SYSadmin.lk | Linux Tips, Hacks, Tricks, and Tutorials

35 Basic Linux Commands in Sinhala

1 month ago4 weeks agoPrabath ThalangamaComment(0)

1) pwd command ඔබ සිටින වත්මන් වැඩ කරන ඩිරෙක්ටරියේ (ෆෝල්ඩරයේ) මාර්ගය සොයා ගැනීමට pwd විධානය භාවිතා කරන්න .

[prabath@mail ~]$ pwd
/home/prabath

1 2	[prabath@mail ~]$ pwd /home/prabath

2) cal command වත්මන් මාසයේ දින දර්ශනය පෙන්වයි.

[prabath@mail ~]$ cal
November 2020 
Su Mo Tu We Th Fr Sa
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30

[prabath@mail ~]$ cal

November 2020

Su Mo Tu We Th Fr Sa

1 2 3 4 5 6 7

8 9 10 11 12 13 14

15 16 17 18 19 20 21

22 23 24 25 26 27 28

29 30

3) echo command මෙම command එක ඔබ ඇතුල් කරන text එක නැවත පෙන්වයි. shell script වලදී ඉතා වැදගත් වේ .

[prabath@mail ~]$ echo "sysadmin.lk"
sysadmin.lk

1 2	[prabath@mail ~]$ echo "sysadmin.lk" sysadmin.lk

4) date command වත්මන් වේලාව සහ දිනය පෙන්වයි..

[prabath@mail ~]$ date
Thu Nov  5 01:55:55 +0530 2020/pre&gt;

5) whoami command
මෙම විධානය මඟින් දැනට පුරනය වී ඇති පරිශීලකයා හෙළි කරයි.

[prabath@mail ~]$ date

Thu Nov 5 01:55:55 +0530 2020/pre>

5) whoami command

මෙම විධානය මඟින් දැනට පුරනය වී ඇති පරිශීලකයා හෙළි කරයි.

[prabath@mail ~]$ whoami 
prabath

1 2	[prabath@mail ~]$ whoami prabath

6) […]

Apache LAMP Red hat linux Web Hosting

Setup Let’s Encrypt to Create SSL Certificates

7 months ago7 months agoPrabath ThalangamaComment(0)

Before you Begin Complete the steps for setting your Server / VPS hostname and timezone. Complete the steps in our Securing Your Server guide to create a standard user account, harden SSH access, and remove unnecessary network services. Update your server’s software packages:CentOS

sudo yum update &amp;&amp; sudo yum upgrade

1 2	sudo yum update && sudo yum upgrade

Debian / Ubuntu

sudo apt update &amp;&amp; sudo apt upgrade

1 2	sudo apt update && sudo apt upgrade

Download and Install Let’s Encrypt Install the […]

Asterisk Red hat linux

Securing Asterisk IP-PBX with Fail2Ban

8 months agoPrabath ThalangamaComment(0)

What is Fail2Ban? Any service that is exposed to the internet is susceptible to attacks from malicious parties. If your service requires authentication, illegitimate users and bots will attempt to break into your system by repeatedly trying to authenticate using different credentials. A common example of this is with SSH, which will be the subject […]

Nagios android and IOS mobile notifications

nagios Red hat linux Shell scripting

Configure Android / IOS notificationfor Network Monitoring With Nagios

8 months ago8 months agoPrabath ThalangamaComment(0)

Download Source File This PHP API script reads Nagios status.dat file and return the JSON result. This API is desinged for Nagios Client unofficial Nagios status monitoring app. Step 1 Upload nath_status.php to your Nagios web root folder. ###Nagios Core’s 3.5.1 default Web Root folder Web Root Folder – Centos /usr/share/nagios/html/ ###Nagios Core’s default Web Root folder Web […]

Red hat linux

How to remove powered by phplist

8 months ago8 months agoPrabath ThalangamaComment(0)

If that’s what you want to do, the following hack will do it (it looks like a cleaner solution would require figuring out where the [SIGNATURE] in the email template is coming from and removing that). These instructions are for phplist version 2.10.2. Search lists/admin/sendemaillib.php for $text[“signature”] = “\n\n–\nPowered by PHPlist, www.phplist.com –\n\n”; Immediately after that line, add the line (or replace […]

MySQL Red hat linux

How to re-sync the Mysql DB if Master and slave have different database incase of Mysql replication?

June 19, 2019June 19, 2019Prabath ThalangamaComment(0)

This is the full step-by-step procedure to resync a master-slave replication from scratch: At the master: And copy the values of the result of the last command somewhere. Without closing the connection to the client (because it would release the read lock) issue the command to get a dump of the master: Now you can release the […]

Red hat linux

Install and configure LSYNCD on Centos 7

December 5, 2018December 5, 2018Prabath ThalangamaComment(0)

Enviroment: – Server01.192.168.30.201 – Server02.192.168.30.202 – Directory to be Sync : “/opt/web/htdocs/prompt and /opt/vxml ” 2.Step Key based authentication Configuration -Login to Master server & generate the public and Private keys using the following command:

[root@server01 ~]# ssh-keygen -t rsa
[root@server01 ~]# ssh-copy-id -i /root/.ssh/id_rsa.pub root@192.168.30.202

1 2	[root@server01 ~]# ssh-keygen -t rsa [root@server01 ~]# ssh-copy-id -i /root/.ssh/id_rsa.pub root@192.168.30.202

2.Step Installation Lsyncd

[root@server01 ~]# yum install epel-release
[root@server01 ~]# yum install lsyncd -y

1 2	[root@server01 ~]# yum install epel-release [root@server01 ~]# yum install lsyncd -y

3.Step Lsyncd Configuration

settings  {
 logfile = "/var/log/lsyncd.log",
 statusFile = "/var/log/lsyncd.stat",
 statusInterval = 2,
}
sync{
 default.rsync,
 source="/opt/web/htdocs/prompt",
 target="192.168.30.103:/opt/web/htdocs/prompt",
 rsync={rsh ="/usr/bin/ssh -l appadmin -i /home/appadmin/.ssh/id_rsa",}
}

sync{
 default.rsync,
 source="/opt/vxml",
 target="192.168.30.103:/opt/vxml",
 rsync={rsh ="/usr/bin/ssh -l appadmin -i /home/appadmin/.ssh/id_rsa",}
}

settings {

logfile = "/var/log/lsyncd.log",

statusFile = "/var/log/lsyncd.stat",

statusInterval = 2,

}

sync{

default.rsync,

source="/opt/web/htdocs/prompt",

target="192.168.30.103:/opt/web/htdocs/prompt",

rsync={rsh ="/usr/bin/ssh -l appadmin -i /home/appadmin/.ssh/id_rsa",}

}

sync{

default.rsync,

source="/opt/vxml",

target="192.168.30.103:/opt/vxml",

rsync={rsh ="/usr/bin/ssh -l appadmin -i /home/appadmin/.ssh/id_rsa",}

}

Start and enable the lsyncd service using the following commands:

[root@server01 ~]# systemctl enable lsyncd
[root@server01 ~]# systemctl start lsyncd

1 2	[root@server01 ~]# systemctl enable lsyncd [root@server01 ~]# systemctl start lsyncd

[…]

MySQL Red hat linux

Upgrade MySQL to Version 5.6 in CentOS

November 8, 2018Prabath ThalangamaComment(0)

Backup all the database and stop mysql

 mysqldump -u (userid) -p (password) --all-databases > all-databases.sql
service mysqld stop

1 2	mysqldump -u (userid) -p (password) --all-databases > all-databases.sql service mysqld stop

Download the Repo for MySql 5.6

wget http://dev.mysql.com/get/mysql-community-release-el6-3.noarch.rpm/from/http://repo.mysql.com/

1	wget http://dev.mysql.com/get/mysql-community-release-el6-3.noarch.rpm/from/http://repo.mysql.com/

Install the repository from the local file

yum localinstall mysql-community-release-el6-3.noarch.rpm

1	yum localinstall mysql-community-release-el6-3.noarch.rpm

Install the latest MySql

yum install mysql-community-server
service mysqld start

1 2	yum install mysql-community-server service mysqld start

Configure MySQL to start automatically on Server Reboot

chkconfig mysqld on
chkconfig —list mysqld

1 2	chkconfig mysqld on chkconfig —list mysqld

Need to apply some tweaks Its not like the previous versions that tweaks are not required. From Version […]

Red hat linux

How to Set up Nginx High Availability with Pacemaker and Corosync

November 8, 2018November 8, 2018Prabath ThalangamaComment(0)

Prerequisites 2 or more CentOS 7 Serverpre web01 10.0.15.10 web02 10.0.15.11 web03 10.0.15.12 Floating IP Address 10.0.15.15 Root Privileges What we will do: Map the Host File Install Epel Repository and Nginx Install and Configure Pacemaker, Corosync, and Pcsd Create and Configure the Cluster Disable STONITH and Ignore the Quorum Policy Add the Floating-IP and […]

Red hat linux

Setting up the Basic High-Availability Cluster on Centos/RHEL 7

September 26, 2018Prabath ThalangamaComment(0)

Networking: We have two nodes that are reachable by below Networks: 10.1.1.0/24 : Cluster heartbeat vlan. 172.16.1.0/24 : LAN with access to the Internal LAN network and Internet. We have set the following hostnames:

[master ~]# hostnamectl set-hostname master.sysadmin.lk
[client ~]# hostnamectl set-hostname client.sysadmin.lk

1 2	[master ~]# hostnamectl set-hostname master.sysadmin.lk [client ~]# hostnamectl set-hostname client.sysadmin.lk

We defined the Hostname and IP Address in “/etc/hosts” file(On both the nodes), as shown below;

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

172.16.1.1        master.sysadmin.lk   #Physical IP Address of NODE1
172.16.1.2        client.sysadmin.lk   #Physical IP Address of NODE2
10.1.1.1          NODE1               #HeartBeat IP Addr of NODE1
10.1.1.2          NODE2               #HeartBeat IP Addr of NODE2

127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4

::1 localhost localhost.localdomain localhost6 localhost6.localdomain6

172.16.1.1 master.sysadmin.lk #Physical IP Address of NODE1

172.16.1.2 client.sysadmin.lk #Physical IP Address of NODE2

10.1.1.1 NODE1 #HeartBeat IP Addr of NODE1

10.1.1.2 NODE2 #HeartBeat IP Addr of NODE2

To setting up […]