SCSI or SATA ??

[SomethingClever]

So, in a Dually Opteron server .... what's the difference in having SCSI or Sata drives in a RAID config?

Reliability? Speed?

Probably a dumb question but .. o well!

 

[Tigerbiten]

SCSI was really designed for the server market.
Better MTBF so longer warrenty.
Higher spindle speed so faster access times.
Smaller market so higher cost.
Plus you can get 15 drives on each channel.

Now get a highend SCSI raid card on a 64 bit / 133 Mhz PCI-X bus.
Add to that some 15K dives in a raid 5 or even 1/0 and it will be quick.
But it will also cost at least 2x more than a SATA setup of the same size.

Luck..........

 

[defakto]

If you can foot the bill scsi all way for a high end server, if not, sata will "work" until you can upgrade to scsi.

 

[unhappy_mage]

Price per $, and performance are the two big differences. Sata is cheaper but slower, and probably less reliable too.

You get what you pay for.

 

[DougLite]

What are you going to do with the box? How many users at any given time? How large of files will be accessed? What percentage of disk activity is writes? What is your budget? These, and many more, are valid questions to ask when making choices on a storage system.

If you will be doing 90% reads for 10-15 users and only a handful of them will be accessing the drives concurrently, some SATA Seagate 7200.8 or Maxtor MaxLineIIIs will be more than adequate. OTOH, If you are serving a 100+ users at a time and have frequent writes to huge files nad highly random access patterns with long stroke seeks, then only SCSI dirves will deliver acceptable performance.

Post as much info as you can about the box's intended mission so that you can learn as much as possible about will be good drives for it.

 

[wetware interface]

well for money you can get a lot more scsi performance at a sacrafice of lower overall disk space by going used.

it really depends on your needs.

if you have limited budget but need large amounts of space plus the extra speed in that space (video editing) then a simple raid 5 array with 4 drives on sata with a cheaper raid 5 capable sata controller is a good option.

if your budget only allows for 3 sata drives go scsi with below recommended for as many drives as 2 sata would cost plus the cost savings of the cheaper controller will permit and buy one large sata drive for storage.

if you need more speed and a large amount of space isn't a requirment (database)
older 10k scsi drives in 8-9 gig capacities in raid 5 with an older scsi 180 raid controller card used is a really cheap option as you can pick the card up for $100 and the drives for $20-30 bucks apiece sometimes and on average for $50 apiece. this gives you more drives in a raid array for cheaper than sata and better raid performance with a space sacrifice overall.

also one benefit of scsi over sata is that if you have a good quality power supply with plenty of juice on the pwer rail but isn't a huge wattage scsi spins up the drives one at a time to avoid a power fluctuation on the power supply. sata doesn't. turn on the system and they spin all at once.