Configure certificate in HestiaCP

1. Backup current certificates in directory /usr/local/hestia/ssl/:

mv /usr/local/hestia/ssl/certificate.crt /usr/local/hestia/ssl/certificate.crt.old 

mv /usr/local/hestia/ssl/certificate.key /usr/local/hestia/ssl/certificate.key.old 

2. In directory /usr/local/vesta/ssl/ make symbol links to certificates, that we use on our site (for example: site.com):

ln -s /home/admin/conf/web/site.com/ssl/site.com.crt /usr/local/hestia/ssl/certificate.crt 

ln -s /home/admin/conf/web/site.com/ssl/site.com.key /usr/local/hestia/ssl/certificate.key 

3. Restart Hestia service:

service hestia restart

How to exit vim? And other required commands.

Vim is the most popular Linux text editor, it was created in 1978 and is used to present days.

Vim has two modes: “Command mode” where you can insert many commands, and “Insert mode” – where you can insert and edit text document. By default Vim open all documents in “Command mode”, to enter into the “Insert mode” – press button “i“.

The most asked question is – “How to exit Vim?” – it is very simple – in Command mode enter :q! and press Enter. This command exit Vim without saving any changes.

:q!

To save file – enter command :w <filename> and press Enter:

:w file.txt

To save file and exit Vim use command :wq and press Enter

:wq

How to uninstall program installed in Wine?

You just need to write in terminal command:

wine uninstaller

This command will start an Add/Remove applet similar to what you get in Windows, which will list your installed WINE programs.

Select program and press button “Uninstall”.

It was very simple 😉

How to set default browser in Debian Linux

To set default browser in Debian or Ubuntu open terminal and write command:

sudo update-alternatives --config x-www-browser

As you can see, we have four alternatives of browsers, installed in operating system, just enter number of browser and press Enter.

How to set permissions to files and folders in Linux terminal

There are there types of file permissions in Linux:

1. Owner permissions
2. Group permissions
3. Other permissions

Also you can set permissions for read, write and execute file for this three groups.

To set correct permissions for all files and folders in currend folder use command:

find . -type f -print0 | xargs -0 chmod 644
find . -type d -print0 | xargs -0 chmod 750

This commands will grant readm write, execute access for owner, read access for group and block all access for other users.

If you wand to grant access to files and folders for other users use commands:

find . -type f -print0 | xargs -0 chmod 665
find . -type d -print0 | xargs -0 chmod 751

Encrypt and decrypt files using GPG

To install GPG on your Debian/Ubuntu/Mint Linux operating system use command:

sudo apt-get install gpg

Default GPG folder is: /home/user/.gnupg. Generate private and public keys:

gpg --full-gen-key

Answer the several questions (encryption type: RSA, keysize: 4096 for better encryption, key expiration time, your name and email address) and press “O” if all changes are correct.

To view public keys use command:

gpg -k

To view secret gpg keys use command:

gpg -K

How to run custom file with Wine .exe in Linux Mint

To run Windows programs in Linux we use Wine. But how to open any file with exe program using Wine? For example we have 1.txt file. To run this file with notepad.exe use command:

wine "/home/user/notepad.exe" 1.txt

To associate some type of files with EXE program we can use shell script:

#!/bin/sh

QUICKPARLOCATION="/home/user/Notepad.exe"
PARAM=`winepath -w "$*" 2>/dev/null`
wine "$QUICKPARLOCATION" "$PARAM" &
exit 0

Put this file in /home/user/bin directory. Open file properties and in field “Open with” select Notepad.sh script:

How to install latest wine on Ubuntu or Linux Mint

The official WineHQ repository has a set of standard Wine packages that you can download and install on your system. Please follow these steps to do so:

Run the following command in the Terminal for adding i386 architecture before installing a 64-bit version of Wine:

sudo dpkg --add-architecture i386
Next add the WineHQ signing key:

wget -qO- https://dl.winehq.org/wine-builds/Release.key | sudo apt-key add -

Then run this command to import the other key for the WineHQ Repository:

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv F987672F

Now run the following command in order to add the relevant repository from the WineHQ:

sudo apt-add-repository 'deb https://dl.winehq.org/wine-builds/ubuntu/ bionic main'

Next update the Ubuntu package lists with the command:

sudo apt-get update

Now we can install latest stable version of Wine in Ubuntu or Linux Mint operating system:

sudo apt-get install --install-recommends winehq-stable

Linux how to fix ext4 filesystem

Sometimes if server is shutdown incorrect filesystem filesystem can be corrupted and loaded in “read only” mode.

To check file system status use command:

mount | grep /dev/sd

This command show filesystem status, if filesystem is read only – you will see “ro” status: /dev/sda2 on / type ext4 (ro,readonly,data=ordered)

To fix filesystem use command:

fsck /dev/sda2

This command will fix all errors on filesystem, To apply fix enter y on keybord. When fixing is complete reboot system and check filesystem again.

How to create and compare md5 checksum of files

To create md5 checksum of all files in folder use command:

md5sum /etc/*

This comment will show all md5 checksum in /etc directory:

To write this checksum in text document use command:

md5sum /etc/* >> /file.txt

To compare checksum of files in folder with checksum of files in text document use command:

md5sum -c /file.txt

If checksums match, near the file will be record “Success”, it means that the file has not changed. Otherwise it means that the file was edited by someone.

To check your system, regularly create checksum files for directories: /etc, /bin, /sbin, / lib

Use md5sub recursive in sub-directories

If You want to create md5 checksum of all files in all sub-directories use next command, it will create md5 checksum of all files in /etc directory:

find -type f -exec md5sum '{}' \; > md5sum.txt