How to create password less ssh connection for multiple non-root users

I had done password less shh authentication between multiple Linux box a couple of time but this time I had to do the same for normal user. I thought it would be same and actually it is the same but still there are few things which we might miss out and also it becomes a bit complicated and confusing as I did so for them I thought I should give some tips.

Question
You have to create a password less ssh connection between 3 Linux box for non root user i.e a normal user deepak.

Pre-requisites
User deepak should exist on all the 3 Linux box

Server details
server 1
IP 192.168.0.101

server 2
IP 192.168.0.102

server 3
IP 192.168.0.103

Making password less connection from Server 1

On server 1
Login as user deepak
[deepak@server101 ~]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/deepak/.ssh/id_rsa):
Created directory '/home/deepak/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/deepak/.ssh/id_rsa.
Your public key has been saved in /home/deepak/.ssh/id_rsa.pub.
The key fingerprint is:
f8:c3:78:b7:6d:89:01:3e:44:bc:3c:df:70:72:04:0c deepak@server101.example

With the above command we have created a pair of public and private key using RSA type authentication.

Click the link to know more about RSA and DSA type of authentication

Now to create a password less ssh connection we need to copy id_rsa.pub to the remote server i.e server 2 and server 3
[deepak@server101 ~]$ scp .ssh/id_rsa.pub 192.168.0.102:/home/deepak/
[deepak@server101 ~]$ scp .ssh/id_rsa.pub 192.168.0.103:/home/deepak/
On server 2
Create .ssh directory in your home folder as it will not be present by default
NOTE: Make sure the permission on .ssh is 700
[deepak@server102 ~]$ mkdir .ssh
[deepak@server102 ~]$ ls -al | grep .ssh
drwx------ 2 deepak deepak  4096 Jan 10 23:24 .ssh
This next step you are appending the contents of the copied id_rsa.pub from server 1 into your authorized_keys file

NOTE: By default authorized_keys file will not be present. The below command will automatically create this file and append the output of cat into it.
[deepak@server102 ~]$ cat id_rsa.pub >> .ssh/authorized_keys
NOTE: Make sure the permission on authorized_keys is 600
[deepak@server102 ~]$ ls -al .ssh/
-rw------- 1 deepak deepak   1616 Jan 11 04:21 authorized_keys
To view the contents of the contents of copied id_rsa.pub into authorized_keys
[deepak@server102 ~]$ cat .ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAvaI3NDGXRQ922OJBh3nYmjkWwA6m0A7leiciIhXV1NxntM38K2Y8XIvCd3FPruguyB97P2r4mDpHPGtT5X4ZSWP8hrTxVcRmG8PfX0UelkquPikjC3Mj3XbQZC6H7rKLv4qwLR8PayBkdD004NIvhYAbE+5F5UCuDtOdcvoDDfV1pjVq44ZwyZyl1P3oui8GJpTkJ+isI0RASY3HOm50OTy+6XH/5HQLaPkc+0MMtc8D1y1xMqJ26cntsZLzEInuwbVSgUxuzJ/z9+j+Y4f7CJaEDC3fo8YFooQ8VxTdm5aXjeMMYu2mDpTfNn5GIXLCCwhk6kV5M3pdKpF7iPtQ== deepak@server101.example
The same has to be done on server 3

On Server 3
NOTE: Make sure the permission on .ssh is 700
[deepak@server103 ~]$ mkdir .ssh
[deepak@server103 ~]$ ls -al | grep .ssh
drwx------ 2 deepak deepak 4096 Jan 10 23:24 .ssh
[deepak@server103 ~]$ cat id_rsa.pub >> .ssh/authorized_keys
# service sshd restart
Stopping sshd:                                             [  OK  ]
Starting sshd:                                             [  OK  ]
Using the above steps we have successfully created a password less authentication from