Boot disks in SAN

[Emilio Brusa]

Although you can have the boot disks inside the SAN,I would prefer to boot from internal disks. because the SAN could have depending of your configuration more points of failure.
Before choice SAN you should revise your San enviroment to see the possible points of failure. (switch,disk,etc..)

E.

[Zinky]

Well we will possibly be "brave" enough to proceeed since we have a redundant SAN... Half the SAN components, HBA's, Cabling, Core Switches can be allowed to fail. Of course Disk arrays are not supposed to Fail ;-)

[Uwe Zessin]

Just don't tell that the disk arrays ;-)

[Fabio Ettore]

Good morning guys.

Nelson,
I agree with you about redundanted environment. Of course with good attention boot disks in SAN is possibile and it works.
Even, from your words and descriptions, it seems that boot disks in SAN is better than boot disks inside the machine!
Really do you think this?

Altogether I agree with Uwe about his first post. He talked about Tru64; Trucluster on Tru64 (and maybe in future on HP-UX!) works in a way that all disks are shared (boot disks too). That is a functionality of Trucluster and (of course) is not a problem to share boot disks (even about that I can be critic!).
But on HP-UX Service Guard just shares data disks.
Definitively I think that it is not a good idea to configure boot disks in SAN (thus shared boot disks). Even redundanted environment has too many points of failure. Also (not as last) the thought that anyone handles Disk Array (for example to configure volume groups on other HP-UX systems attached to Disk Array) can harm my boot disks.

The only one advantage to configure boot disks in SAN is economic side. Is it worth to do that?

Best regards,
Ettore

[Uwe Zessin]

Ettore,

OpenVMS and Tru64 Unix require a separate license to enable mirroring. It is just a question if you buy a license for each server -or- a separate backplane RAID controller to mirror your boot disks -or- use the mirror functionality of your SAN-based storage array that you already have paid for.

How is this on HP-UX? I can't really say I have experience with it, but following the forums it sounds like LVM is 'standard'.


Allow me a small correction? OpenVMS allows booting multiple cluster memebers from one single shared system disk per hardware architecture - in a Tru64 Unix cluster each member needs a small boot disk containing the kernel and configuration data, the remainder it then on one common disk.

[Fabio Ettore]

Uwe,

yes, LVM is standard, mirror needs a license on HP-UX too.

Thanks for your explanation about OpenVMS and Tru64; corrections/clarifications always are welcome! :-)

Best regards,
Ettore

[Emilio Brusa]

Ettore.
The new machines like rp8420,rp3410 with enterpise OE, include the mirror license now.

E.

[Fabio Ettore]

Hi Emilio,

are you sure about that?
I think that mirror license has to be purchased apart. If you have a machine where mirror is already installed (with license) then I think that HP configured it for you but normally it is not so.

Otherwise can you provide a document or anything to sustain your information?

Thanks and best regards,
Ettore

[Zinky]

HPUX Enterprise OE includes:

Online JFS (aka Full VxFS)
GlancePlus Pak
HPOV Performance Agents (aka MeasureWare)
MirrorDisk/UX

Plus of course the base Veritas Volume Manager 3.5m -- that comes with Free Mirroring but only on rootDG.

But if your Bootdisk (on a SAN) is already a protected LUN (ie. RAID5 or RAID10 on your SAN Array) -- why bother with MirrorDisk/UX?

[Fabio Ettore]

Hi everybody,

it is important to clear all things:

Emilio,
you said:
>The new machines like rp8420,rp3410 with enterpise OE, include the mirror license now.

It is exact for an half: MirrorDisk/UX is bundled (of course with license) in OS HP-UX Enterprise OE for the version 11.11.
Anyway MirrorDisk/UX doesn't depend on model of machine (like rp8420,rp3410).
Then if you say that

'The new machines like rp8420,rp3410 with enterpise OE, include the mirror license now.'

it is important to specify the version of HP-UX and (of course) Operating Environment.


Nelson,
question was submitted from Uwe. It is not about my problem. You can find the question of Uwe above.
Anyway when you said

'HPUX Enterprise OE includes:

Online JFS (aka Full VxFS)
GlancePlus Pak
HPOV Performance Agents (aka MeasureWare)
MirrorDisk/UX'

it is right as for Emilio but it is the truth for HP-UX 11.11 no 11.00.
Also: MirrorDisk/UX is bundled in that Operating Environment, that is Enterprise OE, not in other OEs. Infact in 11.11 was introduced a new hierarchy of Operating Environment (the following is valid for servers):

HP-UX 11i Base OE

HP-UX 11i Internet OE, bundled with it:
°Unlimited user licenses,Web QoS,JavaVM,Apache websvr,E-speak,Ignite-UX,All networking drivers,EMS,LDAP.

HP-UX 11i Enterprise OE, it is Internet OE plus the following applications:
°PRM,MirrorDisk/UX,OnLineJFS,GlancePlus,HA Monitors.

HP-UX 11i Mission Critical OE, it is Enterprise and Internet OEs plus the following applications:
°MC/ServiceGuard,WLM


CONCLUSION:
MirrorDisk/UX with its license is included in HP-UX 11i Enterprise OE or higher OE, no in base or Internet OE.

Therefore your affirmations are good for an half because it is important to specify which HP-UX version and which Operating Environment we are talking about.

Hope this clarifies all doubts.
Welcome will be other informations.

Best regards,