Init

One of the recent server upgrades called for the purchase of raid controller cards. I use software raid in Linux for its versatility and the L8i controllers can perform in hba (Host Bus Adapter) mode. These cards ship with Supermicro’s IT mode firmware which essentially lets all of the drives show up independently in linux.

Before I could see all that, I needed to get these cards into my case. Don’t be too upset when you first try to slide this card into your case and mobo (I have a Norco 4220 and Gigabyte EP45-UD3P) they will not fit at all. It appears as if the bracket is off on the Y axis by about a quarter inch, this is because these cards are UIO form factor.

Establishing my frame of reference

This can easily be resolved with some longer screws and nylon spacers. Be sure to use the original brackets as buying new brackets was really hard to figure out (If anyone knows the exact bracket for this then please let me know).

Using quarter inch nylon spacers for number ten machine screws (need to verify)

We used two spacers on each of the ‘posts’, it appeared that this resolved the issue as we got a good solid fit for both of the cards.

I have a friend that I talk about computer parts and prices with non stop, he spends a lot of time down in the trenches with enthusiasts and keeps his finger close to prices on almost all PC components. Recently he let me know that 500GiB Western Digital hard drives (WDC500AAKS) were going used for about $50. My original array was built out of 6 of these drives, and brand new 1TiB drives are hovering around $100. So a couple of fedex boxes later I am the new proud owner of some 1TiB drives.

I have heard horror stories about these drives regarding RAID arrays, with them dropping out for no reason and causing the array to degrade and rebuild. Looking a little further, in particular the newegg reviews, I found that by enabling TLER (Time-Limited Error Recovery) all of the issues with RAID on these drives are solved. In fact one of the only major differences between the Caviar line of HDDs from Western Digital and the RE line is this TLER feature. Lucky for the poor college kids in the computing crowd Western Digital makes a tool named WDTLER that will enable or disable TLER on Western Digital HDDs.

TLER exists because there are sometimes conflicts in whether the error handling should be undertaken by the HDD or the RAID controller, if TLER is not enabled the drive can be marked as unusable and cause significant performance degradation. With TLER enabled the HDD will wait for the RAID controller to resolve errors up to the amount of time that has been set. In my case Ihave set the drives to their recommended RAID times of 7 seconds.

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I am obsessed with disk space, and with that comes and obsession with redundancy. It is a fact that the hard disk drives you purchase will only work for a variable amount of time. Now this might be such a long time that you will upgrade/replace and never have a drive failure, but if you have ever had an unexpected drive failure and lost information then you know how terrible of an experience it is.

I need about 1.5 TiB to be comfortable with the amount of current bits I have, but I had a couple of WD 500AAKS in a machine alread and figured that I would max out the sata ports on a motherboard and use that machine as a dedicated file silo.

For my purposes I have chosen to run RAID 5 so that I can take maximum advantage of my 5 drives storage space and still have a redundant parity.

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