头部

<IfModule mod_rewrite.c>
RewriteEngine On

1.所有http自动跳转到https

RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://%{SERVER_NAME}/$1 [R=301,L]

2.所有abc.xxxx.com跳转到def.xxxx.com

RewriteCond %{HTTP_HOST} abc.xxxx.com$ [NC]
RewriteRule ^(.*)$ http://def.xxxx.com/$1 [R=301,L]