1st Error: after following all the steps in the first and second page of the above tutorial the next step was to start SSH
but I got error.
[root@fedora ~]# systemctl start ssh
Failed to start ssh.service: Unit ssh.service not found.
(so I searched about it and tried installing it using this command
sudo dnf install openssh-server
it returned ’ ’ ’ already installed ’ ’ ’
— systemctl start sshd
this one ran, but did not give any results.
All these commands threw errors, I dont’t know what should I do next.
Please somebody help me with this.
Somehow I was able to get
test connection
[kirkyagami@fedora ~]$ ssh 127.0.01 kirkyagami@127.0.0.1’s password:
Last login: Sat Jun 25 00:42:37 2022 from 127.0.0.1
Well, systemctl start sshd is the correct way to start the ssh daemon, and that along with the key generation commands allowed you to succeed with ssh 127.0.0.1. Perhaps this isn’t obvious to you, but the effect of ssh 127.0.0.1 is that you are able to connect from your system to itself (127.0.0.1 is your system’s internal IP address) and run commands at the shell (terminal console). You can run the same commands just opening a terminal console, skipping ssh. The purpose of that step in your installation exercise is probably to verify ssh connectivity as the Hadoop infrastructure is normally on a cluster, not one system, and ssh would be used to connect to systems in the cluster.
Now for your step 11, formatting the HDFS, what happens when you run that command?
[kirkyagami@fedora ~]$ hdfs namenode -format
Unknown command: namenode
Usage: hdfs COMMAND
The flags available are a subset of the POSIX ones, but should behave similarly.
Valid commands:
ls [-lah] [FILE]…
rm [-rf] FILE…
mv [-nT] SOURCE… DEST
mkdir [-p] FILE…
touch [-c] FILE…
chmod [-R] OCTAL-MODE FILE…
chown [-R] OWNER[:GROUP] FILE…
cat SOURCE…
head [-n LINES | -c BYTES] SOURCE…
tail [-n LINES | -c BYTES] SOURCE…
du [-sh] FILE…
checksum FILE…
get SOURCE [DEST]
getmerge SOURCE DEST
put SOURCE DEST
df [-h]
I took a quick look at the tutorial you have been using, and I believe there are some formatting issues in the earlier steps that could be impacting your installation. According to the Apache documentation for the hdfs command, namenode is a valid subcommand, but as your results show, it is not accepted.
This forum is focused on Fedora, so unless someone in this community is familiar with installing Hadoop and can guide you, I think you’ll have to go back to the author of the tutorial.
(By “formatting issues” I refer to the display of many of the files you are directed to edit in the tutorial where line breaks are not kept intact.)
Good luck
