This is similar to Setup New Liux (Physical) Box
This page goes through the various settings that take place to setup a new Ubuntu VM. In this case I was setting Ubuntu 20.10 Groovy Gorilla.
Specific steps for Debian/Bookworm
In the past (Debian Buster) you will have to update /etc/apt/sources.list by adding contrib non-free to the end of line. However, this time around, this file was empty! Below are the lines obtained from Debian sources list. Also added non-free-firmware to the end.
deb http://deb.debian.org/debian bookworm main contrib non-free non-free-firmware deb-src http://deb.debian.org/debian bookworm main contrib non-free non-free-firmware deb http://deb.debian.org/debian-security/ bookworm-security main contrib non-free non-free-firmware deb-src http://deb.debian.org/debian-security/ bookworm-security main contrib non-free non-free-firmware deb http://deb.debian.org/debian bookworm-updates main contrib non-free non-free-firmware deb-src http://deb.debian.org/debian bookworm-updates main contrib non-free non-free-firmware
apt update apt-get install aptitude aptitude install vim sudo sysstat locate postfix ssl-cert bsd-mailx net-tools zip unzip rsync git screen ln -s /usr/sbin/ifconfig /usr/local/bin/ifconfig updatedb
Optional packages to install
aptitude install ncdu htop nload pydf iotop
Use tasksel to install GUI such as KDE Plasma.
set mouse=echo "set mouse=" > ~/.vimrc sudo echo "set mouse=" | sudo tee -a /root/.vimrc
When cloning, make sure to update the root password on the clone. Debian requires it when you need to rescue the system.
Update /etc/ssh/sshd_config to include
PermitRootLogin prohibit-password PermitEmptyPasswords no TCPKeepAlive yes
To temporarily enable Root Login
PermitRootLogin yes
Specify the Static IP address and DNS address in /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
source /etc/network/interfaces.d/*
# The loopback network interface
auto lo
iface lo inet loopback
# The primary network interface
allow-hotplug enp0s3
#iface enp0s3 inet dhcp
auto enp0s3
iface enp0s3 inet static
address 192.168.1.47
netmask 255.255.255.0
network 192.168.1.0
gateway 192.168.1.1
broadcast 192.168.1.255
dns-nameservers 192.168.1.48
dns-nameservers 192.168.1.10
dns-nameservers 192.168.1.1
dns-nameservers 8.8.8.8
# This is an autoconfigured IPv6 interface
#iface enp0s3 inet6 auto
#
# The network interface for Host-Only Network
auto enp0s8
iface enp0s8 inet static
address 192.168.56.47
netmask 255.255.255.0
network 192.168.56.0
gateway 192.168.56.1
broadcast 192.168.56.255
Update /etc/resolv.conf as well to indicate the DNS entries and DNS configuration
nameserver 192.168.1.48 nameserver 192.168.1.10 nameserver 192.168.1.1 nameserver 8.8.8.8 options timeout:1 options attempts:1
Include the new server in the DNS entries on the DNS servers: ubv47 and ubv10.
Add the entry in /etc/hosts.dnsmasq as below:
192.168.1.50 server50 server50.example.org
Restart dnsmasq
systemctl restart dnsmasq
# OR
service dnsmasq restart
Add new server in Backuppc (ubv33) /etc/hosts. Then copy SSH keys to be able to log in as root from backuppc user.
ssh-copy-id root@<new server>
Below is the list of Nagios configurations
aptitude install nagios-nrpe-server # On /etc/nagios/nrpe.cfg, update line to ''allowed_hosts=127.0.0.1,::1,192.168.1.0/24'' # Copy /etc/nagios/nrpe.d/cu_nrpe.cfg configuration from an existing server # Copy the following files from another server to ''/usr/lib/nagios/plugins/''. # check_deleted_lsof # check_cpu.sh # check_uptime # check_template # check_mem.pl # check_lost_found # check_log1 # check_file_per # check_mailq # Make nagios user part of sudo group systemctl restart nagios-nrpe-server
Update file /etc/nagios/nrpe.cfg and change line as below
allowed_hosts=127.0.0.1,::1,192.168.1.0/24
Create file /etc/nagios/nrpe.d/cu_nrpe.cfg with the below
command[check_cu_users]=/usr/lib/nagios/plugins/check_users -w 10 -c 15 command[check_cu_load]=/usr/lib/nagios/plugins/check_load -w 15,10,5 -c 20,15,10 command[check_cu_zombie_procs]=/usr/lib/nagios/plugins/check_procs -w 1 -c 2 -s Z command[check_cu_total_procs]=/usr/lib/nagios/plugins/check_procs -w 150 -c 200 command[check_cu_swap]=/usr/lib/nagios/plugins/check_swap -w 20 -c 10 command[check_cu_mailq]=/usr/lib/nagios/plugins/check_mailq -w 1 -c 5 -M postfix command[check_cu_ntp_time]=/usr/lib/nagios/plugins/check_ntp_time -H pool.ntp.org -w 30 -c 60 command[check_cu_memory]=/usr/lib/nagios/plugins/check_mem.pl -u -C -w 80 -c 90 command[check_cu_raid]=/usr/lib/nagios/plugins/check_raid command[check_cu_cron]=/usr/lib/nagios/plugins/check_procs -w 1:1 -c 1:1024 -C cron command[check_cu_pcpu]=/usr/lib/nagios/plugins/check_procs -w 40 -c 45 --metric=CPU -v command[check_cu_fp_tmp]=/usr/lib/nagios/plugins/check_file_per -f /tmp -p 1777 command[check_cu_disk]=/usr/lib/nagios/plugins/check_disk -w 15% -c 10% -N ext4 -f command[check_cu_uptime]=/usr/lib/nagios/plugins/check_uptime --warning 60: --critical 60: command[check_cu_cpu]=/usr/lib/nagios/plugins/check_cpu.sh -w 90 -c 95 command[check_cu_lostfound]=/usr/bin/sudo /usr/lib/nagios/plugins/check_lost_found -w 1 -c 2 command[check_cu_kernlog]=/usr/bin/sudo /usr/lib/nagios/plugins/check_log1 -F /var/log/kern.log -O /tmp/kern.log -q ^ command[check_cu_deleted_lsof]=/usr/bin/sudo /usr/lib/nagios/plugins/check_deleted_lsof -w 50000000 -c 60000000
Add nagios to sudo group to execute commands that need root access
usermod -a -G sudo nagios
Copy /home/senthil/tools directory to the new server
Validate Postfix configuration
date|md5summysql_secure_installation to make db secure./etc/aliases to includeroot: system@example.org user: system@example.org
Then run newaliases