Re: Oracle Data Guard

Yes, I'm awake. It's about impossible to have an afterdinner powernap these days.

On topic now. There was a thread recently on another list, for blacksmiths (some of you might know I convert an old 24m/72ft barge into a pleasure boat, if time permits).

Some guy asked: anyone used a sledgehammer before? did you like it? any challenge, or best practices?
Responses varyed from 'watch your fingers and toes' to 'very useful to insert unwilling screws'.

The analogy with Li's question is amazing....... (Dont take it personal Li, lots of people walked the trail you're following before you did)

It's about the approach of something: Hey, this is a tool, what can I use this for?

Data Guard is great and second to none, if used for the right problem. (the screw might get inserted better with the proper screwdriver) Data Guard can be great. I implemented it at some 20-40 sites (I stopped counting) and many more databases.
Data Guard can't solve any problem. It's always part of the total solution, which will have many more components.

Challenges: Many. Start with discovering the requirements of your business regarding High Availability: maximum recovery time, maximum data loss. Investigate all problems. Think of solutions. Think of problems for your solutions..... (Read my post of last Saturday)

Best Practices: Look for bad practices, war stories. In High Availability Business 'Best Practices' are of no use. Learn from mistakes others made for you.
My favorite: the company that took care of everything. 2 Data centres, half a mile apart. Dark fiber between the DC's. Data Guard in Max. Protection mode. UPS. Generator. Extra Fuel. At one beautiful day a forklift it a powerline, and half of Rotterdam went out of power. No worries though: UPS kicked in, Generator was started in time, evrything ran smoothly. For appr. 45 minutes. Then alarms started ringing. Temperatures in the DC's went sky high. It appeared someone forgot to take the airconditioning into account when calculating the power the Generator needed to deliver. Or they were simply not connected. Whatever, the CEO found himself removing batons from the windows, and carefully removing the panes in his 'highly secure' datacenter, to let fresh air come in. Just think problems. Find a problem for every solution......
Search the oracle-l archives. I posted on Data Guard 8 times this year and 42 times or so last year. Read documentation, it really isn't bad at all.

Apologies for not providing a full answer. I have loads of work on my desk. However, I think I gave you a strating point to discover the beautiful and challenging world of High Availability.

Best regards,

Carel-Jan Engel

===
If you think education is expensive, try ignorance. (Derek Bok) ===

On Mon, 2006-04-03 at 12:01 -0700, Jared Still wrote:

> Carel-Jan?
>
> Are you here?
>
> It is about dinner time in the Netherlands though.
>
> Jared
>
>
>
> On 4/3/06, Li Li <litanli_at_gmail.com> wrote:
>
> Hi, All,
>
> Anybody has used Oracle Data Guard before? What's your
> experiece with it? like it or dislike it? Any challenge? Any
> best practice?
>
> Thank you for your sharing!
> -Li
>
>
>
>

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