Upgrading DLM

There are multiple components and clusters that are involved while upgrading DLM.

Dataplane Platform and DLM App which are installed on the Dataplane host.
HDP and DLM Engine on the multiple HDP clusters.
Before performing the DLM upgrade make a copy of /usr/dlm/current/beacon/conf directly.

Post-upgrade, make sure all the manual changes that were performed previously must be repeated. You can refer the older configurations from the backup directory.

	Note
	On upgrading HDP version from 2.6.5 to 3.x, DLM Engine would be removed as part of upgrade process. You must install the required version of DLM Engine once the HDP upgrade succeeds.

	Important
	After upgrading from DLM 1.4.x to 1.5.x on a secure cluster, if the Knox gateway is not installed on the cluster, you must set `beacon.kerberos.authentication.enabled` as `false`.

	Caution
	Hive replication from DLM 1.4.x/HDP 2.6.5 to DLM 1.5.x/HDP 3.1 is not possible. You must upgrade DLM on source from 1.4.x to 1.5.x to proceed with this scenario.

These components and clusters may not be upgraded at once, but can be upgraded over a period of time. DLM is designed to work across versions for these components.

However, the following upgrade order is recommended for performing the upgrade process.

Upgrade Dataplane Platform and DLM App on the Dataplane host.
Upgrade HDP and DLM Engine on one cluster
Upgrade HDP and DLM Engine on another cluster