Install and modify Apache2 port in UBuntu

Install and modify the Apache2 port in UBuntu because the local machine has Nginx, so there is no need to install Apache2. However, to learn how to use icinga today, let's take a look at apache2. Now we are familiar with icinga and use Nginx to replace Apache2. The installation is simple: [plain] apt-get install apache2 and then auto start fails, because Nginx occupies port 80 and port 443. Find the/etc/apache2 directory through whereis apache2 and open ports under the directory. in the conf file, change all port 80 to port 81,443 to port 444. then, read the file comment and say the/etc/apache2/sites-enabled/000-default file is required. open the file and change [plain] <VirtualHost *: 80> to 81, then, the root directory is under/var/www. the/var/www/directory shows the index.html file [plain]