Generally you can use "curl" or "wget" to simply visit websites. If you cannot install these, it's possible to use a simple script implemented in tcl, perl or python. If you want your job to run twice a day, pick a set of hours. Here, I chose 10 minutes after 6am and 7pm. Use "crontab -e" to edit the cron file and insert the following line.

10 6,19 * * * wget --spider -nv http://my.url.com/cgi-bin/mybot >/dev/null

Errors will be emailed to your user account. If you don't want this, follow up and we'll see what we can do.