LVM procedures

[Marco A.]

Hello,

I'm trying to find some documentation about LVM on arrays/storage devices.

All documents, links, etc, are really appreciated.

I want to know about LVM on external drives/Storage. EMC, etc.

Best regards,

Marco

[Patrick Wallek · Accepted solution]

LVM does not behave any differently on external storage vs. internal storage. You use the same commands and create your VG's and LV's exactly the same way.

What is it you REALLY want to know? A more detailed question will lead to a more detailed answer.

[Torsten.]

Up to 11.23:

http://docs.hp.com/en/oshpux11iv2.html#LVM%20Volume%20Manager

11.31:

http://docs.hp.com/en/oshpux11iv3.html#LVM%20Volume%20Manager

Some array vendors (HP too) have special software for multipathing.

[Marco A.]

ok ok , Let's say that I want to move the config from one server to another, using the same external storage.

In addition, there're some procedures when trying to add more space, you could do it from the SAN, or from the server, but any of those have different considerations.

Best regards,

Marco

[Patrick Wallek]

>>Let's say that I want to move the config from
>>one server to another, using the same
>>external storage.

In this case you would export the VG's on one server and import them on another. Have a look at the 'vgexport' and 'vgimport' man pages for details on the commands. You can also search the forums for those commands and get a lot of information.

>>In addition, there're some procedures when
>>trying to add more space, you could do it
>>from the SAN, or from the server, but any of
>>those have different considerations.

This will depend on your environment.

A lot of arrays support increasing the size of a LUN. However, HP-UX itself does NOT support this, at least through version 11.23 (11iv2). In that case you have to add a new LUN, present it to your HP-UX server, and then extend the VG and the LV to use the additional disk space.

I **THINK** that HP-UX 11.31 supports LUN expansion but I am not sure. I haven't really worked with 11.31 yet. You should go to http://docs.hp.com and review the docs for 11.31 as appropriate.

By the way, the docs.hp.com site is almost always a good place to start when looking for HP-UX documentation.

[Torsten.]

11.23 and 11.31 supports

LVM Volume Group Dynamic LUN expansion (DLE) with vgmodify

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c01920387/c01920387.pdf (BSC link updated by admin)

[Marco A.]

Thanks guys, the information is great, and Torsten, this last one is great.

I do know that docs.hp.com is THE page for this kind of documentation but you guys have a lot of experience working in this kind of environments , so ...all the information that you have provided is very good, thank you.

Rgrds,

Marco

[Tim Nelson]

EMC specific ( might also apply to others ).

lvol creation should have bad block relocation turned off. The array takes care of this mapping.

lvchange - r n /dev/vgxxx/lvolx