September 28, 2004 at 6:04 am
I've been asked to look into resilence with regard to providing 24/7/365 database service for an entirely database driven web content management system.
Virtually all my experience is as a development DBA/data analyst so I'm in over my head here.
If you have a cluster will service continue if either one of the servers fail or is there a primary node that can act as a single point of failure?
When would I use Active/Active and Active/Passive?
For this particular application I am thinking along the lines of having a completely separate SQL Server (cluster) looking after content maintenance and then the final data being replicated across to a SQL server (cluster) looking after the actual surfing of the site.
I know that RAID 5 has some issues with write performance, plus I read somewhere that when the drives begin to degrade there is a risk of RAID 5 copying the bad blocks across the array.
What I was considering was having the content maintenance database server using RAID 1+0 but the live server using RAID 5 as the content server will have a lot of writing taking place as part of the content processing where as the front end server will only have the results of the processing written across.
What should I consider with regard to other points of failure?
September 28, 2004 at 7:20 am
please see the below link for response:
http://www.sqlservercentral.com/forums/post.aspx?forumid=54&messageid=139052
Good Hunting!
AJ Ahrens
webmaster@kritter.net
September 30, 2004 at 10:04 am
This post needs a big reply, rather beyond me I'm afraid.
A few points, however:
- I'd go for RAID 0 + 1 it's far more write-efficient than RAID 5. Definitely worth the extra investment in disk.
- I wouldn't regard CPUs as a point of failure, I've never had any problems with them. Our biggest Server uses 4, maybe you should consider many more, 8 or more. Choose a scalable machine.
- Only had trouble with a motherboard once but have had lots of probs with network cards, here's your weak spot
- On the db side I suspect your weak spot will be lock contention, esp. with plenty of text & wide char fields. Bear this in mind when designing the app. & db
- Try Knowedge Base, Books Online, Microsoft's SQL Server home, websites such as SQLServerCentral.com for info about clustering. Maybe speak to an 'expert', maybe pay that person for their time .
- Your Development experience will be invaluable in helping to design an efficient schema and application. I've administered too many hastily written apps where the developers have disappeared just after implementation and just before before the whole thing grinds to a halt. All the hardware power & efficent networks in the world won't make a poorly designed app work well.
Good luck!
Viewing 3 posts - 1 through 3 (of 3 total)
You must be logged in to reply to this topic. Login to reply