Re: multipath slvm hp-ux 11.23 - asm or raw??

From: Ujang Jaenudin <ujang.jaenudin_at_gmail.com>
Date: Tue, 12 Feb 2008 08:29:47 +0700
Message-ID: <3edcb66e0802111729i3c55ba22o9b56e3de76648889@mail.gmail.com>

sve,

the little conflict now going on between me and hp :)

The final configuration on the machine is:

1. each machine has 2 HBA
2. raw LVM configured with pvlink on both nodes
3. OCR & voting disk are placed on that raw LVM
4. oracle datafiles put on ASM (disk which formed asm comes from

LUN/disk devices)

    I created script for manual failover in case 1 HBA failure.

5. no service guard at all.
6. sadly HP said that activate raw LVM on 2 nodes is not supported :(
7. for that kind of configuration HP service guard should be in place - HP
8. I got confirmation from metalink that the above configuration is

fully supported
9. anyone has the same configuration? please share for the future problem :)

regards
ujang

On Feb 5, 2008 5:25 PM, Svetoslav Gyurov <softice_at_gmail.com> wrote:
>
> Hi,
>
> Sorry for the late reply. Well I don't have experience running Oracle RAC
> without SG, but I know installations which are running without SG, using
> physical raw disks and the cluster is running without any problems. The
> performance should be the same, in both cases you are using raw devices.
> About stability and management using SG is better by the reasons I said in
> the previous mail.
>
> Regards,
> sve
>
>
>
>
> Ujang Jaenudin wrote:
> svetoslav,
>
> thanks for the details,
> you are correct that crs 10g didn't state that we must use slvm.
>
> for this...
> "> ............ snip ......
>
>
> you can use disks device files as well, BUT first
> there is no guarantee that the names of the devices files will be the
> same at all nodes and second if someone decide to execute pvcreate at
> some of these files there is no warning message and all your data will
> be gone."
>
> how about the experiences about it? stability? performance?
> and all over pros & cons?
>
> I really want to use this kind of solution, due to service guard license.
>
> regards
> ujang
>
> On Feb 1, 2008 4:20 PM, Svetoslav Gyurov <softice_at_gmail.com> wrote:
>
>
> Hi Ujang,
>
> From Oracle 10g and appearing of Cluster Ready Services it is not
> necessary to use SLVM, you can use disks device files as well, BUT first
> there is no guarantee that the names of the devices files will be the
> same at all nodes and second if someone decide to execute pvcreate at
> some of these files there is no warning message and all your data will
> be gone.
>
> About your questions:
> 1. If you want to use SLVM you need to use Service Guard and Service
> Guard Extension for RAC.
> 2. LVM natively have alternate links which offers you failover and not
> load balancing if this is what you called multipath. Better way to have
> real multipath (load balancing and failover) is to use Secure Path
> depending of the mode of the storage (Active-Passive or Active-Active)
> and this is for HP-UX 11iv2 (HP-UX 11iv3 does have native multipath for
> AA mode).
> 3. Yes, I think it is good idea. Depends if you use SLVM then your can
> use ASM over SLVM raw device and yes you have at least better management.
> 4. Yes, it used to be impossible, but before two years HP released
> Service Guard Extension for RAC 11.17 which offered new functionality
> called SNOR (Single Node Online Reconfiguration), it is also available
> as a patch. Actually this new feature gives you the ability to shutdown
> all the nodes in the cluster but one and then on this particular node
> you can change the mode of the volume group without deactivating it,
> make the appropriate changes, propagate the change to the other nodes,
> move the volume group back to shared mode and then activate it at all
> other nodes. For more information please read:
> http://www.docs.hp.com/en/7389/LVM_SNOR_whitepaper.pdf
> 5. In the concepts of HP-UX this is called APA (auto port aggregation),
> bonding is on Linux and timing is on Windows. Actually Service Guard
> cannot aggregate ports, but can failover NICs by configuring and using
> standby network interfaces i.e. your Service Guard is using lan0 for
> HEARTBEAT and lan1 is standby network for interface lan0. So in case of
> failure of lan0, Service Guard will automatically bring lan1 online and
> try to resume the connection to the other node(s) through this interface.
>
> My personal opinion is to use SLVM over SGeRAC for several reasons:
> 1. Control - SG is flexible and offers better control. By using raw
> device files once the machine boots the Cluster Ready Services are
> started immediately and you have less control.
> 2. Identical logical volume names on all nodes on the cluster and naming
> convention
> 3. Some kind of protection - accidentally doing pvcreate will be refuser
> because the device is already initialized
> 4. Last but not at least Service Guard support for the SGeRAC Toolkit
> giving you integration between SGeRAC and Oracle10g stack. Better
> control by using multinode packages, package dependencies, cluster
> interconnect subnet monitoring and several other good features.
>
> Hope it helps.
>
> --
> sve
>
>
>
> Ujang Jaenudin wrote:
>
>
> all,
>
> I have itanium machine and hp-ux 11.23 installed, with 2 hba for each
> machine.
> I plan to use Shared LVM - raw.
>
> - I plan to not use serviceguard
> - is shared LVM natively support multipath (i means there is no
> multipath software from storage)
> - is it good idea to use ASM on top of shared LVM raw device?? - i
> thinking of easy management...
> i heard on shared LVM could not doing online changes.....
> - is NIC bonding/teaming can be configured without serviceguard??
>
> thanks for the sharing....
>
>
>
>

-- 
regards
ujang

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Received on Mon Feb 11 2008 - 19:29:47 CST