11/3/07

NLB, DFS, 2nd Shot

Last night I was lying on the floor in my room, staring at the laptop screen, wondering why my eyes felt strained...it was because the brightness on my screen was turned way down. Protecting my eyes suddenly feels very important to me as they are starting to feel tired. From now on I will work in good lighting w/ a bright laptop screen. I'm non-commitally contemplating a 22" LCD from Amazon for $230. However, I could replace my digital camera w/ a Canon SD1000 for $60 less than that.

Last night I learned about Network Load Balancing (NLB) which sounds like it's best for webservers and SQL databases. With "client affinity" enabled it can even maintain a session between a single client and a single server in the background (needed for databases). Clustering is only available in 2003 Enterprise ($800+ on eBay) and DataCenter editions. Clustering is more for high availability of changing network resources and requires a single point of storage that all the clustered servers can access. That point is called a quorum (probably a SAN or RAID setup).

Distributed File System (DFS) is used to organize file shares from multiple servers into a single point of access (e.g. a drive letter). It can also replicate data placed in one space into another geographical site (for faster access) or to a different server (for seamless failover/backup). It seems kind of clunky though and I have a hard time envisioning a really good use of DFS apart from fault tolerance for non-clustered file servers.

Registered for Microsoft's second shot offer (valid until January 30, 2008) which gives you one free retake on each $125 exam that you fail. I hope I don't need it!

Helpful thoughts on NLB unicast vs. multicast.

I read about Fibre Channel in Wikipedia & it sounds like it's a bus technology that is just a bit (25%) faster than SATA (and probably a lot more expensive). You would need need 2-3x 1Gb NICs teamed together to completely harness the power of a single SATA drive.