To ensure that a multi-node cluster remains available, configure and enable High
Availability. The configuration process for High Availability includes defining locations and
names of hosts in a cluster that are available to act as journal nodes, and a standby name
node in the event that the primary name node fails. To configure name node High Availability,
select the HA components tab. Define the locations and names of hosts in a
cluster that are available to act as JournalNodes and the Resource Manager. Specify a standby
name node in case the primary name node fails.
To enable High Availability, you must also run several commands while starting cluster services.
Table 2.5. High Availability configuration property information
|
Configuration Property Name |
Description |
Example Value |
Mandatory/Optional |
|---|---|---|---|
|
Enable HA |
Whether to deploy a highly available NameNode or not. |
yes or no |
Optional |
|
NN Journal Node Hosts |
A comma-separated list of FQDN for cluster nodes that will run the JournalNode processes. |
journalnode1.acme.com, journalnode2.acme.com, journalnode3.acme.com |
Optional |
|
NN HA Cluster Name |
This name is used for both configuration and authority component of absolute HDFS paths in the cluster. |
hdp2-ha |
Optional |
|
NN Journal Node Edits Directory |
This is the absolute path on the JournalNode machines where the edits and other local state used by the JournalNodes (JNs) are stored. You can only use a single path for this configuration. |
d:\hadoop\journal |
Optional |
|
NN Standby Host |
The host for the standby NameNode. |
STANDBY_NAMENODE. acme.com |
Optional |
|
RM HA Cluster Name |
A logical name for the Resource Manager cluster. |
HA Resource Manager |
Optional |
|
RM Standby Host |
The FQDN of the standby resource manager host. |
rm-standby-host.acme.com |
Optional |
|
Enable Knox HA |
Enable Knox High Availability mode |
Selected |
Optional |
|
Enable Oozie HA |
Enable Oozie High Availability mode |
Selected |
Optional |
|
Oozie server hosts |
A comma-separated list of FQDN for cluster nodes that will run Oozie servers. |
ooziehost1.acme.com, ooziehost2.acme.com |
Optional |
|
Oozie load balancer URL |
URL for Oozie Load Balancer |
http://oozie.lb.com:11000/oozie |
Optional |
