Re: Advanced Startup/Shutdown with Multilayered Block Devices and Related Issues
Goswin von Brederlow <email@example.com> wrote:
> There is one big problem with an event based startup. Specifically for
> raid1/4/5/6 devices. Those you can use just fine with missing devices
> but the boot should really wait for all device to be present.
Well, this problem arises with non-event-based startup as well. I don't
know how lvm deals with this but md keeps track of missing component
devices (mdadm -E /dev/component reveals "faulty removed" slots) and
defaults to refuse starting arrays when components are "unexpectedly
Debian's mdadm package, for example, insists on running such arrays in
the intiramfs code (i.e. takes precedence for a running system w.r.t.
required arrays) but doesn't do so in its normal init-script (i.e. takes
precedence for safe arrays if they are not required to boot the system).
Furthermore, mdadm ships Incremental Assembly for a while now.
Of course, this doesn't solve such issues automagically but makes it way
more easy to deal with them.
If you think technology can solve your problems you don't understand
technology and you don't understand your problems.
-- Bruce Schneier