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Learn how to configure settings in HCL Launch elements and communication between the elements.
Releasing VC LOB space
After you upgrade to HCL Launch 7.0.5 and later, you can compress the amount of large object (LOB) storage space that HCL Launch uses in the vc_persistent_record database table.
Releasing LOB space in MySQL or Maria databases
You can release the large object (LOB) storage in the MySQL or Maria databases.

Administering
Learn how to configure settings in HCL Launch elements and communication between the elements.
- High availability and failover
  You can configure clustered HCL Launch servers, blueprint design servers, and agents for high availability. You can also configure agents and agent relays for failover.
- Setting up high-availability clusters
  To configure a high-availability cluster, you store shared files on network storage. Then, you configure multiple servers, set each server to access the same files and database, and configure a load balancer to distribute the traffic between the servers.
- Configuring agents for failover
  To configure agents for failover, you specify two or more target servers for the agent to use. If one of the servers fails, the agent switches to another server from the list.
- Configuring agent relays for failover
  To configure agent relays for failover, you specify two or more target servers for the agent relay to use. If one of the servers fails, the agent relay switches to another server from the list.
- Server settings and configuration
  After you install HCL Launch, you can modify the server configuration and configure more options.
- Setting user preferences
  Each user can specify display options for the server, including the language for the server and how the server shows times and dates.
- Agents and agent relay configuration
  After you install an agent for HCL Launch, you can modify its configuration or create an agent relay to facilitate communication to remote relays.
- License management
  HCL Launch provides a 60-day license-free evaluation period. To use all product features after the evaluation period, you must have a license.
- Setting up the wizard for new users
  HCL Launch includes a wizard to help users become familiar with the procedures and steps in creating a deployment. Some configuration is required before the wizard can be used.
- Customizing the table views
  Customize a table view in the HCL Launch application by hiding or showing, and reordering of the table columns.
- Releasing VC LOB space
  After you upgrade to HCL Launch 7.0.5 and later, you can compress the amount of large object (LOB) storage space that HCL Launch uses in the vc_persistent_record database table.
  - Releasing LOB space in Oracle databases
    You can release the large object (LOB) storage in the Oracle databases.
  - Releasing LOB space in MySQL or Maria databases
    You can release the large object (LOB) storage in the MySQL or Maria databases.
  - Releasing LOB space in Microsoft SQL Server databases
    You can release the large object (LOB) storage in the Microsoft SQL Server database.
  - Releasing LOB space in DB2 databases
    You can release the large object (LOB) storage in the DB2 database.

Releasing LOB space in MySQL or Maria databases

You can release the large object (LOB) storage in the MySQL or Maria databases.

Before you begin

Consider the following points when you plan an upgrade:

You might be able to avoid the downtime by running the alter table statement before you upgrade:
```
alter table vc_persistent_record modify persistent_data longtext null, add compessed_data longblob null, lock=none
```
If this command fails, an online change of the table before upgrade isn't possible with your version of MySQL. Downtime is required during the upgrade.
Based on the MySQL version you are using, the upgrade or pre-upgrade table change temporarily uses additional space to rebuild the table.
For bext results, run the statement on a table clone to estimate the upgrade time.
Use the alter table command only if the table does not include a compressed_data column.

About this task

Release LOB storage for MySQL and Maria databases using the following steps:

Procedure

Set the experimental.vcUpgrade.enabled=true property in the conf/server/installed.properties file.
Restart the HCL Launch server.
Check on the progress of the conversion:
```
select count(*) from vc_persistent_record where persistent_data is not null
```
The compression process is complete when the row count reported by the query is 0.

Check the database size:

select table_schema, sum((data_length+index_length)/1024/1024) AS MB from information_schema.tables group by 1

Compress the database table.
- Use the optimize statement for MySQL v5.6 and later, and MariaDB v10.0 and later:
```
optimize table vc_persistent_record
```
  See the MySQL documentation about using the optimizing statement: https://dev.mysql.com/doc/refman/5.7/en/optimize-table.html.
- For all other versions of MySQL, complete these steps:
  1. Backup your database:
```
mysqldump -h hostname -u username -p password --databases dbname > ~/mysql-backup.sql
```
  2. Create a new database and restore the old database:
```
mysql -h hostname -u username -p password < mysql-backup.sql
```
  Note: The backup and restore must be done when the system is offline to prevent loss of new data while restoring.

What to do next

Verify that the space is reduced:

select table_schema, sum((data_length+index_length)/1024/1024) AS MB from information_schema.tables group by 1

Set the experimental.vcUpgrade.enabled parameter back to false in the conf/server/installed.properties file.