At 11:22 AM 1/31/97 EST, you wrote:
>All right, I'm showing my ignorance (again).  We're looking at
>connecting two HP3K's located in different states.  I getting quotes
>on T1 or frame relay connections between sites.  We want to use the
>remote computer as a hot site for data recovery.  That means we'll
>be using SharePlex/NetBase to shadow the data from the "home"
>computer to the "remote" computer.
>
>1)  We won't be using the remote computer for any processing (except
>for the data shadowing), so I don't think we'll need the full SharePlex
>/NetBase Bundle (Product #A2359A/A2360A).  I think we only need the
>Shadowing product (#B3933AA/B3934AA).  Correct?
>

I'm not sure.


>2)  Disk Mirroring is sometimes mentioned as being hand-in-hand with
>SharePlex/NetBase, but appears to protect against disk failures by
>automatically switching to the mirror disk if the primary disk fails.
>So, if I can make provision to recover from a disk failure (incurring
>some downtime) by switching over to the backup system, I don't really
>need Disk Mirroring (unless I want zero downtime).  Correct?
>

Yes but many shadowed sites also use disk mirroring especially now that
we no longer have sector-atomicity in the disk drives we use.  Also,
disk mirroring makes a lot of sense in large disk configurations.  I
have a customer who has 100 4 gb drives in a single volume set.  They
better darn sure mirror because of the time it takes to reload all that
data and resynchronize the Netbase stuff after recovery.

>3)  If #2 is correct, I can get around a bad disk by switching everyone
>to the backup computer system (by using OpenView System Manager and DTC
>Manager).  Correct?
>

Correct.  I was speaking with a customer today who removed disk mirroring,
kept shadowing and within three days had a disk failure.  The cutover took
five minutes.  The recovery is another story.

>4)  OpenView requires the Management Node (home system) to have MPE/iX
>4.5 or later and ThinLAN 3000/iX Link (36923A) which is bundled with
>5.0 (and later?).  The Managed Node (remote system) must have MPE/iX 2.1
>or later, and DTC X.25/iX Network Link or X.25 Link, and NS3000/Ix (36920A);
>OR ThinLAN 3000/IX Link (36923A) - which implies MPE/iX 5.0 or later; OR
>NS Point-to-Point Link (36922A).  My question is "If I have two systems on
>MPE/iX 5.5, do I need anything else to make OpenView work?".
>

I'm not sure.

>5)  Disk Mirroring only works with disks attached to the same computer,
>SharePlex/NetBase works with multiple computers.  Correct?
>

Correct and correct.  Also, you can only mirror user volumes so if you are
planning a "highly available system" you will also need to consider changing
your system volume set to disk arrays and moving all production to user
volumes (if you haven't already, and if you haven't, why not :-) )


>Thanks for any answers you can provide, or any other comments and help.
>

You're welcome!


>Jim Phillips                            Manager of Information Systems
>E-Mail: [log in to unmask]      Therm-O-Link, Inc.
>Phone: (330) 527-2124                   P. O. Box 285
>  Fax: (330) 527-2123                   Garrettsville, Ohio  44231
>
>


Bill Lancaster