IDE RAID card recommendation?

[trossachs]

Can somebody pls recommend an IDE RAID card for a server? The box will be running, Apache, Postifx and possibly MySQL, 10 plus. Users all bar one, accessing via the net. Why do you recommend what you do? thx

[adaptr]

3Ware Escalade.

Quality and performance without compromise.
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>>> emerge (3 of 7) mcse/70-293 to /
Essential tools: gentoolkit eix profuse screen

[Bob P]

on a related topic, what about a less mission-critical application for the home desktop? i know that the 3ware controllers are great, but are the offerings like the LSI MegaRAID controller any good? there's a huge price differential.

[adaptr]

AFAIK, none of the under-$200 controllers offer true hardware RAID, so if that is what you desire you're going to have to shell out.

But if you have a reasonably spiffy system you might get software RAID-5 without too much of a performance penalty.

That would depend on the specifics of the card you're buying.

The cheapest ones (the Promise and Highpoint fakes) don't give you any hardware capabilities other than the trivial one that allows you to address the RAID array as one device - which can also be done in software.

Somewhat higher up the scale are software-assisted RAID cards, which wil typically offer some kind of parity / buffering functionality in hardware, but which nevertheless still have to be controlled from software.

I've seen Adaptec IDE cards which do carry quite a price tag if they're fake, so these might actually be hardware too, but I've never seen them used.

Again, software versus hardware RAID does not mean mission-critical or not - it means you either get a decent hardware solution or you get crap that could be fully emulated in software anyway, so all you're really getting is the extra IDE ports.

I'd say look into a lower-end 3Ware IDE with 2 channels.
_________________
>>> emerge (3 of 7) mcse/70-293 to /
Essential tools: gentoolkit eix profuse screen

[Bob P]

hmm. i've never heard of "fake" RAID cards before. what is the difference in how RAID is implemented on real RAID cards, software assisted fake RAID cards, and fake RAID cards?

[adaptr]

I thought I explained that pretty well in the above post...

There are, basically, 3 "levels"or types of IDE raid:

The lowest and cheapest is the Promise / Highpoint scheme that's often built onto mainboards - it does absolutely nothing for you in hardware except allow the OS to see the array as one drive, as HW RAID does.
This basically means all you get are extra IDE ports, which can be nice.
But the quality of those IDE ports doesn't come close to a decent IDE chipset like the Intel PIIX4, which is still unbeaten as far as standard mainboard support is concerned.

The second rung is filled by those cards that actually offer some hardware assistance to doing striping, mirroring or parity operations, but they still have to be controlled from the OS.
These give you extra IDE ports and a few hardware functions the OS can make use of - note the can, you will need drivers for this!

Real RAID, on the other hand, does everything in hardware - to the OS, it only is one drive, and it can only be managed through its dedicated firmware.

That includes the RAID-0, 1 and 5 error-checking and parity operations, (re-)building the array, and buffering read and write operations (which is often far more advanced than for single IDE drives).

Check www.pcguide.com for more information than you need about RAID levels.
_________________
>>> emerge (3 of 7) mcse/70-293 to /
Essential tools: gentoolkit eix profuse screen

[trossachs]

Well I managed to get hold of an Adaptec ATA RAID 1200A card, with on-board chip. I can setup the array in DOS, but when I try and install Gentoo, it does not see it. Should there be some modules I should call from the command line before I run setup?