Note that in .htaccess files or within <Directory> containers in config files, the URL-path examined by RewriteRule *does not* contain a leading slash -- the path to "this directory" is stripped before mod_rewrite 'sees it.'
However, your code is not within a <Directory> container, and is evidently located in a server config file. Therefore, all URL-path patterns should start with a slash.
Note that the second rewritecond in the first rule is redundant, since it is a specific positive-match pattern just like that in the rule.
Also, the <VirtualHost> containers provide all the 'logic' needed to decide which port the traffic arrived on, so the RewriteConds examining %{SERVER_PORT} are unnecessary.
The tweaked version would look like this:
# Non-SSL vHost configuration
<VirtualHost *:80>
#
# Enable mod_rewrite rewriting engine
RewriteEngine on
#
# Redirect non-SSL /page2.html requests to port 81 (SSL)
RewriteRule ^/page2\.htm$ https://www.example.com/page2.htm [R=301,L]
</VirtualHost>
#
#
# SSL vHost configuration
<VirtualHost *:81>
#
# Enable mod_rewrite rewriting engine
RewriteEngine on
#
# Redirect SSL requests for all resources other than /page2.htm to port 80 (non-SSL)
RewriteCond %{REQUEST_URI} !^/page2\.htm$
RewriteRule ^/(.+)$ http://www.example.com/$1 [R=301,L]
</VirtualHost>
As implied here, concise and accurate comments are your friend... :)
Now consider this: Do you have 'objects' such as images, css files, or JS files that are shared between SSL and non-SSL pages? If so, then you may need to exclude those objects from HTTP/HTTPS redirection. Otherwise, you may get "Mixed secure/insecure content" warnings in the browser if a page is served with HTTPS but the objects included on that page are served with HTTP. If needed, this exclusion can be done by adding rewriteconds that look at the 'filetype' appended to the requested URL-path, e.g.
RewriteCond %{REQUEST_URI} !\.(gif|jpe?g|png|ico|css|js)$
If no objects are shared between SSL and non-SSL (and given the configuration implied by your post and your code, they may indeed not be), then this is not a concern.
Jim
