How new disk can be visible on OS

smilemukul · 11-16-2010, 02:05 PM

I am working in a production env & working with SAN team to extend the new hard disk in the production env.
I wanted to extend the disk through LVM as the existing disk is fully utilized.The disk is added in the production env by the SAN team but how can I see that the disk is added so that I can extend the disk using LVM.

Is there any command so that I can see that the disk has been addeed in the OS(redhat).

Thanks

kbp · 11-16-2010, 04:41 PM

Try these commands, bit hard to tell what your layout looks like now and what you want it to look like -

1. pvresize
2. lvextend
3. resize2fs

or

1. pvcreate
2. vgextend
3. lvextend
4. resize2fs

Sorry, just re-read your question, are you adding a new disk or extending an existing disk ?

hth

chrism01 · 11-16-2010, 08:03 PM

fdisk -l

as root shows what disks are visible to the OS, then you can use the above cmds to attach it.
See also http://tldp.org/HOWTO/LVM-HOWTO/

smilemukul · 11-17-2010, 12:22 PM

Let me make the question more clear that, its a new hard disk which SAN team need to add & which will be reflected in the kernel or OS.

I want to see the new disk added in the OS by the SAN team before creating a phyical volume or extending a disk.

Thanks

kbp · 11-17-2010, 04:07 PM

Determine which controller the new disk is attached to then -

Code:

echo "---" > /sys/class/scsi_host/host<X>/scan

This will cause the controller to rescan and detect new disks

hth

smilemukul · 11-18-2010, 12:08 AM

Thanks but I am getting a Permission Denied message while login through root.

Thanks

smilemukul · 11-23-2010, 11:38 AM

I am getting a permission denied message while accessing the command,

echo "---" > /sys/class/scsi_host/host<X>/scan

Also how can i check the controllers information through a cammand ?

Any response will be appreciated

Thanks

TobiSGD · 11-23-2010, 12:13 PM

Sorry, I can't help with your questions, but it seems to me that you don't know much about this things. So may I ask, and no offense is meant, if you really think that doings things that you not really understand in a production environment is a good idea?

smilemukul · 11-23-2010, 12:21 PM

I am testing the above command on the testing machine first

Please let me know if you have any solution ?

Thanks

smilemukul · 11-29-2010, 12:43 PM

Can anyone help me regarding my question ?

Thanks