Mariadb Galera Cluster Support?

Hello Duane,

UseResponse could be installed using only MYSQL

I know that it can be installed using only mysql but does the UseResponse database meet the Galera Cluster requirements? I would like to install in a Galera Cluster to offer redundancy for the database. For example, it is recommended that application that run on a Galera Cluster have primary keys for every table. There are other requirements specified in the link provided above.

If the database does not support Galera, can you clarify which requirements it does not meet?

As it works only with innodb storage table, our solution won't meet the requirements.

We've never tested it with Galera Cluster, as an option you can make daily backups and clustering won't be required. Even big customers of ours doesn't have any issues

innodb storage tables are actually required for Galera so you do meet that requirement. Can you please look through the other requirements to see if there are any differences between the requirements and your implementation. The requirements are minimal.

As a note, Galera is not for backups (these should be done regardless) but rather from HA. Unfortunately sticking a load balancer in front of several databases does not work because the databases need to be syncronized. Your other clients may be using other forms of MySql clustering but Galera is not only easier but also provides master/master replication by design.

In the system itself there shouldn't be any issues, but in tools, rebuilding indexes won't work and step to backup db while upgrade also won't work.

Everything else should work fine

When do indexes need to be rebuilt?

Also, what do you mean by "step to backup db while upgrade"?

Indexes need to rebuild very rarely when they are corrupted in db.

When you upgrade system to the latest version, first step is to backup db. Most likely it would fail

So I still will be doing regular backups via mysqldump. In the rare case that the indexes become corrupt, can I import the database (from a .sql file) in mysql (no galera cluster), repair the indexes, export the database (via mysqldump), and reinitialize a galera cluster? I assume yes but not sure if there is some gotcha with importing a database with corrupted indexes.

For upgrading, is it possible to manually backup the database thereby skipping the first step?

With indexes, yes - you would be able import it and then repair indexes.

With backups while upgrade, we don't have option to skip first step unless its commented in the code directly, but we'll consider this option

Has there been any progress to fully supporting a Galera cluster for all UseResponse functionality?

Hi Duane,

We still require first step to backup the db while upgrading the system to the latest version which means there is no full support of Galera cluster.

Is the rebuilding the indexes issues resolved?

Why will the backup fail with a galera cluster?

Hello Duane,

As it works only with the InnoDB storage engine, our solution won't meet the requirements.

We support only the MyISAM engine.

Galera cluster depends on InnoDB. It is not a substitute for InnoDB. MyISAM is a different storage engine so I don't understand your comment. Please verify based on the above and advise.

UseResponse DB doesn't support Galera as it doesn't work with InnoDB engine.

That is not true. Please see Stas' comment above. Also, I have UseResponse running on innodb without issue.

UseResponse supports only MySQL or MariaDB database and uses the MyISAM table engine.

As we informed you earlier, we've never tested our service with Galera Cluster. So, if Galera Cluster does not break the default database behavior, then this will likely work. But we can't guarantee the operability of our application.

I apologize. You are correct. After reviewing the mysql tables from a dump, I notice the MyISAM engine. While UseResponse may have appeared to have worked with galera, it will likely break functionality with the app.

I appreciate you support.

You are welcome!

I'm glad that we've sorted out your question.

Best regards,

Liza