The usb/cf is mounted as readonly so when configuring the apk cache you need to manually remount rw, create the cache dir and then again maually remount rw.

We can either create a simple tool for this, (that maybe also configures LBU_MEDIA?) or we could simply create an empty dir on iso image named ‘cache’ that are automatically copied over to usb whith setup-bootable.

(from redmine: issue id 661, created on 2011-05-26, closed on 2011-10-27)