基于域名的虚拟主机
server {
    listen 80;
    server_name www.example.com;
    ...
}
server {
    listen 80;
    server_name www.test.com;
    ...
}

基于ip的虚拟主机
server {
    listen 10.0.0.88:80;
    root 88.com;
    index index.html;
}
server {
    listen 10.0.0.87:80;
    root 87.com;
    index index.html;
}