Permission Denied error while running start-dfs.sh

Question

I am getting this error while performing start-dfs.sh

Starting namenodes on [localhost] 
pdsh@Gaurav: localhost: rcmd: socket: Permission denied 
Starting datanodes
pdsh@Gaurav: localhost: rcmd: socket: Permission denied
Starting secondary namenodes [Gaurav]
pdsh@Gaurav: Gaurav: rcmd: socket: Permission denied 2017-03-13 09:39:29,559 
WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

Using hadoop 3.0 alpha 2 version.

Any help is appreciated

This might help you http://pka.engr.ccny.cuny.edu/~jmao/node/57 — BruceWayne, Mar 13 '17 at 04:23
Thanks a lot, it took me hours of try and erros. My setup was ubuntu server 22.04 and hadoop 3.3.4. Cheers! — Joni Hoppen, Jan 14 '23 at 17:37

score 68 · Answer 1 · answered Jan 24 '18 at 04:52

68

I also encountered the same thing, I did so I found that my pdsh default rcmd is rsh, not ssh, rsh and ssh remote login authentication is not the same, when installing hadoop I configured ssh localhost password-free login, but rsh is not possible.

so，try：

1.check your pdsh default rcmd rsh

pdsh -q -w localhost

See what your pdsh default rcmd is.

2.Modify pdsh's default rcmd to ssh

export PDSH_RCMD_TYPE=ssh

you can be added to ~/.bashrc, and source ~/.bashrc

3.sbin / start-dfs.sh

answered Jan 24 '18 at 04:52

int32

689
5
3

3

You're great. It definitely worked for me. The people probably set-up it over ssh. But this setting was rsh. This is correct solution. – Erol Erdogan Sep 24 '20 at 19:29
The best resolution on the web so far, Thanks a lot, it took me hours of try and erros. My setup was ubuntu server 22.04 and hadoop 3.3.4. Cheers! – – Joni Hoppen Jan 14 '23 at 17:38
Yes, "connect: Connection refused", big deal. – Wojciech Pawlik Jan 31 '23 at 00:16

score 9 · Answer 2 · answered Mar 05 '20 at 07:44

9

Uninstall pdsh will solve this problem. I am working with Hadoop version 3.2.1 on Ubuntu 18.04.4 LTS.

I test start-dfs.sh on several fresh-installed virtual machines and one old VM. The command failed only on the old VM. I have tried the high-voted answer, and found that only the old VM has pdsh installed. So I uninstall this software, and after that the command executed successfully.

So, if you did not install pdsh for some purpose, you can try to uninstall it.

answered Mar 05 '20 at 07:44

Gary Wang

315
4
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This worked for me too. `pdsh` is not an absolute requirement. From the docs - `Additionally, it is recommmended that pdsh also be installed for better ssh resource management.` – Adi Krishnan Aug 26 '20 at 04:16
after removing pdsh i got ```ERROR: JAVA_HOME is not set and could not be found.``` I don't think it was to be removed. – Lawhatre Oct 15 '21 at 15:22
@Lawhatre `JAVA_HOME` can be explicitly set in `HADOOP_HOME/etc/hadoop/hadoop-env.sh` or `HOME/.bashrc` or `/etc/profile.d/hadoop.sh`. Make sure that JDK/JRE have been installed on your system. – Gary Wang Oct 20 '21 at 01:18

score 8 · Answer 3 · answered Oct 04 '20 at 04:15

8

Try uninstalling pdsh

sudo apt-get remove pdsh

and then restart your hadoop by:

sudo start-dfs.sh

This is what worked for me.

answered Oct 04 '20 at 04:15

Nidhi Raniyer

81
1
1

score 2 · Answer 4 · answered Feb 21 '21 at 10:17

2

A sudo user could also change pdsh's Rcmd type to ssh via the command:

echo "ssh" | sudo tee /etc/pdsh/rcmd_default

answered Feb 21 '21 at 10:17

user15253056

21
1

score 0 · Answer 5 · edited Mar 13 '17 at 17:37

0

Try with sudo

Example:

sudo start-dfs.sh

Otherwise change the owner of the folder hadoop_1.2.7

Example:

sudo chown -R user_name:user_name hadoop_1.2.7

edited Mar 13 '17 at 17:37

JochenJung

7,183
12
64
113

answered Mar 13 '17 at 10:57

Kanagaraj Dhanapal

451
2
10

Hi! thanks for the help... The problem was occurring due to 3.0 alpha 2. When I repeated process in hadoop2.7 it solved the problem... – Gaurav A Dubey Mar 13 '17 at 14:27

Permission Denied error while running start-dfs.sh

5 Answers5