things in italic are optional.
- HTTP only.
HTTPS, FTP, FTPS, etc are not allowed.
- User name and password are supported.
If your URL require HTTP Authentication, simply add user:pass@ before domain name.
You can add URL with domain.com, .net, .org, .co.uk, ..., .co.cc, .uni.cc, etc. There're some domain names restricted, such as google.com, yahoo.com, youtube.com, ...
- All ports are allowed.
Recommended ports are 80 (default), 8080 (HTTP Alternative), ...
- Must have either path or query.
It's often no need to set cron job with home page, e.g http://example.com/.
http://example.com/?q=backup (home page but have query), http://example.com/backup.php (has path), http://example.com/backup.php?mode=all&sendto=webmaster (has path and query) are allowed.
- All file extensions are allowed.
You can set cron job with file.php, .asp, .aspx, .py, .pl, .cgi, .html, .html, etc
- Fragment will be trimmed.
If your URL end with #fragment, e.g http://example.com/backup.php#useless, the #useless will be trimmed. The final URL will be http://example.com/backup.php. As fragment is used only by browser, web server don't know what fragment is inserted, so it's no need to add #fragment to your URL.
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