MySQL load balancers becomes a trend setters in Market for High availability and scalability. What can be the best load balancer ? It varies from case to case. This presentation was made at Mydbops meetup on 04-08-2018 covers the basics of load balancers with their advantages and disadvantages.

1. MySQL Load Balancers And It’s Solutions
Mydbops Database Meetup - Aug 2018
Presented by
Vinoth Kanna RS
www.mydbops.com info@mydbops.com

2. About Mydbops
● Founded in 2015, HQ in Bangalore India with 150+ customer base across the globe.
● Mydbops is on Database Consulting with core specialization on MySQL and MongoDB Administration and
Support.
● We have expert team with 20+ certified DBA’s providing full time support and currently managing 300+
servers.
● Mydbops was created with a motto of developing a DevOPS model for Database administration offering
24*7 expert remote DBA support.
● We help organisations to architect and scale systems in MySQL/MongoDB by implementing the advanced
technologies in industry which are completely open source.

3. Mydbops is into MySQL/MongoDB Support and Consulting. It is founded by experts
who have scaled database at Yahoo! ,Percona and Datavail. We are providing an
expert level support and 24*7 monitoring for MySQL databases and its related
technologies like MariaDB , Percona ( also clustering ) . We support modern
database technologies in MySQL which includes Galera ( Clustering ), Group
Replication , SQL aware Load balancers like Maxscale / ProxySQL.
About Mydbops

4. Agenda
● Common MySQL Deployments
● Load balancer Goals
● Maxscale
○ Implementation
○ Applications
● MySQL Router
○ Routing
○ Applications
● ProxySQL
○ Features
○ Monitoring
○ Applications
● References

5. About Mydbops
● Founded in 2015, HQ in Bangalore India with 150+ customer base across the globe.
● Mydbops is on Database Consulting with core specialization on MySQL and MongoDB Administration and
Support.
● We have expert team with 20+ certified DBA’s providing full time support and currently managing 300+
servers.
● Mydbops was created with a motto of developing a DevOPS model for Database administration offering
24*7 expert remote DBA support.
● We help organisations to architect and scale systems in MySQL/MongoDB by implementing the advanced
technologies in industry which are completely open source.

6. About Mydbops
● Founded in 2015, HQ in Bangalore India with 150+ customer base across the globe.
● Mydbops is on Database Consulting with core specialization on MySQL and MongoDB Administration and
Support.
● We have expert team with 20+ certified DBA’s providing full time support and currently managing 300+
servers.
● Mydbops was created with a motto of developing a DevOPS model for Database administration offering
24*7 expert remote DBA support.
● We help organisations to architect and scale systems in MySQL/MongoDB by implementing the advanced
technologies in industry which are completely open source.

7. Common MySQL Deployments
Deployment Models:
● Native MySQL Replication
● Group Replication / InnoDB Cluster
● Galera Replication / MariaDB Cluster / PXC
Traffic Routing:
● No balancing, All requests to Master
● Pointing applications to various nodes
○ Master for read write apps / api’s
○ Own set of slaves for read only apps / api’s
● Haproxy

8. Load balancer Goals
● Simple proxy layer to connect database pools
● Share the traffic across the available pool of servers
● Flexible routing algorithms
● Handle availability, In case of node failures
● Ability to understand, Monitor various MySQL deployment models
● Transparency in routing
● Ability to Gather metrics, Statistics from the proxy layer

9. SQL Aware Balancers

10. Maxscale
● Maxscale is an intelligent load balancer from MariaDB
● Started as a Open Source project, later adopted BSL
● Current version is 2.2.12
● Under BSL, Maximum usage of 3 nodes only allowed for free
Release License Tentative GPL Adoption
v1.4.* GPL -
v2.0.* BSL 1, BSL 1.1 2019-01-01
v2.1.* BSL 1.1 2019-07-01
v2.2.* BSL 1.1 2020-01-01

11. Maxscale - Implementation
● Maxscale has a modular implementation, For simplicity it classified into 3 categories
○ Monitors
○ Filters
○ Routers
● Monitor: [State Detection]
○ MySQL Replication
○ Galera
○ NDB Cluster
○ Aurora

12. Maxscale - Implementation
● Filter: [Transform, Log, Route]
○ Database firewall filter - Can be used to whitelist, Blacklist
○ Query log filter - Used to log queries based
○ Tee filter - Used to mirror the traffic
○ Top filter - Used to profile the queries
● Routers: [Perform Routing]
○ readconnroute - Simply balanced connections across servers
○ readwritesplit - Direct writes to Master, Balance reads across servers
○ schemarouter - Route connections based on DB name across servers
○ binlogrouter - Copies Binlog from master, Allows slaves to replicate from it

13. Maxscale - Applications
Perfect Fit
● Out of box, ReadWrite spliting
● Perfect solution to be used with 3 node
Galera cluster
● Binlog server is one of the most used
feature in Maxscale
● v1.4.5 is still a good choice
● Maxscale is BSL, Is it best to adopt ?
Missing Features
● Group replication, InnoDB Cluster support
● Reconfiguration is not completely online
● User based sharding not possible
● Cannot connect to admin interface
remotely
● Query statistics are not as rich as
ProxySQL
● Not completely Open Source, Not suitable
for rapidly evolving environment

14. MySQL Router
● Successor of MySQL Proxy
● Current GA release is 8.0.12
● First GA release 2.0.2, focussed to simplify accessing MySQL Fabric
○ It’s caches Topology or Shard information by connecting the Fabric node
○ Routes traffic to designated Shard
○ Deprecated, Last release is 2.0.4
● Release 2.1.3, came as a part of InnoDB cluster, can be deployed through MySQL Shell
○ Added features, Bootstrapping (Auto Config) through mysql_innodb_cluster_metadata
○ Concurrent connection limit increased from 500 to 5000
○ Supports Single primary / Multi primary modes

15. MySQL Router - Routing
● Router requires to have two endpoints / ports configured one for read and another for
read-write, If we need to balance reads across secondaries and writes only to primary.
● It’s difficult for application that don’t have read-write split in application
● Release 2.*
Modes: read-write, read-only
(During bootstrap, routing depends on variable group_replication_single_primary_mode)
ON OFF
read-write primary round-robin
read-only round-robin not configured

16. MySQL Router - Routing
● Release 8.0.*
○ Release named after MySQL 8
○ Modes is renamed as Routing Strategy, Is now configurable
■ first-available
■ next-available
■ round-robin
■ round-robin-with-fallback
○ Bootstrapping is improved

17. MySQL Router - Applications
Perfect Fit
● InnoDB cluster
● Applications with Read / Write
segregation
Missing Features
● Support for replication
● Routing statistics
● Transparency / Missing admin interface
● Run time changes not possible
● Missing out possibilities of being a SQL
Aware proxy

18. ProxySQL
● Lightweight and powerful load balancer
● Current GA is v1.4.9
● Project started by René Cannaò, Open source
● v1.4.9 features cluster support. Now proxy is never a SPOF
● Native support for replication
● Following technologies through external scripts / schedulers
○ Galera replication (available on proxysql-tools repo)
○ Group replication
○ NDB cluster
● Most of the config changes are dynamic (Uses SQLite as Persistent Store For Config)

19. ProxySQL - Features
● TTL based query caching
● User, fingerprint, regex based query routing
● Fingerprint / regex based query rewrite
● Regex based query blocking
● Request mirroring is possible
● Sharding based on Schema, User, Queries possible
● Query digest profiles for all the queries are maintained
● Response time of call types are recorded
● Provides extensive stats to troubleshoot and configure efficiently
● PMM provides ProxySQL exporters and Dashboard to visualize stats
● Zero downtime failover, maintenance plans can be achieved by proper configuration

20. ProxySQL - Monitoring

21. ProxySQL - Monitoring

22. ProxySQL - Applications
Perfect Fit
● Large scale deployments
● Galera cluster
● Envs where query change is not possible
● Cache MySQL results efficiently
● Require little effort to integrate auto
reconfiguration of master slave members
during failover
● Reconfiguration can be automated by
using hook scripts with MHA, Orchestrator
Missing Features
● Auto discovery of topology
● Real time query classifier

23. References
● http://www.proxysql.com/compare
● https://mydbops.wordpress.com/2018/02/19/proxysql-series-mysql-replication-read-write-sp
lit-up/
● https://mydbops.wordpress.com/2018/03/15/proxysql-series-seamless-replication-switchove
r-using-mha/
● https://mydbops.wordpress.com/2018/04/13/proxysql-series-mirroring-mysql-queries/
● https://mydbops.wordpress.com/2018/05/28/proxysql-series-handling-resource-expensiveba
d-queries-in-mysql/
● https://mydbops.wordpress.com/2016/07/25/scale-with-maxscale-part-1/
● https://mydbops.wordpress.com/2016/08/29/scale-with-maxscale-part-2/
● https://mydbops.wordpress.com/2017/08/24/scale-with-max-scale-part-3-replication/
● https://mydbops.wordpress.com/2018/02/21/scale-with-maxscale-part-4-amazon-aurora/
● https://mydbops.wordpress.com/2018/01/29/maxscale-data-archiving-with-filters-mq-tee/

24. info@mydbops.com
www.mydbops.com
080-48505683
Contact us

25. Thank You