initramfs init should apk add --best-effort
If you upgrade alpine and a package that used to be on the cdrom is no longer there, it will break and launch an emergency shell.
We could probably add —force to apk add, but then it will continue even if it gets signing key errors etc.
Other option could be to test if each requested package is available before apk add is called and warn about those who are not.
(from redmine: issue id 297, created on 2010-02-26, closed on 2010-02-26)