SUMMARY: Y2K test / disaster recovery

From: Gwynne, Alun P (
Date: Wed Aug 26 1998 - 04:13:18 CDT

My thanks to :-

Patricia Morgan (
Adrian Poparlan (
Tim Carlson (
Jay Lessert (
Wade Stuart (

(their responses below, followed by my original posting).
Who mostly homed in on the problem of license manager and the new
hostid. This can be circumvented by getting a temporary license or by
using software (hid2) to change the hostid (most popular). Jay included
a FAQ on hid from, so I've included the first few lines

However, no help available on recovering the entire system to a new
machine. Not even Sun had any specific papers on it, because disaster
recovery is normally done to the same hardware. I suppose not that many
machines actually go up in smoke. At the end of the day the consensus
seems to be that simply restoring chunks of root, etc, var, and other
areas is likely to cause more trouble than it's worth. Also, simply
recovering packages into /opt is not a very robust thing to do, because
you could miss dependencies like drivers and other files squirreled

So, I am recovering the whole of user data space, and /export/home , but
then configuring the system selectively to pick up installation-specific
stuff. Using sys-unconfig of course to make the system details correct.


Patricia Morgan (
If you are using veritas - vs another lvm - is it y2k compliant?

You are right about licenses - some are predicated on hostid. If you
more than one license say for sun compiler applications, you can borrow
or more for the test. Just call sun and tell them what you are doing.

Adrian Poparlan (

 In my opinion, best way is to hire exactly same type of
machine.(Attention at
prom versions on both machines if you are working for Y2K).
 I suppose that you can make the same filesystem structure using SDS and
restore a full dump of your tested machine.

You can very easy solve your problem with licenses using a sweet little
called hid2 (attached to this mail). It changes the HostID in memory
only, after
the system read it from NVRAM. So the content of the NVRAM remains
All that you have to do is a little script to start it at boot time just
the license manager.
Here you have an example:

/usr/local/bin/hid2 808newid

Name it S84hid2, put it in your /etc/rcX.d and check that starts before
Usualy lmgrd has S85.

There is another way to fake HostID, but working directly in NVRAM ( see
sunmanagers archives ). I think is not your case having hired machine.

                                        Good luck,
Tim Carlson (
> I also think that licence managers will not like our new hostid.

But you can change that on the fly in software. I think a pointer to the
software that does this is in the FAQ

Tim Carlson Voice: (505) 984-8800x255
Systems Manager: Santa Fe Institute Fax: (505) 982-0565
WWW: Email:

Jay Lessert (
On Fri, Aug 21, 1998 at 09:24:06AM +0100, Gwynne, Alun P wrote:
> I also think that licence managers will not like our new hostid.

Not a problem. Just spoof the hostid for your test, appropriate FAQ
included below.

Jay Lessert                    
Lattice Semiconductor Corp.                    (voice)1.503.681.0118
Hillsboro, OR, USA                               (fax)1.503.693.0540
From: (Mark Henderson)
Subject: FAQ: Frequently asked questions about Sun IDPROM/NVRAM/hostid
Date: 17 Aug 1998 06:12:10 GMT
Organization: -
Lines: 1392
.............................(FAQ included)

============================================================== Wade Stuart ( usage: ./hid2 <NEWHOSTID>

This is what we use to run tests like you are doing... It changes the HOSTID in the kernel and needs to be placed in a /etc/rc2.d script before the first hostid-bound proc runs. Please do not use this to avoid licensing your products.

-Wade ============================================================= My Original Posting....

> >Hi managers, > >We're about to embark on a Y2K test, which involves hiring a new machine >for a few weeks and rebuilding it with our live data/system. >In effect this is like a disaster recovery. The new machine will be >completely isolated on it's own little network of devices, so we can use >the same name, address etc. The disk subsystems are different, an A5000 >versus our SSAs, but we will live with this assumption. We want it to >look as much like the live machine as possible - names, addresses etc, >although the hostid will be different > >However, building it will include the system filesystems, but everything >that's not in /var and /export/home is in one large root filesystem, so >I'm concerned there are some gotchas that we haven't thought of. How >much of root can I really copy in ? For example, we will have to make >sure that we don't overwrite /dev , or the vfstab is not overwritten >when restoring. What about other /etc files? > >I also think that licence managers will not like our new hostid. > >Anyone have any experiences with this ? anyone have knowledge or >opinions ? > >Will summarise, and TIA > Alun > >

This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:12:46 CDT