lvm

When i try mount a partition i get error

mount: unknown filesystem type ‘LVM2_member’

This is because the partition is LVM. Got it fixed with

iftop

iftop

iftop show bandwidth usage like top show cpu and memory usage.

To see network usage, run

If you have multiple network interface, you need to specify network interface to monitor, this can be done with -i option

To install on CentOS, run

For installing from source, see Install iftop from source on CentOS

On Ubuntu

To use, run iftop

iftop

monit

See gonit golang replacement for monit

monit is a process monitoring service that monitor services, restart if required.

https://mmonit.com/monit/

Here are monit rules used to monitor apache, php-fpm and MySQL on bitnami cloud server.

Mail

Open Source Mail Suits

Complete Mail Server

These software once installed will provide complete mail server including web mail.

Business Email

Free Email Forwarding

Webmail

Email Marketing

To install mail command.

on Debian, run

on CentOS

To send a test email, run

To specify sender address, use -r option

vnstat

vnstat command shows bandwidth usage on your system.

Bandwidth usage by day

ip

Track IP location

http://www.ip-tracker.org

To see network interface cards on your computer, run “ip link”

CentOS

Configure Munin Node

To install munin node on Ubuntu/Debian, run

To configure, edit file

Find

Below this line, you need to add IP of your Munin Master. You need to convert IP to regular expression format before adding. For example, if your IP is 88.212.32.35, you need to add

If you want to allow from any IP, add

Now restart Munin node

Add Node to Munin Master

You need to tell your Munin master about the new node you have installed. To do this, edit file

In this file, add

Now you need to wait like 5 minutes for Munin master to fetch the data. Munin master run the command /usr/bin/munin-cron to fetch data from every configured nodes.

If you have any problem with updating data, check the log files for more info.

/var/log/munin/munin-update.log => is the log file for munin master.

/var/log/munin/munin-node.log => is the log file for munin node.

Make sure you can connect to port 4949 of node server from master. If any firewall blocking, you need to open the port for munin to fetch the data.

netdata

To install netdata, run

Once installed, you will be able to see servers stats at

http://your-ip:19999

Stop/start/restart netdata

Install netdata on ArchLinux

sed

sed can be used to replace text in a file.

g = Global, replace everything in a file.
s = substitute text
-i = update the file.

Delete lines matching string

To delete lines having a string and print result.

To update the file, use -i option