Re: Veritas storage foundation HA for windows

From: todd harrington (harrington_at_discussions.microsoft.com)
Date: 01/19/05 

Date: Wed, 19 Jan 2005 08:05:07 -0800

Hi Mike,

Thanks for the reply. How about Veritas Storage Foundation "HA" for Windows?
Are you familar with this "HA" version? The data*** claims "immediate"
failover (see excerpt below:

"If one of the servers or resources running on the server in a cluster
becomes unavailable as a result of failure or maintenance, another server
immediately begins providing service, a process known as failover."

My question is with this HA version and/or any SQL server options that
Veritas has... Does Veritas have an offering that does NOT require
application re-write? And is the failover time going to be any quicker than
Microsoft/SQL clustering? I am not sure what you get with Veritas that you
don't get with basic Windows 2003/SQL clustering.

Thanks,
Todd

"Mike Epprecht (SQL MVP)" wrote:

> Hi
>
> Veritas "Storage Foundation" is a data solution. It includes Volume Manager,
> which is just a SAN LUN to OS Volume mapping driver (We use it at work).
> This is a solution to manage your data, not the services like SQL Server.
>
> To make an application cluster suitable ("cluster aware" is for used for
> software running on a cluster), you just need to have you error handler
> re-try a connection a number of times when the connection drops. A
> no-brainer if an application is written correctly.
>
> Most of the time that we have hardware failure, the failure causes
> corruption of data. RAID controllers go bad, write junk and even the best
> cluster is screwed. No matter what HA solution you use, you are still
> limited to what the weakest component can do to your system.
>
> Hope you have multiple generators, multiple UPS's, multiple switches,
> multiple SANs, multiple ...well of everything.
>
> Whatever you use, test it for a good period of time. You might find that
> what you though was bullet proof has worse uptime than a single server.
>
> Regards
> --------------------------------
> Mike Epprecht, Microsoft SQL Server MVP
> Zurich, Switzerland
>
> IM: mike@epprecht.net
>
> MVP Program: http://www.microsoft.com/mvp
>
> Blog: http://www.msmvps.com/epprecht/
>
> "Todd" <Todd@discussions.microsoft.com> wrote in message
> news:739E7C9C-D30A-4D2A-940F-64823F32F757@microsoft.com...
> > Hi Mike,
> >
> > Thanks for the reply. We are mostly worried about HW failure. We do not
> have
> > time to re-write the application and the down time has to be 0 (or almost
> > zero).
> >
> > Has anyone used this product from Veritas. They claim "immediate"
> failover.
> > I am looking to find out if someone could tell me how it works (i.e. is
> > application re-write required and what is the down time for the failover).
> >
> > Thanks,
> > Todd
> >
> > "Mike Epprecht (SQL MVP)" wrote:
> >
> > > Hi
> > >
> > > As soon as SQL Server has to be shut down and start up (used by all
> > > clustering / HA availability solutions), you need to re-connect.
> > >
> > > SQL Server 2005 will have database mirroring, resulting in the MDAC
> stack
> > > doing the re-direction to the new machine, with about 5 second downtime.
> > >
> > > Trying 100% uptime with an application that does not support it is
> really
> > > throwing money at a bad problem.
> > >
> > > What is your biggest worry? Hardware, OS or SQL server failure causing
> you
> > > downtime?
> > >
> > > Regards
> > > --------------------------------
> > > Mike Epprecht, Microsoft SQL Server MVP
> > > Zurich, Switzerland
> > >
> > > IM: mike@epprecht.net
> > >
> > > MVP Program: http://www.microsoft.com/mvp
> > >
> > > Blog: http://www.msmvps.com/epprecht/
> > >
> > > "Todd" <Todd@discussions.microsoft.com> wrote in message
> > > news:5E827336-E5B3-4FBA-9FFB-2A9B386C237D@microsoft.com...
> > > > Hi,
> > > >
> > > > We have been looking at Stratus and Marathon Technologies for High
> > > > Availability solutions for SQL Server. Zero time is a requirement as
> well
> > > as
> > > > not having to make our application "cluster-aware". Microsoft
> Clustering
> > > > requires application modifications and almost 2 minutes of downtime
> for
> > > the
> > > > failover to happen.
> > > >
> > > > There is a product out on the market called: "Veritas storage
> foundation
> > > HA
> > > > for windows". Does this product allow for zero application down time
> and
> > > and
> > > > no application rewrite? Is this an alternative to a Stratus box or a
> > > Marathon
> > > > Technolgoes solution for HA?
> > > >
> > > > If someone could get back to me tonight it would be appreciated.
> > > >
> > > > Thanks,
> > > > Todd
> > >
> > >
> > >
>
>
>