zfs boot vs loader

[Anonymous]

Andriy Gapon <avg at icyb.net.ua> writes:

> I am using ZFS for boot-and-root filesystem. gptzfsboot is used for bootstrapping,
> if that matters.
> Maybe the following is some kind of a pilot error, but I think that I see a
> problem with selecting a different kernel using loader prompt.
> That is, I escape to a loader prompt from boot menu. There I do 'unload'. Then I
> 'load' a different kernel, opensolaris.ko and zfs.ko. Then I 'boot'. Then root
> mounting inevitably fails because ZFS root filesystem can not be found.
>

You can just type

    OK boot kernel.old

here to switch to kernel.old (or any other one). No need to manually
load modules if you specified them in loader.conf.

> This is an unexpected result for me.
> I wonder if something important for ZFS get unloaded when I unload preloaded
> kernel and modules. Perhaps I have to manually re-load zpool.cache?

Does following help?

    OK load -t blah /boot/zfs/zpool.cache

>
> This happens with recent CURRENT, amd64.
> What's strange is that I think that I can switch kernels from loader prompt
> without any problems when using RELENG_7 and UFS-boot-plus-ZFS-root approach.