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Hi,

I have experience with HP-UX and its disk management, and I have experience
with MS-DOS like disk management (including Linux, of course). For the
Itanium Integrity servers however there seem to be MS-DOS like partitions with
UNIX-like nomenclature and tools.

I'm having problems with this, because it's neither meat (HP-UX) nor fish
(DOS). Setting up HP-UX on the Itanium gives me some problems: Can I have two
VGs on one large disk by creating two partitions that LVM will use? Is there
some whitepaper designed for those who are new to these HP-UX disk
partitioning concepts? (I've searched Instant Information without success;
"Partitions" are something very different there)

(I know what the disadvantages of two VGs on one disk are, but I'm hoping that
Ignite-UX' recovery tapes will be able to restore just that (system) partition
on the disk without touching the other VG (application data). Would it work?)

Regards,
Ulrich

Hello !

Ulrich Windl wrote:
> I have experience with HP-UX and its disk management, and I have experience
> with MS-DOS like disk management (including Linux, of course). For the
> Itanium Integrity servers however there seem to be MS-DOS like partitions with
> UNIX-like nomenclature and tools.
So far I know is on the IA64 one partition for the EFI (Bootloader), one
for the firmware, and a other partition for HPUX.

> I'm having problems with this, because it's neither meat (HP-UX) nor fish
> (DOS). Setting up HP-UX on the Itanium gives me some problems: Can I have two
> VGs on one large disk by creating two partitions that LVM will use? Is there
No. A disk (PV) under LVM can only be only in one Volume group.

> some whitepaper designed for those who are new to these HP-UX disk
> partitioning concepts? (I've searched Instant Information without success;
> "Partitions" are something very different there)
Have you looked at docs.hp.com or itrc.hp.com ?

> (I know what the disadvantages of two VGs on one disk are, but I'm hoping that
> Ignite-UX' recovery tapes will be able to restore just that (system) partition
> on the disk without touching the other VG (application data). Would it work?)
No, because two VGs on one PV it is not posible. Or do you mean, if the
EFI will be restored by ignite ?
Can you please explain more detailed, what you mean.

Regards

Lars

In article <df276e$409$1@windu.dotsch.de>, Lars Bausch wrote:
> Hello !
>
> Ulrich Windl wrote:
>> I have experience with HP-UX and its disk management, and I have experience
>> with MS-DOS like disk management (including Linux, of course). For the
>> Itanium Integrity servers however there seem to be MS-DOS like partitions with
>> UNIX-like nomenclature and tools.
> So far I know is on the IA64 one partition for the EFI (Bootloader), one
> for the firmware, and a other partition for HPUX.

And this cannot be changed?

>> I'm having problems with this, because it's neither meat (HP-UX) nor fish
>> (DOS). Setting up HP-UX on the Itanium gives me some problems: Can I have two
>> VGs on one large disk by creating two partitions that LVM will use? Is there
> No. A disk (PV) under LVM can only be only in one Volume group.

I think the definition of PV may be relevant here. I mean, the
bootloader and firmware areas aren't part of the PV, are they?

Would "disk slice" be a better term?

If you use, say, fdisk on Linux, to modify the disk partition table, can
you get two half-disk PVs even in HP-UX?

(Just to clarify: in Linux's LVM, you can. There you can define any
device, be it a whole-disk device or a slice, as the PV. And mirroring
is done by putting the PV on a metadevice that handles the mirroring -
or RAID5... Of course, Linux's LVM isn't supposed to be anything like
HP-UX's on the inside anyway, either.)

>> "Partitions" are something very different there)
> Have you looked at docs.hp.com or itrc.hp.com ?

I don't think they have much left on the relevant kind of partitions on
HP-UX ... (never seen a hard-partitioned disk on HP-UX myself but I've
read about it in an old manual.)

>> (I know what the disadvantages of two VGs on one disk are, but I'm hoping that
>> Ignite-UX' recovery tapes will be able to restore just that (system) partition
>> on the disk without touching the other VG (application data). Would it work?)
> No, because two VGs on one PV it is not posible. Or do you mean, if the
> EFI will be restored by ignite ?
> Can you please explain more detailed, what you mean.

I think he's trying to do it the Linux way, with PVs on slices instead
of on the whole disk.

Depends on how the disk handling is done there.

I haven't gotten my hands on an IA-64 box at all yet, but might in the
near future... and this does seem like a sensible question to me.


--
Mikko Nahkola <mnahkola@trein.ntc.nokia.com>
#include <disclaimer.h>
#Not speaking for my employer. No warranty. YMMV.

Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> wrote:
[deleted]
> (I know what the disadvantages of two VGs on one disk are, but I'm
> hoping that Ignite-UX' recovery tapes will be able to restore just
> that (system) partition on the disk without touching the other VG
> (application data). Would it work?)

Can't you just put the application data in its own LV(s)? If you keep
the recovery tapes up-to-date with any changes in the (vg00) LVM layout,
a restore should not touch the (application data) *LV(s)* in any way.
I.e. a vgcfgrestore(1M) of an *unchanged* VG does not touch any LVs in
that VG.

Lars Bausch <lars.bausch@dotsch.de> writes:

> Hello !
>
> Ulrich Windl wrote:
> > I have experience with HP-UX and its disk management, and I have experience
> > with MS-DOS like disk management (including Linux, of course). For the
> > Itanium Integrity servers however there seem to be MS-DOS like partitions with
> > UNIX-like nomenclature and tools.
> So far I know is on the IA64 one partition for the EFI (Bootloader), one for
> the firmware, and a other partition for HPUX.
>
> > I'm having problems with this, because it's neither meat (HP-UX) nor fish
> > (DOS). Setting up HP-UX on the Itanium gives me some problems: Can I have two
> > VGs on one large disk by creating two partitions that LVM will use? Is there
> No. A disk (PV) under LVM can only be only in one Volume group.
>
> > some whitepaper designed for those who are new to these HP-UX disk
> > partitioning concepts? (I've searched Instant Information without success;
> > "Partitions" are something very different there)
> Have you looked at docs.hp.com or itrc.hp.com ?
>
> > (I know what the disadvantages of two VGs on one disk are, but I'm hoping that
> > Ignite-UX' recovery tapes will be able to restore just that (system) partition
> > on the disk without touching the other VG (application data). Would it work?)
> No, because two VGs on one PV it is not posible. Or do you mean, if the EFI
> will be restored by ignite ?
> Can you please explain more detailed, what you mean.

Using "idisk" I created 4 partitions: 500MB EFI, 500MB HPSP, 40GB HPUX, 240GB
HPUX. However the Install Interface seems to do not care; it just offers to
install HPUX on a 280GB logical volume. The diagnostics CD refuses to install
the diagnostics into the HPSP partition saying there is none. This all seems
to overly complicated. What use is a partition table that is ignored?

Regards,
Ulrich

Frank Slootweg <this@ddress.is.invalid> writes:

> Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> wrote:
> [deleted]
> > (I know what the disadvantages of two VGs on one disk are, but I'm
> > hoping that Ignite-UX' recovery tapes will be able to restore just
> > that (system) partition on the disk without touching the other VG
> > (application data). Would it work?)
>
> Can't you just put the application data in its own LV(s)? If you keep
> the recovery tapes up-to-date with any changes in the (vg00) LVM layout,
> a restore should not touch the (application data) *LV(s)* in any way.

Hi,

well if HP-UX patches wouldn't make the systems unbootable from time to time,
and if recovery media really would be able to revive an unbootable system,
this would not be a problem at all. However I had had unbootable systems that
had to be recovered by installing the recovery tape. As this is downtime, you
try to keep that as short as possible. If you have all your application data
on its own VG (we are talking about a database application >50GB), then just
recover the root/boot VG, and then import the other VG, and all your
application data is untouched (the OS will lack most recent changes of
course). If you have all in one VG, recovering means you also have to recover
the database data which takes much longer to create a recovery media and to
restore it. In addition Ignite-UX does not support recovery media >4GB (no
double-layer DVD, no media change).

So I guessed that the LVM should only touch the device (e.g. partition instead
of whole disk) and having a PV in a partition (multiple PVs on one disk) would
work. This would assume recovery would not touch the partition table. This
also seems to be not true.


> I.e. a vgcfgrestore(1M) of an *unchanged* VG does not touch any LVs in
> that VG.

Yes, but the type of problem that can be fixed using vgcfgrestore is not the
type of problem I'm afraid of.

Regards,
Ulrich

Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> wrote:
> Frank Slootweg <this@ddress.is.invalid> writes:
>
> > Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> wrote:
> > [deleted]
> > > (I know what the disadvantages of two VGs on one disk are, but I'm
> > > hoping that Ignite-UX' recovery tapes will be able to restore just
> > > that (system) partition on the disk without touching the other VG
> > > (application data). Would it work?)
> >
> > Can't you just put the application data in its own LV(s)? If you
> > keep the recovery tapes up-to-date with any changes in the (vg00)
> > LVM layout, a restore should not touch the (application data)
> > *LV(s)* in any way.
>
> Hi,
>
> well if HP-UX patches wouldn't make the systems unbootable from time
> to time, and if recovery media really would be able to revive an
> unbootable system, this would not be a problem at all. However I had
> had unbootable systems that had to be recovered by installing the
> recovery tape. As this is downtime, you try to keep that as short as
> possible. If you have all your application data on its own VG (we are
> talking about a database application >50GB), then just recover the
> root/boot VG, and then import the other VG, and all your application
> data is untouched (the OS will lack most recent changes of course). If
> you have all in one VG, recovering means you also have to recover the
> database data which takes much longer to create a recovery media and
> to restore it. In addition Ignite-UX does not support recovery media
> >4GB (no double-layer DVD, no media change).

No, as I said, the recovery does not touch a LV/filesystem (in vg00)
if you do not include that filesystem in your recovery tape. So you do
not have to recover the database.

> So I guessed that the LVM should only touch the device (e.g. partition
> instead of whole disk) and having a PV in a partition (multiple PVs on
> one disk) would work. This would assume recovery would not touch the
> partition table. This also seems to be not true.
>
> > I.e. a vgcfgrestore(1M) of an *unchanged* VG does not touch any LVs
> > in that VG.
>
> Yes, but the type of problem that can be fixed using vgcfgrestore is
> not the type of problem I'm afraid of.

What I meant there is the vgcfgrestore which the (Ignite-UX) recovery
process does, not one which you do yourself. So, as far as your
application data LV/filesystem is concerned, it does not matter if the
recovery provess does a vgcfgrestore or not.