Understanding the secondary namenode UI
The secondary namenode is a checkpoint service for the namenode daemon that performs periodic merging of the edits
log and the fsimage
file. The secondary namenode UI can be accessed using the following URL:
http://<secondary-namenode-server>:50090/
The following screenshot shows the secondary namenode UI:
Just like the namenode UI, the secondary namenode UI also displays the Hadoop version. All checkpoint related information is available in this UI, which are given as follows:
- Name Node Address: This is the RPC address of the primary namenode daemon. Secondary namenode uses this address to connect to primary namenode.
- Start Time: This is the start timestamp of the secondary namenode service.
- Last Checkpoint Time: This the timestamp of the last checkpoint action performed by the secondary namenode daemon.
- Checkpoint Period: This property defines the schedule to perform the checkpoint. In the preceding screenshot, the value is 3,600 seconds. This...