List the namenode and datanodes of a cluster from any node?

Question

From any node in a Hadoop cluster, what is the command to

I have looked through the commands manual and have not found this.

List of datanodes is available via namenode's JMX interface -- https://stackoverflow.com/q/44069584/1097572 — sendmoreinfo, Jan 28 '19 at 20:22

Tejas Patil · Accepted Answer · 2016-04-09T07:17:53.463

57

bin/hadoop dfsadmin -report

Update (2015):

bin/hdfs dfsadmin -report

edited Apr 09 '16 at 07:17

answered Jun 01 '13 at 03:40

Tejas Patil

2

OK what I don't get is why my namenode only reports itself as a datanode, and none of the datanodes I listed in `slaves` file show up in `dfsadmin -report` – T. Webster Jun 01 '13 at 03:45
On the namenode url (http://:50070/dfshealth.jsp), see if the other nodes are dead / decomissioned. Also, watch the datanode logs to identify the problem – Tejas Patil Jun 01 '13 at 03:56
4

This command is now deprecated: `DEPRECATED: Use of this script to execute hdfs command is deprecated.` – CDT Jul 31 '15 at 03:32

score 35 · Answer 2 · edited May 14 '19 at 12:42

35

Try this:

hdfs getconf -namenodes
hdfs getconf -secondaryNamenodes

edited May 14 '19 at 12:42

ttimasdf

answered Mar 22 '16 at 14:19

Vishwanath

score 26 · Answer 3 · answered Oct 19 '16 at 17:08

26

Try This. For dfsadmin not every user has permission.

hdfs getconf -confKey fs.defaultFS
hdfs://XYZ

answered Oct 19 '16 at 17:08

shashaDenovo

gsamaras · Answer 4 · 2017-01-02T15:31:44.147

5

2016 update, following Tejas answer:

hadoopuser@gsamaras:~/hadoop/bin$ ./hdfs dfsadmin -report

edited Jan 02 '17 at 15:31

answered Jan 24 '16 at 14:07

gsamaras

score 0 · Answer 5 · answered Jul 05 '23 at 07:38

hdfs getconf -namenodes
hdfs getconf -secondaryNamenodes

Work only non-HA mode. The simplest way for HA-mode is to use:

hdfs haadmin -getAllServiceState

haadmin work for HA mode.

Output:

hadoop-adh-1:8020                standby
hadoop-adh-2:8020                active

5 Answers5