topic Re: Create Disk Device Special File in Operating System - HP-UX

Create Disk Device Special File

Adam Garsha — Fri, 06 May 2005 10:02:09 GMT

I am going to be presenting some additional storage (virtual disk) to one of our HP-UX servers today.

The notes from the previous admin state that one can create the disk device files with:

insf -e

I am wondering if the "-e" is necessary and whether a preferrable method for a live system is instead:

insf -C disk

A second question is whether the "-e" option would have disrupted active processes on the system.

Goal: add disk, system live and active. How best to create device file?

Re: Create Disk Device Special File

Pete Randall — Fri, 06 May 2005 10:06:40 GMT

There are no ill-effects from running insf -e - no active processes will be affected. Usually the -e option is used simply because it's easier than figuring out the path to the particular disk - sheer laziness.

Pete

Re: Create Disk Device Special File

Uday_S_Ankolekar — Fri, 06 May 2005 10:10:41 GMT

You can run insf -e on live system without impacting anything.
If the kernel drivers are in place a fresh ioscan -fn should see your new disks after running insf -e

-USA..

Re: Create Disk Device Special File

Patrick Wallek — Fri, 06 May 2005 10:11:57 GMT

I usually just do an 'insf -e'. It may not be the best way, but it has always worked for me.

No, I have never had a problem with 'insf -e' disrupting anything and I have done it on live production system numerous times, including yesterday.

Re: Create Disk Device Special File

A. Clay Stephenson — Fri, 06 May 2005 10:12:10 GMT

Well, you could do an insf -C disk -e to restrict the device nodes to be added otherwise, insf -e will search for all device types. Either is considered to be a safe operation on a live system. No existing device nodes are removed.

My approach for connecting a new disk to a live system would be this:

add the disk (or LUN)
ioscan -fn
insf -e

You should now be able to pvcreate or use the raw device and assuming the hardware is "hot-plug" there is no need to shutdown.

Re: Create Disk Device Special File

Patrick Wallek — Fri, 06 May 2005 10:14:22 GMT

P.S. The procedure I usually go through is:

1) Define LUNs on array and set up appropriate WWNs in LUN access table (we use a VA7400 with Secure Manager)

2) Do an 'ioscan -fnC disk' to verify the machine can see the LUNs.

3) Do an 'insf -e' to create /dev/dsk and /dev/rdsk files.

4) Do an 'ioscan -fnC disk' again to verify /dev/dsk and /dev/rdsk files.

5) Do whatever LVM (create or extend VGs and LVs) work is necesssary.

Re: Create Disk Device Special File

Rick Garland — Fri, 06 May 2005 10:18:56 GMT

As everybody says, insf -e has had no ill effects. No changes to the device names or service interruptions. You could be more specific and just run insf with the specific options for that device.

Either way you will get you device files.