I'm an Oracle DBA and familiar with various HA options and I've read your book on HA. I was wondering what kinds...
of solutions you might recommend for continuous availability (CA).
Continuous availability as in 100%, 24x7? I don't believe that there is any such thing possible with today's technology.
High availability (HA) is all about the pursuit of continuous availability (CA). HA is generally achieved by making different system components redundant. The more components you make redundant, the higher the level of availability you can achieve. However, as long as it takes time to switch over applications from one system or one site to another, there will always be some downtime.
I would argue that instead of pursuing CA, you should work to make things as highly available as you can. (The difference is subtle. Did you know that eBay has 2-3 hours of scheduled downtime every week? They found that by introducing this scheduled downtime, they can reduce the amount of unscheduled downtime the rest of the week. I believe that if they can do it, just about anyone can.
Hope this helps.
Evan L. Marcus
Editor's note: Do you agree with this expert's response? If you have more to share, post it in our .HcX6azlxeJg^0@.ee83ce2!viewtype=&skip=&expand=>Administrator Central discussion forum.
Dig Deeper on Data management tools
Related Q&A from Evan Marcus
Storage expert Evan Marcus compares software and hardware RAID and outlines the benefits and drawbacks of each.continue reading
This expert answer explains the purpose of creating LUNs and details reasons for creating multiple LUNs.continue reading
This advice details the hardware and software requirements for setting up two data servers in fail-safe cluster mode for high availability.continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.