{"id":66681,"date":"2022-08-24T09:00:34","date_gmt":"2022-08-24T09:00:34","guid":{"rendered":"https:\/\/www.cryptocabaret.com\/?p=66681"},"modified":"2022-08-24T09:00:34","modified_gmt":"2022-08-24T09:00:34","slug":"your-guide-to-distsqls-cluster-governance-capability","status":"publish","type":"post","link":"https:\/\/www.cryptocabaret.com\/?p=66681","title":{"rendered":"Your guide to DistSQL’s cluster governance capability"},"content":{"rendered":"

Your guide to DistSQL’s cluster governance capability <\/span>
\nRaigor Jiang<\/a><\/span>
\nWed, 08\/24\/2022 – 03:00<\/span><\/p>\n

\n
1 reader likes this<\/div>\n
1 reader likes this<\/div>\n<\/div>\n
\n

Apache ShardingSphere 5.0.0-Beta version with DistSQL made the project even more beloved by developers and ops teams for its advantages, such as dynamic effects, no restart, and elegant syntax close to standard SQL. With upgrades to 5.0.0 and 5.1.0, the ShardingSphere community has once again added abundant syntax to DistSQL, bringing more practical features.<\/p>\n

In this article, the community co-authors will share the latest functions of DistSQL from the perspective of cluster governance.<\/p>\n

ShardingSphere clusters<\/h2>\n

In a typical cluster composed of ShardingSphere-Proxy, there are multiple compute nodes and storage nodes, as shown in the figure below.<\/p>\n

\n
\"An<\/div>\n
Image by: <\/span><\/p>\n

(Jiang Longtao and Lan Chengxiang, CC BY-SA 4.0)<\/p>\n<\/div>\n<\/article>\n

To make it easier to understand, in ShardingSphere, we refer to proxy as a compute node<\/em> and proxy-managed distributed database resources (such as ds_0 or ds_1) as resources<\/em> or storage nodes<\/em>.<\/p>\n

Multiple proxy or compute nodes are connected to the same register center. They share configuration and rules, and they can sense each other’s online status. These compute nodes also share the underlying storage nodes, so they can perform read and write operations to the storage nodes at the same time. The user application is connected to any compute node and can perform equivalent operations.<\/p>\n

Through this cluster architecture, you can quickly scale proxy horizontally when compute resources are insufficient, reducing the risk of a single point of failure and improving system availability. The load-balancing mechanism can also be added between the application and compute node.<\/p>\n<\/p>\n

\n
More great content<\/div>\n
\n
Free online course: RHEL technical overview<\/a><\/div>\n
Learn advanced Linux commands<\/a><\/div>\n
Download cheat sheets<\/a><\/div>\n
Find an open source alternative<\/a><\/div>\n
Explore open source resources<\/a><\/div>\n<\/p><\/div>\n<\/p><\/div>\n

Compute node governance<\/h2>\n

Compute node governance is suitable for cluster mode. For more information about the ShardingSphere modes, please see Your detailed guide to Apache ShardingSphere’s operating modes<\/a>.<\/p>\n

Cluster preparation<\/h2>\n

Take a standalone simulation of three proxy compute nodes as an example. To use the mode, follow the configuration below:<\/p>\n

\n
mode:
\ntype: Cluster
\nrepository:
\ntype: ZooKeeper
\nprops:
\nnamespace: governance_ds
\nserver-lists: localhost:2181<\/span>
\nretryIntervalMilliseconds: 500<\/span>
\ntimeToLiveSeconds: 60<\/span>
\nmaxRetries: 3<\/span>
\noperationTimeoutMilliseconds: 500<\/span>
\noverwrite: false<\/span><\/div><\/div><\/pre>\n
Execute the bootup<\/code> command separately:<\/p>\n
\n
sh<\/span> %<\/span>SHARDINGSPHERE_PROXY_HOME%\/<\/span>bin\/<\/span>start.sh 3307<\/span>
sh<\/span> %<\/span>SHARDINGSPHERE_PROXY_HOME%\/<\/span>bin\/<\/span>start.sh 3308<\/span>
sh<\/span> %<\/span>SHARDINGSPHERE_PROXY_HOME%\/<\/span>bin\/<\/span>start.sh 3309<\/span><\/div><\/div><\/pre>\n
After the three proxy instances are successfully started, the compute node cluster is ready.<\/p>\n
SHOW INSTANCE LIST<\/h4>\n
Use the client to connect to any compute node, such as 3307:<\/p>\n
\nmysql -h<\/span> 127.0.0.1 -P<\/span> 3307<\/span> -u<\/span> root -p<\/span><\/code><\/span><\/pre>\n
View the list of instances using SHOW INSTANCE LIST<\/code>:<\/p>\n
\n
mysql><\/span> SHOW<\/span> INSTANCE LIST;
+<\/span>----------------+-----------+------+---------+<\/span>
|<\/span> instance_id \u00a0 \u00a0|<\/span> host \u00a0 \u00a0 \u00a0|<\/span> port |<\/span> STATUS<\/span> \u00a0|<\/span>
+<\/span>----------------+-----------+------+---------+<\/span>
|<\/span> 10.<\/span>7.<\/span>5.<\/span>35@3309 |<\/span> 10.<\/span>7.<\/span>5.<\/span>35 |<\/span> 3309<\/span> |<\/span> enabled |<\/span>
|<\/span> 10.<\/span>7.<\/span>5.<\/span>35@3308 |<\/span> 10.<\/span>7.<\/span>5.<\/span>35 |<\/span> 3308<\/span> |<\/span> enabled |<\/span>
|<\/span> 10.<\/span>7.<\/span>5.<\/span>35@3307 |<\/span> 10.<\/span>7.<\/span>5.<\/span>35 |<\/span> 3307<\/span> |<\/span> enabled |<\/span>
+<\/span>----------------+-----------+------+---------+<\/span><\/div><\/div><\/pre>\n
The above fields mean:<\/p>\n