Can the onbord RAID controller support 2 arrays with ease?

[RickTw]

Hi,
I'm very new to RAID, but understand the concepts and how to setup an array etc, although I have only done it a couple of times.

I have an ML110G5 with onborad RAID controller.
In the past (with non raid systems) I have always had my OS on C:Drive and data on D:Drive.

I want to continue this practice with my ML110 using RAID 1, but I'm worried if the onboard controller will be able to handle two RAID1 arrays (Drive C:array 1) & (Drive D:array 2).

My question...
Is the chip robust enough to handle this, or will it be pushing it's limits and prone to errors?

[TTr]

Everything is relative in this case. If you have a high i/o demand from your server you should be looking at a better raid solution (SAS disk based) and even at a better server. For casual i/o that's what the ML110 and the onboard SATA raid system are for.

[marcus1234]

yes the chip is robust enough for this ,,
but if it is anything critical i would make a tape backup every day incremental one..

the servers that are 350 series and up have much better raid systems hardware based entirely,but cost more ....hmm..
I would also get a dat usb tape drive

points appreciated

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enjoy :)

[RickTw]

Thanks TTr and mark1234 for your feedback.

In response to both of your comments, I may have a fairly high i/o demand from the server, but looking at a better raid solution or higher spec server is not an option (financially) at the moment, hence my purchase of these machines. I am hoping they will suffice for the time being.

I will be hosting around 50 very small websites on each. I realise they are not ideal for this but... recession, etc

If I may elaborate on my question...

Scenario 1:
If I had my O/S -AND- my websites on a single array (on Drive C:) the RAID chip and disks would be busy running Windows AND serving webpages, ok...

Scenario 2:
But, having my websites on a 2nd array (D:) should in theory speed up the serving of these websites, as the 2nd array isn't having to manage all the I/O workload for the O/S stuff.

But... does the RAID chip have a preference to Scenario 1, or Scenario 2 (in terms of stability, reliability, performance) ?

[marcus1234 · Accepted solution]

both arrays are given equal io resources on the bus ,
except on boot as preferance is given for a short while to the array with the os,after it has had the intial boot query..

enjoy..

[marcus1234]

oops scenario 2 is a good choice

[RickTw]

OK thanks, I think I'm feeling a bit more reassured now. I definitley want to keep my data on a separate disk to the O/S.

One last query if that's OK with you...

Obviously the data takes priority and I definitely want that on a RAID array.
The O/S however, could easily be restored from a Ghost image in minutes.

So, what would you say to having a third scenario with 3 disks, where I have Windows on a single non-RAID HDD, and my data (D:) on a RAID1 array?

I assume this scenario is possible with the ML110G5? and I also assume it would take some of the strain off the controller chip by only having one array to manage?

I realise these machines are low spec, that's why I don't want to push them too hard.

[marcus1234]

rick
if the os i
but this would not really create any overhead as the data would be written from cache it would not be going over from disk to disk and using io transfers per say ,,

so no need to cut to a bare minimum

and feel free to ask thats why we are here

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[RickTw]

Thanks Mark, but I think you may have mis-typed your last response? - please could you clarify your first paragraph?

[marcus1234]

sure rick yes typo..

i will clarify


if you mirror the os
this would not really create any overhead as the data would be written from cache it would not be going over from disk to disk and using io transfers per say ,,

so no need to cut to a bare minimum

so basically I would mirror the OS aswell

and feel free to ask thats why we are here

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