Step By step Configuration of Logical Volume (LVM)

[Fateh Malik]

I am new in LVM, & I want to have confidence on LVM, for This reason May I have Step by Step procedure for creating Logical Volume from Physical Volume/volume group/Logical volume.
For Example we have we have two disk c0t0d0 & c1t0d0.

How I will proceed.
Thanking you all in advance.

[Torsten. · Accepted solution]

See if my response in this thread helps you too:

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1143382

[Court Campbell]

This is a good starting point:

http://docs.hp.com/en/B2355-90950/ch06s01.html#bficdcif

There is a section called "Creating a Logical Volume Using HP-UX Commands" that will show you the basic steps.

[Torsten.]

BTW, make sure non of the disks is already in use by another vg!

Check your current configuration first, run
strings /etc/lvmtab
vgdisplay -v
to do this.

[Avinash Agarkar]

Hi Malik,

Simple proceduce is -

ioscan -fn
insf
ioscan -fnCdisk | more
check weather new disk is detected.
pvcreate -f /dev/rdsk/c0t0d0
mkdir /dev/new vg name
cd /dev/new vg name

check the group file with
ll /dev/*/group

make a node file with
mknod group c 64 [major and minor no]

create a vg with
vgcreate /dev/new vgname

check vgdisplay -v new vgname
create the new lv
lvcreate -L size -n lvname /dev/new vg name

mkdir new mount point name

newfs -F vxfs -o largefiles /dev/new vgname/rlvname

mount it

then if you want to mirror this

lvextend -m 0 /dev/new vgname /disk path

or if u want to extend the vg then

vgextend /dev/new vgname /disk path

Thanks,
Avinash

[Fateh Malik]

Hi All,

Kindly find the attached output of ioscan & strings /etc/lvmtab run on my two rp4440 systems, these systems are connected to EMC SAN storedge and all disk are accessbile.

Kindly give me the green signal that I practice Logical volume creation on these systems, with help provided by your replies

Also practicing this how I will put them back to current situation.

Thanking you in advance!

[Doug O'Leary]

Hey;

I haven't had to refer to it in a very long time as I've done LVM commands so much I can do them in my sleep, but I have a checklist for LV creation:

http://www.olearycomputers.com/ll/hplvcreate.html

It has links for for pages on creating volume groups and filesystems as well.

The attached script, id_lv_disks, will show you which disks on the system are available, parts of volume groups, or are alternate links to disks that are part of volume groups. Any disks listed as unassigned *should* be usable for your learning/testing.

This version works for systemss with only one dvd/cdrom. I have another later version (just not handy) that works for systems with more than one. Lete me know if you need it.

HTH;

Doug

[Torsten.]

I guess nobody can give you an approved green light here.
You have just to ensure the "disks" are not in use by somebody else. Ask your SAN admins, for example. Even raw devices could be in use. Also a wrong zoning could lead to data loss if you perform a pvcreate on wrong disks.

This is a user to user forum and we all try to help each other, but we don't do the others job ;-)

If you need, you can find this link on many ITRC pages, refering to consulting:


http://h20219.www2.hp.com/services/cache/109655-0-0-225-121.html