Web-N00b

OpenVZ supports VPN inside a container via kernel TUN/TAP module and device.
To check availability of TUN module on your server (not VPS), type following command:
lsmod | grep tun
you should see something like:

tun 40260 1
vznetstat 24189 3 tun,ip_vznetstat,ip6_vznetstat

if output is empty, you can’t continue.

To allow VPS to use the TUN/TAP device you need to do following (lets take for example VPS with ID 99):
vzctl set 99 –devnodes net/tun:rw –save
vzctl set 99 –devices c:10:200:rw –save
vzctl stop 99
vzctl set 99 –capability net_admin:on –save
vzctl start 99
vzctl exec 99 mkdir -p /dev/net
vzctl exec 99 chmod 600 /dev/net/tun

To check if module was enabled inside VPS, type following:
cat /dev/net/tun

output should be like:
cat: /dev/net/tun: File descriptor in bad state

Partially taken from here, but some info is outdated, some missing, because I was unable to finish setup with those manual.

So, what we have?
Freshly installed Centos 7 and root access.
Steps need to be done:

1. yum -y update
2. yum localinstall -y https://dev.mysql.com/get/mysql80-community-release-el7-1.noarch.rpm
3. yum --disablerepo=mysql80-community --enablerepo=mysql57-community install mysql-community-server mysql-devel
4. systemctl start mysqld.service
5. systemctl enable mysqld.service

More »

The most common problem with postgresql – it uses ASCII charset by default, and if you want to create database in UTF8, you can see the error “(UTF8) is incompatible with the encoding of the template database”.

Use these few easy steps to solve it:

1. su - postgres
2. psql
3. UPDATE pg_database SET datistemplate = FALSE WHERE datname = 'template1';
4. DROP DATABASE template1;
5. CREATE DATABASE template1 WITH TEMPLATE = template0 ENCODING = 'UTF8';
6. UPDATE pg_database SET datistemplate = TRUE WHERE datname = 'template1';
7. \c template1
8. VACUUM FREEZE;

Now you can use template1 for creation of your database.