== Machine Setup ==

==== 1.  Install Ubuntu or Debian - prefer the server version of your chosen Ubuntu or Debian LTS distro ====

==== 2.  Change root password ====
{{{
cslab@machine:~$ sudo su
root@machine:~# passwd
}}}

==== 3.  Update and install necessary packages ===
{{{
root@machine:~# apt update
root@machine:~# apt upgrade -y && apt install -y vim git htop dstat nfs-common nis tmux
root@machine:~# apt autoremove -y
}}}

==== 4.  Remove swap ====
{{{
root@machine:~# swapoff -a
root@machine:~# rm -v /swap.img
}}}

==== 5.  Connect the NFS (nemesis is down (3.3), comment it out) ====
{{{
root@machine:~# vim /etc/fstab: 
		# swap -> comment-out
		147.102.4.1:/home	/home	nfs	defaults	0	0
		147.102.4.1:/various	/various	nfs	defaults,nolock	0	0
		#147.102.3.3:/store/cluster_data	/risky_store	nfs	nfsvers=3,nolock	0	0
}}}

==== 6. NIS setup ====

* Determine users, passwords, groups
{{{
root@machine:~# vim /etc/nsswitch.conf
		at passwd, group, shadow add: files nis
}}}

* Create defaultdomain file

{{{
root@machine:~# vim /etc/defaultdomain
               write: sci.nis
}}}

* Set ypserver

{{{
root@machine:~# vim /etc/yp.conf
   at ypserver line, write:
   ypserver scirouter.cslab.ece.ntua.gr
}}}

* Enable the service:

{{{
root@machine:~# systemctl enable ypbind.service
}}}

==== 7.  Test if the previous step was successful====
{{{
root@machine:~# yptest (must read the config)
root@machine:~# id ypap (must return user)
root@machine:~# ps -ef | grep yp (ypbind.service must be running)
}}}
  If not running:
{{{
root@machine:~# systemctl restart ypbind
root@machine:~# systemctl list-unit-files | grep yp
}}}

==== 8.  Remove Password authentication from sshd ====
{{{
root@machine:~# vim /etc/ssh/sshd_config
                PasswordAuthentication no
}}}

==== 9.  Connection fix [NOT NECESSARY] ====
{{{
root@machine:~# vim /lib/systemd/system/systemd-{logind, udevd}.service # comment-out IPAddressDeny=any
root@machine:~# systemctl daemon-reload
root@machine:~# systemctl restart systemctl-logind
root@machine:~# systemctl restart systemctl-udevd
}}}