Re: Is it possible to achieve five 9's without using OPS ?

Frequency with which Oracle software is
upgraded ? Time it takes to apply an
upgrade ? Then factor in that OPS/RAC
do not allow rolling upgrades - the whole system has to come down and restart.

Personally I do not believe 99.999% is
possible - but it may well be a useful
target to focus the attention; and it
is notionally possible with 9.0 and
managed standby and a hell of a lot
of carefully designed infrastructure.

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Jonathan Lewis
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Bass Chorng wrote in message ...


>In your opinion about HA, is it possible to reach 5 9's

>(99.999% uptime or 5 minutes of down time per year)

>in an Oracle environment, without using OPS or 9iRAC ?

>

>I am only familiar with VCS, but I think it is the same

>regardless what you use as HA platform, that is, if it

>requires a database startup in the fail-over, then it is

>nearly impossible to reach 5 9's.

>

>Database startup on another node (basically from a shutdown

>abort of the original node) to my experience could take over

>5 minutes alone. HW failures on a large system are usually

>more than once a year.

>

>Replication tools in the market don't give you real time

>sync. Even if they do, the multiple point of failures and

>performance problem present a bigger issue.

>

>I really can't think of a better way than 9iRAC. But I like

>to hear your opinion.

>

>Thanks.