$ crontab -e  # this pulls up the crontab file editor to which you append:
 
*/4 * * * * ls  /media/drive-you-want-alive

The */4 is equivalent to 0-59/4.

A couple advantage that I’d say my solution has is that it doesn’t require you to go futzing around with the crontab file, which on some systems you won’t have access to, and also, if the root of that drive is huge doing an ls on it can be a really big deal, way more of a deal than just touching an empty file. If that’s the case you could basically do hdactive in cron:

*/4 * * * * touch /media/drive-you-want-alive/.hdactive

And since hdactive requires significantly more setup and is therefore way more confusing than crontab, if you’ve got access to it, it’s probably the way to go.

I don’t have this problem myself, but doesn’t `ls` keep the drive spun up? I don’t like creating unnecessary files on the hard-drive, but if you don’t then – if you use `touch` – you have to change the modification date of some other file on the drive. So `ls` seems preferable, unless the o/s is caching the directory listing.

Also, I wouldn’t tend to run the script manually – that way you have to remember to do so every time you reboot your computer. I would omit the `sleep` so that it runs to completion & doesn’t hang around in the background. Then just add it to crontab so that it is automagically run every 4 minutes; I believe this is the crontab syntax:
0-59/4 * * * * ./hdactive.sh

2Thus saith the LORD, Learn not the way of the heathen, and be not dismayed at the signs of heaven; for the heathen are dismayed at them.

3For the customs of the people are vain: for one cutteth a tree out of the forest, the work of the hands of the workman, with the axe.

4They deck it with silver and with gold; they fasten it with nails and with hammers, that it move not.

which is pretty clearly just saying that it is woodsmen who cut trees out of the forest. But then if you look at the new international version you get:

2 This is what the LORD says:
“Do not learn the ways of the nations
or be terrified by signs in the sky,
though the nations are terrified by them.

3 For the customs of the peoples are worthless;
they cut a tree out of the forest,
and a craftsman shapes it with his chisel.

4 They adorn it with silver and gold;
they fasten it with hammer and nails
so it will not totter.

sounds pretty extremely different, although there is no mention of idols in either version, so it’s not that different. Certainly I don’t think that it is clear that it’s talking about idols instead of the pagan ritual that christmas is incontrovertibly derived from.