denied access.

log4j.xml : Configures logging levels and output formats using Log4j syntax.

Configuration Example

Goal: Use Amoeba to proxy a MySQL instance and verify the proxy works from a client.

Edit $AMOEBA_HOME/conf/dbServers.xml:

Locate the node <dbServer name="abstractServer" abstractive="true">.

Replace port, schema, user, and password with the MySQL connection details.

Edit $AMOEBA_HOME/conf/amoeba.xml:

Find the property node under name="authenticateProvider" and set the user and password that clients will use to connect to Amoeba.

Test the connection:

Run: mysql -uroot -p111111 -h127.0.0.1 -P8066 (8066 is Amoeba’s default port).

Successful login shows a Server version like

5.1.45-mysql-amoeba-proxy-3.0.4-BETA MySQL Community Server (GPL)

, confirming the proxy.

Insert a test row, exit Amoeba, then connect directly to the real MySQL to verify the data.

Configuration File Structure

dbServers.xml

The file defines multiple <dbServer> nodes. The abstract node (e.g., <dbServer name="abstractServer">) holds common settings such as shared credentials and pool parameters. Concrete servers inherit from the abstract node:

<dbServer name="server1" parent="abstractServer">
    <factoryConfig>
        <property name="ipAddress">127.0.0.1</property>
    </factoryConfig>
</dbServer>

Virtual servers can group several physical MySQL instances for read‑only load balancing:

<dbServer name="multiPool" virtual="true">
    <poolConfig class="com.meidusa.amoeba.server.MultipleServerPool">
        <property name="loadbalance">1</property> <!-- 1=ROUNDROBIN -->
        <property name="poolNames">server1,server2</property>
    </poolConfig>
</dbServer>

amoeba.xml

Amoeba presents itself as a MySQL server, so a <server> node configures client connection details. The <dbServerLoader> node tells Amoeba where to load dbServers.xml, and the <queryRouter> node defines routing rules for read/write operations.