markdown/bestpractices/config_hawq_bestpractices.html.md.erb

---
title: Best Practices for Configuring HAWQ Parameters
---

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HAWQ configuration parameters are maintained in the `$GPHOME/etc/hawq-site.xml` file. This file resides on all HAWQ instances and is modified either via Ambari or when using the HAWQ command line interface `hawq config` command. Use a consistent strategy (Ambari or command line) to maintain the contents of `hawq-site.xml`. 

For Ambari-managed clusters, always use Ambari for configuring `hawq-site.xml` parameters; restarting or reconfiguring HAWQ via Ambari will overwrite any configuration changes to `hawq-site.xml` made outside of the Ambari interface. If you cannot tolerate cluster downtime when updating HAWQ configuration parameters, refer to [Updating HAWQ Configuration Without Cluster Restart](../admin/ambari-admin.html#manual-cfg-norestart) for a specific procedure for Ambari-managed clusters.

If you manage your cluster using command line tools instead of Ambari, use a consistent `hawq-site.xml` file to configure your entire cluster. 

**Note:** Do not use the `postgresql.conf` file to configure HAWQ configuration parameters; HAWQ uses only `hawq-site.xml` for this purpose.