Category: Linux

  • Virtualmin Hosting Control Panel

    To install Virtualmin on Ubuntu, run

    wget http://software.virtualmin.com/gpl/scripts/install.sh
bash install.sh

    To install with Nginx, run

    wget http://software.virtualmin.com/gpl/scripts/install.sh
bash install.sh --bundle LEMP

    Auto Script install

    /usr/share/webmin/virtual-server/scripts

    To bakup a site using the command line

    virtualmin backup-domain --domain serverok.in --dest /backup/ --all-features --newformat

    Back to Hosting Control Panel

  • Enable LetsEncrypt SSL in ISPConfig

    Login to ISPConfig at

    https://your-server-ip:8080

    On main menu, click on “Sites”. It will show all available web sites on your server.

    ISPConfig

    Click on the domain on which you need LetsEncrypt SSL installed.

    On Next page, click the check boxes “SSL” and “LetsEncrypt”.

    ISPConfig LetsEncrypt Free SSL

    Click “Save” button. In few minutes you will get SSL installed on your web site.

    See LetsEncrypt

  • Install tmux on CentOS 6

    tmux is a terminal emulator. It work like screen, but have more features.

    CentOS 6 do not come with tmux, you need to enable rpmforge repository.

    http://repoforge.org/use/

    On CentOS 6 64 bit, run

    rpm -ivh http://repository.it4i.cz/mirrors/repoforge/redhat/el6/en/x86_64/rpmforge/RPMS/rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm
yum install tmux

  • webmin

    Webmin is an open source control panel to manage Linux and FreeBSD servers.

    http://www.webmin.com

    Download Latest source distribution from

    http://www.webmin.com/download.html

    To install webmin in Ubuntu/debian, edit

    vi /etc/apt/sources.list

    Add

    deb https://download.webmin.com/download/repository sarge contrib

    On Debian 11, Ubuntu 22.04 or higher, add the following

    deb [signed-by=/usr/share/keyrings/jcameron-key.gpg] https://download.webmin.com/download/repository sarge contrib

    Add GPG key

    cd /root
wget https://download.webmin.com/jcameron-key.asc
apt-key add jcameron-key.asc

    On Debian 11, Ubuntu 22.04 or higher.

    cd /root
wget https://download.webmin.com/jcameron-key.asc
cat jcameron-key.asc | gpg --dearmor >/usr/share/keyrings/jcameron-key.gpg

    Install webmin with apt

    apt-get update
apt-get install apt-transport-https
apt-get install webmin

    webmin access log

    /var/webmin/webmin.log

    LetsEncrypt SSL for webmin server
    Webmin create new admin user from command line
    Change MySQL root password in Virtualmin

    See Hosting Control Panel

  • sar

    Enable sar in Ubuntu

    install sysstat on CentOS

    View Past Performance Data With sar

    To see stats for the previous day, run

    sar -f /var/log/sysstat/saDD

    Where DD is day of the month. For example, to see stats for 10th, run

    sar -f /var/log/sysstat/sa10

  • Enable sar in Ubuntu

    On Ubuntu, when i run sar, i get error

    root@localhost:~# sar
Cannot open /var/log/sysstat/sa31: No such file or directory
Please check if data collecting is enabled
root@localhost:~#

    This is because sysstat is not enabled by default on Ubuntu, to enable, edit file

    vi /etc/default/sysstat

    Find

    ENABLED="false"

    Replace with

    ENABLED="true"

    Now restart sysstat

    systemctl restart sysstat

    See sar

  • Backup with tar

    To backup a site using tar, i created a shell script.

    mkdir /usr/serverok/
vi /usr/serverok/backup-daily.sh

    With following content

    #!/bin/bash

/bin/tar zcvhf /backup/daily/backup.tgz /home/serverok.in/public_html/

    For weekly backup

    cp /usr/serverok/backup-daily.sh /usr/serverok/backup-weekly.sh
sed -i 's/daily/weekly/g' /usr/serverok/backup-weekly.sh

    Make it executable

    chmod 755 /usr/serverok/backup-daily.sh
chmod 755 /usr/serverok/backup-weekly.sh

    Create backup folders

    mkdir  -p /backup/weekly
mkdir  -p /backup/daily

    Set cronjob

    crontab -e

    Add

    @weekly /usr/serverok/backup-weekly.sh  > /var/log/backup-weekly.log 2>&1
@daily /usr/serverok/backup-daily.sh  > /var/log/backup-daily.log 2>&1

    See backup

  • automysqlbackup

    Auto backup all your MySQL databases daily, weekly and monthly.

    To install on Debian/Ubuntu, run

    apt install automysqlbackup -y

    To manually backup, run

    automysqlbackup

    MySQL backups will be stored in folder

    /var/lib/automysqlbackup/

    See backup

  • zfs

    Install zfs file system on Ubuntu

    apt install -y zfs

    Listing ZFS file systems

    root@ns3048991:~# zfs list
NAME                       USED  AVAIL  REFER  MOUNTPOINT
rpool                     1.12T   654G   104K  /rpool
rpool/ROOT                5.50G   654G    96K  /rpool/ROOT
rpool/ROOT/pve-1          5.50G   654G  5.50G  /
rpool/data                1.11T   654G    96K  /rpool/data
rpool/data/vm-101-disk-0   103G   748G  9.29G  -
rpool/data/vm-101-disk-1  1.01T  1.65T    56K  -
rpool/swap                4.25G   658G   289M  -
root@ns3048991:~#

    List pools

    root@ns3048991:~# zpool list
NAME    SIZE  ALLOC   FREE  EXPANDSZ   FRAG    CAP  DEDUP  HEALTH  ALTROOT
rpool  1.81T  15.4G  1.80T         -     0%     0%  1.00x  ONLINE  -
root@ns3048991:~#

    Show current IO usage

    root@ns3048991:~# zpool iostat
              capacity     operations     bandwidth 
pool        alloc   free   read  write   read  write
----------  -----  -----  -----  -----  -----  -----
rpool       15.8G  1.80T     28     46   319K  2.14M
root@ns3048991:~#

    To see status

    root@ns3048991:~# zpool status
  pool: rpool
 state: ONLINE
status: Some supported features are not enabled on the pool. The pool can
	still be used, but some features are unavailable.
action: Enable all features using 'zpool upgrade'. Once this is done,
	the pool may no longer be accessible by software that does not support
	the features. See zpool-features(5) for details.
  scan: none requested
config:

	NAME        STATE     READ WRITE CKSUM
	rpool       ONLINE       0     0     0
	  mirror-0  ONLINE       0     0     0
	    sda2    ONLINE       0     0     0
	    sdb2    ONLINE       0     0     0

errors: No known data errors
root@ns3048991:~#

    Setup ZFS file system in Ubuntu

  • sendmail

    To test mail using sendmail, use

    sendmail -f [email protected] [email protected]
From: Sender Name 
Subject:  Test Mail
This is a test message.
.

    Dot in last time tell sendmail that message body is ended and it can send mail.

  • maldet

    Sent maldet scan report to email

    To install maldet, run

    cd /usr/local/src
wget http://www.rfxn.com/downloads/maldetect-current.tar.gz
tar xvf maldetect-current.tar.gz
cd maldetect-1*
./install.sh

    Configure Maldet to sent email

    sed -i 's/email_alert="0"/email_alert="1"/g' /usr/local/maldetect/conf.maldet
sed -i 's/email_addr="[email protected]"/email_addr="[email protected]"/g' /usr/local/maldetect/conf.maldet

    Update Maldet

    maldet -d && maldet -u

    To scan everything, run

    maldet -a

    To scan a folder

    maldet -a /path/to/folder

    To scan all public_html folders

    maldet --scan-all /home?/?/public_html

    To scan content created/modified in last 10 days, run

    maldet --scan-recent /home?/?/public_html 10

    Ignore a folder in maldet

  • self signed ssl

    To generate self signed SSL certificate, run

    openssl genrsa -out DOMAIN_NAME_HERE.key 2048
openssl req -new -x509 -key DOMAIN_NAME_HERE.key -out DOMAIN_NAME_HERE.crt -days 3650 -subj /CN=DOMAIN_NAME_HERE

    Or

    openssl req -newkey rsa:2048 -nodes -keyout DOMAIN_NAME_HERE.key -x509 -days 3650 -out DOMAIN_NAME_HERE.crt

    Add Self Signed SSL to Apache Virtual Host

    Let’s say your Apache virtual host entry is

    <VirtualHost *:80>
    ServerName serverok.in
    ServerAlias www.serverok.in
    ServerAdmin [email protected]
    DocumentRoot /home/serverok.in/public_html
    <Directory "/home/serverok.in/public_html">
        Options All
        AllowOverride All
        Require all granted
        Order allow,deny
        allow from all
    </Directory>
</VirtualHost>

    Create a new VirtualHost entry based on this, say yourdomain-ssl.conf, in this new file

    Find

    <VirtualHost *:80>

    Replace with

    <VirtualHost *:443>

    Find line starting with

    DocumentRoot

    Add Below

    SSLEngine on
SSLCertificateFile /etc/ssl/yourdomain.crt
SSLCertificateKeyFile /etc/ssl/yourdomain.key

    Now restart Apache

    systemctl restart apache2

    How to access the website using a Self-signed SSL certificate

    See SSL