apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName

Возможно вы тоже столкнётьсь с такой проблемой, делая restart Apache.

:~$ sudo service apache2 restart
* Restarting web server apache2
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName

Решение проблемы: поправить httpd.conf . Откройте терминал и введите

sudo nano /etc/apache2/httpd.conf

По умолчанию httpd.conf пустой. Просто добавьте строку в файл. ServerName localhost Сохраните и, наконец, перезапустите сервер.

sudo service apache2 restart

How to show console resolution in Ubuntu

To print console resoluton in Ubuntu:

cat /sys/class/graphics/fb0/virtual_size

Installation Wireshark on Ubuntu

Wireshark is a free and open-source packet analyzer. It is used for network troubleshooting, analysis, software and communications protocol development, and education. It is a very good helper of a network administrator and it rescued my network many times. You can install it on Ubuntu by running following commands in terminal:

sudo add-apt-repository ppa:n-muench/programs-ppa
sudo apt-get update
sudo apt-get install wireshark