Why New Install of 11i rather than an Update from 11.0 to 11i?

[Laurie A. Krumrey]

Hi All,

I was in a meeting with my DBA's and I was
trying to explain to them why I would rather
do a clean installation of 11i rather than
an upgrade from 11.0 to 11i.

The problem is that one of my DBA's thinks he
is a Unix person (why does everyone who knows
vi think they know Unix).

I was trying to explain (not very well) that
I needed to increase the root and stand
directories size and that I could not do the
upgrade with the current file size.
That I need more room in STAND and root
and that the disk space has to be continous.

He then wanted to know why I just couldn't
increase the directory in single user mode
and why I need more space in the stand directory, when I could just copy backup
vmunix.prev to another directory...

Please Please help me. I need to be able to
explain to the DBA's and my new boss my
reasons for wanting to do a new install of
11i rather than updating our current 11.0
to lli.

I need to be able to explain this in real
easy English, yet technical enought to
keep my DBA/unix-want-to-be person from
debating me.

Thank you for your time and help,
Laurie

[harry d brown jr]

Laurie,

Tell your DBA that you CAN NOT increase /stand from single user mode because it NEEDS to be CONTIGOUS.

Tell your DBA (your /dev/null unix guru) to do this in vi: :1dG:wq!

A clean install, versus an upgrade, insures you you have no lingering things from the prior release. A clean install takes about two hours, and then maybe another one or two to restore and customize your system. An upgrade, if it fails (which they do a lot) will automatically cost you a few hours. Then the second attempt a few more hours. then the third attempt.....

And most importantly, a clean install removes a lot of garbage that might have been installed in the prior release that you don't care to take forward into the new relese.

live free or die
harry

[Jeff Machols]

Laurie,

If you do a pvdisplay -v on the disk that contains your root filesystem, it will show you what LE's are allocated to what Volume Groups in order. If are any LE allocated anything after the root logical volume, that proves you can extend a continous LV.

[Jeff Machols]

oops, I had a typo in my last line, should be

proves you can NOT extend the LV.

[Christopher Caldwell]

I'd ask your quasi database admin Unix guru why he cares.

If the system has a decent layout (i.e. neither the database nor the database software are on vg00), there "should be" (tm) little difference from his perspective between an upgrade and a clean install.

You'd export the file systems with the database junk, build the new system, then import the exported file systems. Thus the database jockey shouldn't really care what happened in the interim.

If you promise not to help with database tuning, perhaps he'll promise not to help with Unix intalls ;-).

[Ian Dennison_1]

One of the best arguments I have used in situations like this, is that the 'HP Technical wizards I talk to every day' have recommended install of 11i for security and reliability of the process.

A 'work-around' may prove quick in the short term, but Install Engines are better equipped to know where everything goes (and in what order). I have had installs that have been 'tweaked' by others to get them to work, only to have me work for 4 weeks to get the full functionality of the system back.

Quicker is not necessarily better!

As an aside, most times I have started in a new UNIX role, someone (DBAs, Users, Programmers, or even Managers) has tried to see how far they can push into the Sysadm territory. Stand your ground or forever be on the back foot!

Share and Enjoy! Ian

[Wim Rombauts · Accepted solution]

Giving it a try to explain in plain english what the trouble is if you need more space in /stand and root.

Physically on the harddisk, the stand and root filesystems and the swap area are glued together, one against the other. There is no free space between them. Your UNIX guru probably knows that /stand allways has to be the first in the row. Now tell him the root disk is the second and swap the third.
Since /stand, root AND swap need one contiguous space, let him explain how to expand the /stand filesystem without overwriting the beginning of the root filesystem on the disk. Let him explain to you how you can "move" your root filesystem physically on the disk.

Oh yeah , there is a procedure to increase /stand and root without a fresh install. It requires the recovery media and a set of low-level backups able to restore /stand and root - so in fact you are removing the OS from your system.

I have "upgraded" our server twice, but allways did this with a fresh install. This is the only SURE way that your OS configuration is OK and that no special configuration from the current version has confused the upgrade tools and leaves you with a system that gives you more trouble than it's worth.

[John Payne_2]

Laurie,

If you have a 32-bit install of 11.0, it is easy. They may not see the need for a 64-bit OS now, but what happens in a year or so when they do?

Tell them freash means fresh! You do not have to worry about ANYTHING from 11.0 accidentally migrating into the new OS and fouling things up. We ALWAYS do a fresh install. (Besides which, I always like to ask someone why they do not want a fresh install, then start hinting that if they so desparately want the old stuff in there still, they must have found a way to hack something they want to keep, so I ask what it is they want to keep.)

Tell the DBA that the vmunix.prev he says to move is part of your contingency plan for an unbootable system. It always has been, and it always will be, as long as kernels continue to be regened. Moving the file elseware is not good engineering, and you need the space!

If / is not big enough for you, you need the space. Better to reinstall and expand it while you are at it than have an non-functional system in a few months time because / filled up.

I agree with Ian, do not give him an inch more than you think you should.

[Timothy Czarnik]

Laurie,

In the simplest terms, a fresh install and an upgrade may take the same amount oftime to do, but all the troubleshooting that g oes hand in hand on an upgraded system will far outweigh the restore time to a fresh system.
Let them cry and whine, but in the end, you're the one who has to administer this system. Stick to your guns. Tell the DBA to ram it (in the nicest, most sensitive way possible, of course)!

-Tim