NAS

[Maurice Hilarius]

>Where you said:

>Hi,
>in our Institute we have been buying 3ware cards to build this kind
>of servers for more than an year now, and we are quite satisfied with them.

Us as well. Very good product, no hardware failures, excellent support from 
3Ware.

>After a very bad experience with IBM 75GB disks (14 failed disks out of 34),

Yes, that WAS scary. We were lucky and missed that. We sold some of  the 
earlier, trouble free ones, and did not buy any of the lemon latter ones. 
What really disturbed me was the way IBM tried to dodge liability on these.

>lately we have bought only Seagate 80GB and didn't have any problems
>(at least not more than expected failure rate).
>Now we have to buy another server and we are doubtful about continuing
>with "reliable" Seagates 80GB or "risking" with Maxtor 160GB. What's your
>experience with these disks?

The Seagate's have been OK, the newer Western Digitals also, with typical 
failure rates around 5%.
The Maxtor 160''s have been excellent! We have shipped well over a thousand 
now, with NO ( read zero, nada) failure rate. Best drive we have ever sold 
for reliability.


>Another point. You say that with Linux software RAID you get a much higher
>performance: how much do you pay in term of CPU usage for a RAID-5 array?

It scales about evenly with the data rate. There is no such thing as a free 
lunch. You move twice as much data, your CPU usage goes up too.
Using bonnie++ on a RAID5 of 16 disks, when doing the sequential block 
write part of the test CPU use goes to around 40% ( of one CPU).
Fortunately the dual Athlon boards are inexpensive, so we use a Tyan dual, 
and that means we have a CPU that can be dedicated to disk I/O and one for 
NFS if needed, with a very minimal cost.


>Thanks in advance,
>Massimo Biasotto


With our best regards,

Maurice W. Hilarius       Telephone: 01-780-456-9771
Hard Data Ltd.               FAX:       01-780-456-9772
11060 - 166 Avenue        mailto:maurice at harddata.com
Edmonton, AB, Canada      http://www.harddata.com/
    T5X 1Y3

2.3TB RAID5 NAS server - dual AthlonMP CPU, Linux, $10,995 CAD / $6850 USD