Before upgrading your OpenMetadata version we strongly recommend backing up the metadata.
The source of truth is stored in the underlying database (MySQL and Postgres supported). During each version upgrade there
is a database migration process that needs to run. It will directly attack your database and update the shape of the
data to the newest OpenMetadata release.
It is important that we backup the data because if we face any unexpected issues during the upgrade process,
you will be able to get back to the previous version without any loss.
{% note %}
You can learn more about how the migration process works [here](/deployment/upgrade/how-does-it-work).
{% /note %}
- To run the backup and restore commands, please make sure that you are always in the latest `openmetadata-ingestion` version to have all the improvements shipped in the CLI.
- Also, make sure you have connectivity between your database (MySQL / PostgreSQL) and the host machine where you will be running the below commands.
**1. Create a Virtual Environment and Install the Backup CLI**
Before running the migrations, it is important to update these parameters to ensure there are no runtime errors.
A safe value would be setting them to 20MB.
**If using MySQL**
You can update it via SQL (note that it will reset after the server restarts):
```sql
SET GLOBAL sort_buffer_size = 20971520
```
To make the configuration persistent, you'd need to navigate to your MySQL Server install directory and update the
`my.ini` or `my.cnf` [files](https://dev.mysql.com/doc/refman/8.0/en/option-files.html) with `sort_buffer_size = 20971520`.
If using RDS, you will need to update your instance's [Parameter Group](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_WorkingWithParamGroups.html)
to include the above change.
**If using Postgres**
You can update it via SQL (not that it will reset after the server restarts):
```sql
SET work_mem = '20MB';
```
To make the configuration persistent, you'll need to update the `postgresql.conf` [file](https://www.postgresql.org/docs/9.3/config-setting.html)
with `work_mem = 20MB`.
If using RDS, you will need to update your instance's [Parameter Group](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_WorkingWithParamGroups.html)
to include the above change.
Note that this value would depend on the size of your `query_entity` table. If you still see `Out of Sort Memory Error`s
during the migration after bumping this value, you can increase them further.
After the migration is finished, you can revert this changes.
