If you want to hide linux boot time messages or store them to a specific location then you could edit the /etc/inittab file and change it as follows:
rc::bootwait:/sbin/rc boot > /dev/null
l0:0:wait:/sbin/rc shutdown > /dev/null
l1:S1:wait:/sbin/rc single > /dev/null
l2:2:wait:/sbin/rc nonetwork > /dev/null
l3:3:wait:/sbin/rc default > /var/log/rl3
…..
Note that this example is taken from Gentoo Linux.