Re: SSA disk sharing

From: Mark Lamport (lamport_at_CS.KCMETRO.EDU)
Date: 06/23/04

  • Next message: Kumar, Praveen (cahoot): "ftp problem" 
    Date:         Wed, 23 Jun 2004 06:33:39 -0600
To: aix-l@Princeton.EDU

    Would there be any problem having one drawer of 7133 D40 configured as a
    raid 10 array and connected to 6230 SSA adapters on our production and
    development servers. The raid 10 array would then be one logical hdisk and
    I would create a vg just for that logical disk. I would run rman backups
    which would use a filesystem on this logical disk. After backups are
    finished I would exportvg on production and importvg on the development
    server. Then I could refresh development databases with a copy of
    production databases using the rman backup files. After databases are
    refreshed exportvg from development and importvg back on production. Any
    problems with this?

    thanks.

    Mark Lamport

    ----- Original Message -----
    From: "Coonfield, Ben" <bcoonfield@TMH.TMC.EDU>
    Newsgroups: bit.listserv.aix-l
    To: <aix-l@Princeton.EDU>
    Sent: Monday, June 21, 2004 9:33 AM
    Subject: Re: SSA disk sharing

    > Yep, you can define a concurrent volume group that is simultaneously
    > accessible to both systems. This is what you would be doing, if you were
    > using Oracle raw disks.
    >
    > What you can't do is define a JFS file system on such a volume group. AIX
    > supports sharing the devices, but JFS doesn't support sharing the file
    > system.
    >
    > -----Original Message-----
    > From: IBM AIX Discussion List [mailto:aix-l@Princeton.EDU]On Behalf Of
    > Mark Lamport
    > Sent: Monday, June 21, 2004 11:16 AM
    > To: aix-l@Princeton.EDU
    > Subject: Re: SSA disk sharing
    >
    >
    > Well, what I am reading leads me to believe it can be done;
    >
    > SSA Disk Concurrent Mode of Operation Interface
    > The SSA subsystem supports the ability to broadcast one-byte message codes
    > from one host to all other hosts connected to the same disk drive. This
    > message-passing capability can be used to synchronize access to the disk
    > drive. The operating system has a concurrent mode interface to use this
    > hardware functionality.
    >
    > The concurrent mode of operation requires that a top kernel extension runs
    > on all hosts sharing a disk drive. The top kernel extensions communicate
    > with each other via the SSA subsystem using the concurrent mode interface
    of
    > the SSA disk device driver. This interface allows a top kernel extension
    to
    > send and receive messages between hosts.
    >
    > The concurrent mode interface consists of an entry point in both the SSA
    > disk device driver and the top kernel extension. Two ioctls register and
    > unregister the top kernel extension with the SSA disk device driver. The
    SSA
    > disk device driver's entry point provides the means to send messages as
    well
    > as lock, unlock, and test disk drive. The top kernel extension entry point
    > processes interrupts, including receiving messages from other hosts.
    >
    > Note: In order for the concurrent mode interface to work, the
    node_number
    > attribute of the ssar router must be set to a different, non zero, value
    on
    > each of the hosts sharing a disk drive. After the node_number has been
    > assigned, the host must be rebooted for it to take effect.
    > ----- Original Message -----
    > From: "Coonfield, Ben" <bcoonfield@TMH.TMC.EDU>
    > Newsgroups: bit.listserv.aix-l
    > To: <aix-l@Princeton.EDU>
    > Sent: Monday, June 21, 2004 8:57 AM
    > Subject: Re: SSA disk sharing
    >
    >
    > > Is Oracle using raw disks or file systems? Assuming file systems, then
    I
    > > don't think there is any way for the same disks to be simultaneously
    > > available to both systems. What you can do is define a volume group to
    > both
    > > systems, so that it can be varied online on either, but not on both at
    the
    > > same time. Which ever system currently owns the VG will have full
    access,
    > > including update if you wish. This works well for failover, but it
    sounds
    > > like it won't provide the true concurrent access you are probably
    looking
    > > for.
    > >
    > > If you are using raw disks, I think what you want can probably be done.
    > In
    > > this it would be set up so that both systems had full access at the same
    > > time as far as AIX is concerned. Locking between the two Oracle
    instances
    > > if any would be done by Oracle.
    > >
    > > -----Original Message-----
    > > From: IBM AIX Discussion List [mailto:aix-l@Princeton.EDU]On Behalf Of
    > > Mark Lamport
    > > Sent: Monday, June 21, 2004 9:31 AM
    > > To: aix-l@Princeton.EDU
    > > Subject: SSA disk sharing
    > >
    > >
    > > I want my development server to be able to read my production server
    > Oracle
    > > Rman backup files on SSA disk. I know how to set up the hardware but I
    > > don't what needs to be setup the software.
    > > On the mainframe when I have done this there are lock files. What needs
    > to
    > > be done on AIX 5.2. I want the development access to be read only.
    > >
    > > thanks.
    > >
    > > Mark Lamport
    > >
    > > -----------------------------------------
    > >
    >
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  • Next message: Kumar, Praveen (cahoot): "ftp problem"

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