How to set up a cron schedule for every 12 hours at 6am and 6pm?

[chengka]

I've read several questions about using cron to schedule searches and I haven't seen a format the specifies every 12 hours at 6am and 6pm. I tried a few things like
0 6/12 * * * and even 0 (6,18) * * * to no avail.
Can it be done?

[jdunlea · Accepted solution]

Have you tried the following:

* 6,18 *  * *

[chengka]

Wow, so simple and I tried lots of complicated permutations. Thank you.