Ubuntu :: Increase Maximum Amount Of Allowed Shared Memory?

My problem is I installed Zone Minder for camera security and I'm testing it on my laptop with the built in webcam and everything seems to work perfectly except when I try to view the live feed from the camera, it's just a black box. No video.

I checked this website and it's exactly the problem I'm having with a fix for it but his fix doesn't work. He says to type:

Code:
user@ubuntu:~$ sudo echo "256000000" > /proc/sys/kernel/shmmax
user@ubuntu:~$ sudo service apache2 restart
user@ubuntu:~$ sudo service zoneminder restart

But when I do the first line, I get this:

Code:
deemar@Clementine:~$ sudo echo "256000000" > /proc/sys/kernel/shmmax
bash: /proc/sys/kernel/shmmax: Permission denied