Pfsense on hdd or flash memory?
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I'm about to buy a shuttle pc to use with pfsense but I'm wondering what storage to use.
Is it best to use the internal hdd or a flash cart? -
If you plan on installing packages, use a hard disk.
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Has the advent of SLC compact flash changed the situation a little bit? I'm thinking our next box will be either SLC SSD or SLC CF. Many have said there are no write limitations on these new style cards.
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There are still write limitations, they're just higher with professional level units.
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With modern wear-leveling algorithms you "should" not hit the write-limitation.
Assume a disk of 4 GB.
If you write constantly with 50 MB/s to the disk you would write every ~80 seconds to the same cell.
4096/50 = 81.92
Assume conservatively that you can write 100'000 times to a single cell on an expensive card (some claim to be able to write 1'000'000 times)
100'000 * 80s = 8'000'000s
8'000'000s / 60 = 133'333.3 min
133'333.3 min / 60 = 2222'.2 hours
2222.2 hours /24 = 92.6 daySo if you write constantly with the maximum speed to a disk with a conservative assumption of maximum 100'000 writecycles the card would start to show first signs of failure after 93 days.
Of course if you take a 16 GB card (*4),
"only" 10 MB/s (*5, still a lot of disk traffic…)
and 1'000'000 writecycles (10)
you have 93 days 1054 =18518 day
18518 / 365 = 50.7 years.But the more expensive cards are about the same price as a harddisk ;)
