Re: SRDF/A failover.
From: <matthias.hoys_at_gmail.com>
Date: Thu, 19 Feb 2009 06:10:34 -0800 (PST)
Message-ID: <5eeb3893-5e51-4dde-b51f-c921feb15546_at_k8g2000yqn.googlegroups.com>
On Feb 19, 2:05 am, shweta.kapar..._at_googlemail.com wrote:
> On Feb 19, 12:42 am, hpuxrac <johnbhur..._at_sbcglobal.net> wrote:
>
>
>
> > On Feb 18, 6:33 pm, shweta.kapar..._at_googlemail.com wrote:
>
> > > Hi All
>
> > > We have site -A (Live) and site-B (Disaster Recovery).
>
> > > Database is replicated to site-B using EMC SRDF/A links.
>
> > > We use Veritas global cluster manager to monitor/control the failover.
>
> > > Global failover is set to manual not automatic. i.e. Manually DNS
> > > entries has to be updated. so that services can be pointed towards the
> > > surviving site.
>
> > > To start the databases at site-B ( DR site)
> > > 1. SRDFA links should be made split.
> > > 2. After (1) above database is started at DR site.
>
> > > Question:
> > > a) What if site -A ( live) is operational and site-B( DR) is in sync
> > > with site-A through SRDFA links.
> > > Next if accidently databases at DR site are started without
> > > splitting the SRDFA links, does that will dismount
> > > the SAN file system at site-A( live) and hence bring down the
> > > live databases?
>
> > > Regards
>
> > > Shweta.
>
> > The DR site should not be read/writeable until the links are split.
> > Read the EMC white papers on Oracle SRDFA ...- Hide quoted text -
>
> > - Show quoted text -
>
> Thanks for the prompt reply.
> Agreed> The DR site should not be read/writeable until the links are split.
>
> But what if
> DR site is read/waiteable without links are split...
>
> In such a scenario - Both site becomes read/writeable so will that
> make site-A ( in our example..) down.?
>
Date: Thu, 19 Feb 2009 06:10:34 -0800 (PST)
Message-ID: <5eeb3893-5e51-4dde-b51f-c921feb15546_at_k8g2000yqn.googlegroups.com>
On Feb 19, 2:05 am, shweta.kapar..._at_googlemail.com wrote:
> On Feb 19, 12:42 am, hpuxrac <johnbhur..._at_sbcglobal.net> wrote:
>
>
>
> > On Feb 18, 6:33 pm, shweta.kapar..._at_googlemail.com wrote:
>
> > > Hi All
>
> > > We have site -A (Live) and site-B (Disaster Recovery).
>
> > > Database is replicated to site-B using EMC SRDF/A links.
>
> > > We use Veritas global cluster manager to monitor/control the failover.
>
> > > Global failover is set to manual not automatic. i.e. Manually DNS
> > > entries has to be updated. so that services can be pointed towards the
> > > surviving site.
>
> > > To start the databases at site-B ( DR site)
> > > 1. SRDFA links should be made split.
> > > 2. After (1) above database is started at DR site.
>
> > > Question:
> > > a) What if site -A ( live) is operational and site-B( DR) is in sync
> > > with site-A through SRDFA links.
> > > Next if accidently databases at DR site are started without
> > > splitting the SRDFA links, does that will dismount
> > > the SAN file system at site-A( live) and hence bring down the
> > > live databases?
>
> > > Regards
>
> > > Shweta.
>
> > The DR site should not be read/writeable until the links are split.
> > Read the EMC white papers on Oracle SRDFA ...- Hide quoted text -
>
> > - Show quoted text -
>
> Thanks for the prompt reply.
> Agreed> The DR site should not be read/writeable until the links are split.
>
> But what if
> DR site is read/waiteable without links are split...
>
> In such a scenario - Both site becomes read/writeable so will that
> make site-A ( in our example..) down.?
>
What operating system are you using ? In AIX for example, a lock is held on a volume group by one host so another host that should see the same volumes can't mount it.
Matthias Received on Thu Feb 19 2009 - 08:10:34 CST