Hi,
In message ,

I wrote

| Basically I keep a single fdisk partition containing the entire disk,

| but two sets of OpenBSD root, usr, and now var partitions inside that,

| both sharing /home and /data (where I keep my user files):

|   wd0a       root        fstab mounts root, usr, var, home, data

|   wd0b       swap

|   wd0c       entire disk

|   wd0d       root2       fstab mounts root2, usr2, var2, home, data

|   wd0e       var

|   wd0f       var2

|   wd0g       usr

|   wd0h       usr2

|   wd0j       home

|   wd0k       data

|

| I use the standard OpenBSD bootloader; typing "boot wd0a:/bsd"

| (or just doing nothing and waiting for the 5 second default timeout)

| boots the wd0[aeg] set of partitions, while "boot wd0d:/bsd" boots

| the wd0[dfh] partitions.
On Sun, 25 May 2008, Leo Baltus wrote:

quoted text
> This is still pretty obtrusive, i.e. making a backup, then

In practice, the backup takes an hour or two once every 6 months

(when the new OpenBSD comes out), which I don't find too much of a

burden.

> overwrite filesystems you normally use,
The backup (copy a,e,g to d,f,h) doesn't overwrite filesystems I

"normally use"; it overwrites a *backup* set of filesystems which

I typically haven't even mounted for some months.  That is, my wd0a

/etc/fstab mounts *only* the a,e,g,j,k partitions, so when booting

from wd0a, the d,f,h partitions are not mounted.  Similarly, my wd0d

/etc/fstab doesn't mount the a,e,g partitions.  (The idea is that

having the "other" set of partitions unmounted keeps them safe from

a great many rm-in-the-wrong-directory type sysadmin blunders.)
> hoping the backup is a copy

quoted text
> you can rely on.

This is a very important point.  I completely agree, backups are

useless if I can't rely on them.  So I test them as best I can

before proceeding with an upgrade/reinstall on the a,e,g partitions.

For example, for my 4.2-stable --> 4.3-release transition, my sequence

was:

1. copy 4.2-stable a,e,g --> d,f,h, run installboot on d

2. reboot from d,f,h and use laptop normally for 4 or 5 days to make

   sure that the d,f,h 4.2-stable works normally

3. fresh install of 4.3-release on a,e,g

4. reboot from a,e,g 4.3-release, work through my usual post-install

   checklist of config file edits, packages, one or two ports, etc etc

5. use laptop normally running a,e,g 4.3-release; track down & fix any

   remaining glitches that come up (I might hand-mount d,f,h read-only

   for a while, just to have them handy for glitch-fixing)
After step 2 I don't have to just "hope" the d,f,h backup is a copy I

can rely on.  Rather, at that point I've been using the d,f,h partitions

for all my day-to-day work for 4 or 5 days, so I'm pretty confident that

they're ok.  (If they didn't work ok, then I'd want to fix the problems

before proceeding.)  Of course that "testing time" can be adjusted to

taste; it's probably more usefully measured in what-tasks-I've-done

rather than wall-clock-days.
> This would all be unnecessary if the bootloader could be informed that

quoted text
> it should boot from wd0d:/bsd from now on, so you could leave wd0a: et.

> all unharmed. Is there really no way to do that, other than by typing it

> on the boot prompt?

>

> Alternatively, is there a way to safely switch labels in the

> labeleditor, so that wd0a would become wd0d and vice versa?

--

-- "Jonathan Thornburg [remove -animal to reply]"

   School of Mathematics, U of Southampton, England

   "Space travel is utter bilge" -- common misquote of UK Astronomer Royal

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   "All this writing about space travel is utter bilge.  To go to the

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