vxvm hpux mechanism

 
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martin_215
Frequent Advisor

vxvm hpux mechanism

Im a solaris guy and recently ventured into hpux
Im trying to figure out how veritas vol manager works with hpux
in solaris its straightforward .uhve slices 3 and 4 for private and public region and can be accessed using /dev/dsk devices
and each slice has a special tag for identification

but for hpux there is only one device /dev/dsk/c0t0d0
and no special tag or device file
so how does vxvm identify the private region and public region on hpux?
6 REPLIES 6
Sanjay_6
Honored Contributor

Re: vxvm hpux mechanism

Hi Martin,

Take a look at the doc links below.

http://docs.hp.com/en/oshpux11ieoe.html#VERITAS%20Volume%20Manager%20and%20File%20System

Hope this helps.

Regds
bhavin asokan
Honored Contributor
Solution

Re: vxvm hpux mechanism

hi,

see the attachment.

regds,
martin_215
Frequent Advisor

Re: vxvm hpux mechanism

bhavin -the attachment you had sent is quite good
but i culdnt find it from docs.hp.com or anywhere else
i was looking to get the full document if its not hp internal
thankyou

Patrick Wallek
Honored Contributor

Re: vxvm hpux mechanism

If I am not mistaken, the document the Bhavin attached is a chapter from the Software Recovery Handbook which is available here:
http://www2.itrc.hp.com/service/iv/node.do?node=prodITRC%2FWW_Start%2FN1%7C16

There is only the one chapter on VxVM. But there is quite a bit of documentation available on VxVM on docs.hp.com at this link:
http://docs.hp.com/en/oshpux11ioe.html#VERITAS%20Volume%20Manager%20and%20File%20System

Now just to make sure we understand you completely, you are using the full VxVM and not the basic including LVM with vxfs file system right?
martin_215
Frequent Advisor

Re: vxvm hpux mechanism

im using the full VXVM
infact wat i m looking is the mechanism of accessing private and public region.
comparing solaris to hpux and see how hpux figure out private and pub region.

this is how it works in solaris:-

/dev/dsk/c0t0d0s3 and /dev/dsk/c0t0d0s4 is private and pub region and they have partition tags as 14 and 13 in partition table.so vxvm daemon scan the disk ,find this partition and access the private region with /dev/dsk/c0t0d0s3
once it get access to private region it knows how to find all the datastructures to get the diskgroup up and running

now take hpux
it doesnt have any specific tag nor does it have specific slices for private and pub region
all it has is a single /dev/dsk/c0t0d0

so i belive unlike solaris vxvm, hpux vxvm has little flexibility as far as storing private region.it might always be located in the initial 2MB or something.

so the vxvm daemons might be scanning /dev/dsk/c0t0d0 and read a specific number of sectors into memory which it know would contain private region information.

solaris vxvm can have private region stored anywhere in the disk.only thing is it wuld mark the partition with a specific partition TAG

correct me if I am wrong on how hpux vxvm works....


thanks gurus for the links
Patrick Wallek
Honored Contributor

Re: vxvm hpux mechanism

You are correct in that HP-UX does not use slices, except with the boot disk on Itanium machines, but that's a different story.

For info on the public/private regions on VxVM disks, have a look at pages 55-56 in the following manual(Veritas Volume Manger 3.5 Administrators Guide - Chapter 2: Administering Disks):
http://docs.hp.com/en/5187-1369/5187-1369.pdf