Trouble with excludes in web interface

I’m using the web interface to set up backups, and I’m having trouble making excludes work. I think the easiest way for me is probably to edit the filters as text, which I selected from the Filters popup menu. Let’s say I want to back up /var/www but don’t want /var/www/html/dir1 and /var/www/html/dir2 included. I thought I could just go:
-html/dir1/;-html/dir2/
but that doesn’t seem to be working. Are the exclude paths relative to the backup location or do I need to give full paths? What else might I be doing wrong?

Thanks.

Use only full paths.

For starters, I believe each filter needs to be on it’s own line, not separated by a semicolon - so you may find this works better for you.

-html/dir1/
-html/dir2/

Otherwise, consider looking through some of the examples in the Filters documentation.