1. First Install CUPS

yum install cups

2. Service Start and Stops 

systemctl enable cups
systemctl start cups 

3. Edit the Configuration file

sudo nano /etc/cups/cupsd.conf

Listen localhost:631

to

Listen *:631

grep -v '#' /etc/cups/cupsd.conf 

Managing temporary files with systemd-tmpfiles on Red Hat

Why the files in /tmp directory gets deleted periodically

For CentOS/RHEL7

cd /usr/lib/tmpfiles.d/tmp.conf

# cat /usr/lib/tmpfiles.d/tmp.conf
# Clear tmp directories separately, to make them easier to override
v /tmp 1777 root root 10d
v /var/tmp 1777 root root 30d

# Exclude namespace mountpoints created with PrivateTmp=yes
x /tmp/systemd-private-%b-*
X /tmp/systemd-private-%b-*/tmp
x /var/tmp/systemd-private-%b-*
X /var/tmp/systemd-private-%b-*/tmp

For CentOS/RHEL6

cd /etc/cron.daily/tmpwatch

# cat /etc/cron.daily/tmpwatch
#! /bin/sh
flags=-umc
/usr/sbin/tmpwatch "$flags" -x /tmp/.X11-unix -x /tmp/.XIM-unix \
	-x /tmp/.font-unix -x /tmp/.ICE-unix -x /tmp/.Test-unix \
	-X '/tmp/hsperfdata_*' -X '/tmp/.hdb*lock' -X '/tmp/.sapstartsrv*.log' \
	-X '/tmp/pymp-*' 10d /tmp

# man tmpwatch 

 Using Ubuntu Software Center

 Depends on Country wise but typical Indian govt also used ubuntu OS

Here is the offically website of ubuntu you can find more about it

https://ubuntu.com/gov

 No,

Better to go with DVD which start from 4.7GB

1. CD 700MB to 1.4GB

2. DVDs 4.7GB to 9.4GB, and 

3. BluRay Discs 25GB to 50GB

 Requirment 

1. docker should be installed

2. docker-compose also be installed

Installation of docker

1.  sudo apt-get install docker.io or sudo apt  install docker.io

2. docker --version

3. sudo apt-get install docker-compose

Creating a Configuration files of prometheus

1. create a new file prometheus.yml and copy paste below

sudo nano ~/ prometheus.yml  or sudo nano /etc/prometheus/prometheus.yml

# prometheus.yml
global:
 scrape_interval: 5s
 external_labels:
   monitor: 'my-monitor'
rule_files:
 - 'alert.rules'
scrape_configs:
 - job_name: 'prometheus'
   static_configs:
     - targets: ['your_server_ip:9090']

2. create a new file docker-compose.yml and copy paste below

sudo nano ~/docker-compose.yml or sudo nano /etc/prometheus/docker-compose.yml

# docker-compose.yml
version: '2'
services:
  prometheus:
     image: prom/prometheus:latest
     volumes:
       - ./prometheus.yml:/etc/prometheus/prometheus.yml            
     command:
       - '--config.file=/etc/prometheus/prometheus.yml'
     ports:
       - '9090:9090'

 3. Run the docker compose file

cd /etc/prometheus/ or sudo ~/docker-compose up

sudo docker-compose up

 4. Open browser

http://your_server_ip:9090

 5. Install Node exporter

node-exporter:
     image: prom/node-exporter
     ports:
       - '9100:9100'

- job_name: 'node-exporter'
   static_configs:
     - targets: ['node-exporter:9100'] 

 6. Restart docker-composer

cd /etc/prometheus/ or sudo ~/docker-compose restart

sudo docker-compose restart

7. Install Grafana

sudo nano ~/docker-compose.yml or sudo nano /etc/prometheus/docker-compose.yml

copy paste at last line  

grafana:
     image: grafana/grafana
     user: "0" #[ Execute  id -u in terminal to find the user id from where you are invoking docker compose]
     volumes:
       - ./grafana_db:/var/lib/grafana
     environment:
       - GF_SECURITY_ADMIN_PASSWORD=yourpass
     depends_on:
       - prometheus
     ports:
       - '3000:3000'

 4. Open browser

http://your_server_ip:3000

1. Create a new file 

sudo nano ~/prometheus.yml

 Add below lines or copy paste into prometheus file

# A scrape configuration scraping a Node Exporter and the Prometheus server
# itself.
scrape_configs:
  # Scrape Prometheus itself every 5 seconds.
  - job_name: 'prometheus'
    scrape_interval: 5s
    static_configs:
      - targets: ['localhost:9090']

  # Scrape the Node Exporter every 5 seconds.
  - job_name: 'node'
    scrape_interval: 5s
    static_configs:
      - targets: ['your_server_ip:9100']
 

2. docker run -d -p 9090:9090 -v ~/prometheus.yml:/etc/prometheus/prometheus.yml prom/prometheus --config.file=/etc/prometheus/prometheus.yml --storage.tsdb.path=/prometheus

3. docker ps

4. http://your_server_ip:9090/status

ERROR :- state : UNKNOWN

SOLUTION :- remove  -storage.local.memory-chunks=10000