HPUX DEVID ENHANCEMENT

[Todd Whitcher]

What is It?

HP-UX now supports the storage and retrieval of Device ID's in /etc/mnttab. This is for use by every type of filesystem, including AutoFS.

The Enhancement is only Available for HPUX 11.X

The biggest advantage this gives us from the AutoFS perspective is that we no longer have to walk the mount table and stat() every filesystem BEFORE unmounting. When we do this, we have seen that we can hang for a few seconds when we are stat'ing a file system on a down server.

Why Would you Want it?

The primary reason that customers want this behavior is to avoid the over-the-wire stat() calls from HP-UX AutoFS clients to servers to match a Device ID before performing an unmount.

If a server is down, then other NFS and AutoFS processes can be delayed while we are waiting for the stat() call to timeout. This can cause very serious delays in some environments.

With this functionality, automountd (and other processes) can simply "look" in /etc/mnttab for a matching device ID and send the umount request directly to the correct server

Who Can Have it?
Any customer who wants this functionality can have it.

How To Get it ?
It is available publicly at software.hp.com

Go to http://software.hp.com

Select enhancement releases
Select deviceids Follow the instructions to get the correct version Follow the installation instructions to install and verify operation

Regards,

Todd Whitcher