mount FC10 disks from different machines

[Kirill Cherkashin]

Hi,

I have contecaned volume(6x18gb) connected through SAN network to two machines(L-3000,HP-UX 11.11). From time to time I need this volume to be mounted on one host or on another.
Important remark. I don't have cluster software and don't intend to use this volume in shared mode.
Could I use those disks on both machines without using vgimport/vgexport command? Just mount/umount on relevant box?

Kirill

[Paula J Frazer-Campbell]

Hi

Have you looked at NFS?

Export it from the host machine and nfs mount it on the second.

With nfs you can set many export and import params.


Paula

[Michael Steele_2]

Regarding "..I have contecaned volume(6x18gb) connected through SAN ... to be mounted on one host or on another...."

Can't do this without changing the device names and risking confusion ing your LVM configurations.

So just NFS it. This is what NFS is for.

vi /etc/exports
exportfs -av

(* No biggie :-). *)

[Kirill Cherkashin]

Of course I could. Not problem at all. But I use this volume for 65Gb database and how about its performance on NFS drive with 50+ network connections???
NFS was invented in 1985. I think that in 2003 year it's not a option.

[Eugeny Brychkov]

Kirill,
you can import VGs into many machines. Problems arise when you're trying to activate them. Please read output of 'man vgchange', especially '-a' section. When you have no MC/SG installed only avalilable options are 'y' and 'n'. When you have MC/SG installed, then there're two more options (at least two) 'e' and 'r'. Thus one system can have exclusive r/w access 'e' and another only read access 'r'.
It's risky to activate in normal r/w mode 'y' from both hosts. So yo accomplish what do you want you need MC/SG installed
Eugeny

[Paula J Frazer-Campbell]

Hi

It depends upon several items:-

1. Your network speed.
2. Your mount options.
3. What the users are doing.
4. The mount options.


NFS IS designed to do what you require.

To double mount a volume on two machine will cause problems in that which machine will have priority?

How will writes from each machine be controlled ?

NFS was designed to deal with the difficult tack of keeping the data viable when shared accross multiple servers.

It is tried an tested and I believe the solution to your problem.


Paula

[Michael Steele_2]

Krill, this is how you prefaced this question:

"...I don't have cluster software and don't intend to use this volume in shared mode..."

This is MC/SG.

This leaves you with NFS, autofs or Automounter and the latter rely upon NFS first being configured.

If you're worried about network bandwidth problems then this is what autofs and automount are all about. Hundreds of users and I've heard of 2500 users before, all using the same exported file system from one server.

Heard of Clearcase before. New popular product that a lot of people are buying up and implementing. Its all NFS and automount. But because its sold under the Clearcase name they rename it and tweak it a little.

Heard of TCP wrappers? Real popular IP filtering product everyone's buying up. Its virtually identical to inetd.sec which has been around for decades but has lost its marketing appeal. And people use TCPwrappers when they've already got the inetd.sec utility built into their CORE O/S.

Don't fall into the "keeping up with the 'Jones's'..." quagmire.

Use NFS.