Error response from daemon: Conflict. The container name "/hadoop-c" is already in use by container

[political science <ta...@gmail.com>]

Hi,
I have had a hadoop installation from sources. I had started the container
named hadoop-c I rebooted the machine and after a couple of days I came
back to same virtual machine and do

docker run -dit --name=hadoop-c hadoop-build-1001
so I get

docker: Error response from daemon: Conflict. The container name
"/hadoop-c" is already in use by container
"174509213b303b984e6f09cce99487301f1ffb177ddb08091b6e94ca7e10e20b". You
have to remove (or rename) that container to be able to reuse that name.
See 'docker run --help'.

I wanted to do know that after a shutdown does the container still remains
active on next boot always or this is the expected thing.
I am not very familiar with hadoop and dockers etc.
What should I do?.


Also I have one more question
I installed Hadoop on a Ubuntu 19.10  virtual machine. I downloaded the
source file that means among the releases available on this page
https://hadoop.apache.org/releases.html I downloaded 3.1.3 file
https://www.apache.org/dyn/closer.cgi/hadoop/common/hadoop-3.1.3/hadoop-3.1.3-src.tar.gz
the installation was successful. I got the following message
It appears that I have low memory.
image https://i.stack.imgur.com/Qwke9.jpg
I have allotted 2 GB of memory for this virtual machine of Ubuntu. If you
can see in the  screenshot there are many more virtual machines which I
intend to use.
https://i.stack.imgur.com/7yi3M.jpg

I need other virtual machines for various development works. I want to know
how should or rather in what range I should increase the memory so that I
can work with Hadoop ecosystem on ubuntu 19.10. I plan to do some
development work which can be done with single nodes later on I want to
work with multiple nodes. I am doing all this on my laptop which has 12 GB
RAM. and I have following virtual machines
1)Ubuntu 19.10 VM
2)Debian 10 VM

4)Cloudera Hadoop VM
5)Ubuntu 19.10 (I have installed Hadoop in this VM)

I have given 2 GB to all VMs.

I also want to know as seen in above I get a Hadoop command prompt. How can
I again get it I mean if I power off the machine. I notice the shell in
above images as debian@4d943db32085:~/hadoop$

debian is my username configured in Ubuntu 19.10 I want to know what is
this kind of shell that I got above and why is this number
debian@4d943db32085 coming

What could be a problem due to which I am getting a low memory message?

What should I check?



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