Re: active/passive with multiple instances

Minor points of contention:

An Active/Passive cluster is always called that and never Passive/Active. So
it never get confusing.

A SQL DBA should care that SQL run on a cluster, they have options of moving
the group so that SQL can stay up while the OS gets worked on. This is not
an option without clustering.

There is only 1 SQL Server per instance :) Just so other don't get confused.

You can not apply a SQL Server hotfix without it going down, and OS hotfix
is completely different.

It does matter about the hardware, to achieve true HA it needs to happen at
every level of the organization.

Cheers,

Rod

MVP - Windows Server - Clustering
http://www.nw-america.com - Clustering Website
http://msmvps.com/clustering - Blog
http://www.clusterhelp.com - Cluster Training

"Michael Hotek" <mike@xxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:O22UR0fFGHA.216@xxxxxxxxxxxxxxxxxxxxxxx
> It is simply a matter of this. A SQL Server DBA doesn't care about where
> a SQL Server is physically running. It is running within a cluster. The
> physical presence on a machine is completely transient in nature And that
> transience in time is quite literally up to whim.
>
> If you are using that terminology, what was an Active/Passive cluster
> right now is all of a sudden a Passive/Active cluster 1 minute for now.
> It gets even more confusing when you start adding additional nodes.
>
> Put quite simply, once the Windows cluster has been installed and is
> functioning, a SQL Server DBA plain and simply doesn't care about it being
> in a cluster. By that I mean, the cluster becomes their hardware platform
> instead of a physical machine. By looking at it from that perspective
> which is what the single instance/multi-instance terminology does, it
> eliminates a lot of confusion particularly in the following areas:
> 1. You can NOT apply a service pack without the SQL Server going offline,
> because while it may be in a cluster, there is still only 1 SQL Server
> 2. You can not apply a hot fix without the SQL Server going offline,
> because while it may be in a cluster, there is still only 1 SQL Server
> 3. All of this gobbledygook that everyone keeps wanting to talk about
> within clustering about balancing memory, processors, I/O, etc. has
> absolutely nothing to do with clustering. It has everything to do with
> installing multiple instances of SQL Server on a hardware platform
>
> When you come to the realization that it really doesn't matter how many
> pieces of physical hardware are in the platform you are working against
> and that it is still just a SQL Server running on a single hardware
> platform, this whole notion of a virtual resource goes away. You are left
> with basically a server that comes with its own robot. That robot watches
> over the server and when a piece of hardware fails, it automatically shuts
> everything down, replaces the hardware, and brings everything back online.
> The SQL Server DBA gets all of that for free and simply installs and
> manages their SQL Servers that are running on that hardware platform.
>
> --
> Mike
> Mentor
> Solid Quality Learning
> http://www.solidqualitylearning.com
>
>
> "Rodney R. Fournier [MVP]" <rod@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
> message news:OO5oaEfFGHA.3900@xxxxxxxxxxxxxxxxxxxxxxx
>>I guess it all boils down to what a true DBA/SQL Guru knows/believes
>>(Geoff) and a computer hacks knows (Me). Since I have only seen you wrong
>>once in the last few years, I will take the back seat here and let you
>>drive :)
>>
>> Cheers,
>>
>> Rod
>>
>> MVP - Windows Server - Clustering
>> http://www.nw-america.com - Clustering Website
>> http://www.msmvps.com/clustering - Blog
>> http://www.clusterhelp.com - Cluster Training
>>
>>
>> "Geoff N. Hiten" <SQLCraftsman@xxxxxxxxx> wrote in message
>> news:ut09M2eFGHA.3036@xxxxxxxxxxxxxxxxxxxxxxx
>>> Despite my earlier jab, I am siding with Mike. Active-Active-P-A-...
>>> just invites misunderstanding. New users expect clustering to be a
>>> scale out technology based on this nomenclature. Explaining that it
>>> isn't and why becomes discouraging. Single- and Multi-instance
>>> describes the cluster's basic functionality, something that no
>>> combination of Active and Passive does.
>>>
>>> --
>>> Geoff N. Hiten
>>> Senior Database Administrator
>>> Microsoft SQL Server MVP
>>>
>>>
>>>
>>>
>>>
>>> "Rodney R. Fournier [MVP]" <rod@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
>>> message news:%237mHGGaFGHA.1124@xxxxxxxxxxxxxxxxxxxxxxx
>>>> Personally I hate the term, sorry Mike. I like A/A much better. For
>>>> example, here at work we have a multi instance cluster. That does not
>>>> tell you anything, now if I said it was A/A/P would you guess it's a 3
>>>> node cluster with 2 or more instances?
>>>>
>>>> Cheers,
>>>>
>>>> Rod
>>>>
>>>> MVP - Windows Server - Clustering
>>>> http://www.nw-america.com - Clustering Website
>>>> http://www.msmvps.com/clustering - Blog
>>>> http://www.clusterhelp.com - Cluster Training
>>>>
>>>>
>>>> "Kevin3NF" <Kevin@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
>>>> news:e3rstAaFGHA.140@xxxxxxxxxxxxxxxxxxxxxxx
>>>>> Yes...you are correct...but to date I have not heard anyone outside of
>>>>> academia and Microsoft fora use
>>>>> multi-instance. When they say Active/Active, we all know what they
>>>>> mean :-)
>>>>>
>>>>> Sorry to have pushed your terminology button Mike :-)
>>>>>
>>>>> --
>>>>> Kevin Hill
>>>>> 3NF Consulting
>>>>> www.3nf-inc.com/NewsGroups.htm
>>>>>
>>>>>
>>>>>
>>>>> "Michael Hotek" <mike@xxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
>>>>> news:ueVAb99EGHA.648@xxxxxxxxxxxxxxxxxxxxxxx
>>>>>> No, thus leaving your cluster as a multi-instance cluster. There is
>>>>>> absolutely, no such thing as an active/active or active/passive SQL
>>>>>> Server cluster. Such a thing does not exist at all.
>>>>>>
>>>>>> --
>>>>>> Mike
>>>>>> Mentor
>>>>>> Solid Quality Learning
>>>>>> http://www.solidqualitylearning.com
>>>>>>
>>>>>>
>>>>>> "Kevin3NF" <Kevin@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
>>>>>> news:eV5VIU9EGHA.1464@xxxxxxxxxxxxxxxxxxxxxxx
>>>>>>> Thus turning your cluster into active/active :-D
>>>>>>>
>>>>>>> --
>>>>>>> Kevin Hill
>>>>>>> 3NF Consulting
>>>>>>> www.3nf-inc.com/NewsGroups.htm
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> "Geoff N. Hiten" <SQLCraftsman@xxxxxxxxx> wrote in message
>>>>>>> news:O9cbhWzBGHA.3528@xxxxxxxxxxxxxxxxxxxxxxx
>>>>>>>> Nope. Each instance has its own resource dependency list. If a
>>>>>>>> resource that is unique for a single instance times out, it will
>>>>>>>> trip that instance only for failover.
>>>>>>>>
>>>>>>>> --
>>>>>>>> Geoff N. Hiten
>>>>>>>> Senior Database Administrator
>>>>>>>> Microsoft SQL Server MVP
>>>>>>>>
>>>>>>>>
>>>>>>>> "ronc" <ronc@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
>>>>>>>> news:9232DBCF-60C1-4A35-9A96-53594E2BC504@xxxxxxxxxxxxxxxx
>>>>>>>>> Our production enviornment consists of 2 production servers in an
>>>>>>>>> active\passive set up. The production enviornment has 3
>>>>>>>>> instances. Is it
>>>>>>>>> possible that a single instance can fail over to the standby node
>>>>>>>>> and leaving
>>>>>>>>> the other 2 behind? We think this is happeing but I thought if
>>>>>>>>> the server
>>>>>>>>> fails over to the passive server then it would include all 3
>>>>>>>>> instances (All
>>>>>>>>> or nothing)
>>>>>>>>>
>>>>>>>>> Thanks
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
>
>


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