升级CentOS上的Apache 2到最新版，可采用以下两种方法：
sudo cp -r /etc/httpd /etc/httpd_backup，sudo cp -r /var/www/html /var/www/html_backup。sudo yum update。sudo yum install epel-release。sudo yum install httpd，若需特定版本，可使用sudo yum install httpd-版本号。sudo systemctl restart httpd。httpd -v或apachectl -v。tar -zxvf httpd-版本号.tar.gz，然后cd httpd-版本号。sudo yum groupinstall "Development Tools"，sudo yum install apr-devel apr-util-devel pcre-devel。./configure --prefix=/usr/local/apache2，可根据需要添加其他选项。make，sudo make install。sudo ln -s /usr/local/apache2/bin/apachectl /usr/sbin/apachectl。sudo /usr/local/apache2/bin/apachectl start。/usr/local/apache2/bin/apachectl -v。
