On Qua, 26 Jan 2011, Brad Alexander wrote:
Because if your laptop gets stolen, the odds are that they will not get the USB drive. Thus, it is another layer of security. Plus, if they have /boot, they will be prompted for the passphrase, which means they can brute force it.
Only if the user is using a dumb passphrase like "password" or "123456". Or if the attacker can wait years (or decades) for the data.
Moreover, if the user wants the data (which is not so common, but could happen), not having a /boot does not prevent brute force attacks. One just needs to remove the hard drive and try to mount in another system, and they'll get the same passphrase prompt.
-- Tempt me with a spoon! Eduardo M KALINOWSKI eduardo@kalinowski.com.br