proper cacti installation

I was trying to set up cacti for my ubuntu 10.10 server.

Problem is that there is开发者_如何学Go no images in cacti when accessed.

Uploaded, set up database but there is error if I launch pull.php from ssh:

ERROR: creating '/mnt/laptopshop/cacti/rra/localhost_users_6.rrd': Invalid argument
ERROR: mmaping file '/mnt/laptopshop/cacti/rra/localhost_users_6.rrd': Invalid argument
ERROR: creating '/mnt/laptopshop/cacti/rra/localhost_load_1min_5.rrd': Invalid argument
ERROR: mmaping file '/mnt/laptopshop/cacti/rra/localhost_load_1min_5.rrd': Invalid argument
ERROR: creating '/mnt/laptopshop/cacti/rra/localhost_mem_swap_4.rrd': Invalid argument
ERROR: mmaping file '/mnt/laptopshop/cacti/rra/localhost_mem_swap_4.rrd': Invalid argument
ERROR: creating '/mnt/laptopshop/cacti/rra/localhost_mem_buffers_3.rrd': Invalid argument
ERROR: mmaping file '/mnt/laptopshop/cacti/rra/localhost_mem_buffers_3.rrd': Invalid argument
ERROR: creating '/mnt/laptopshop/cacti/rra/localhost_proc_7.rrd': Invalid argument
07/16/2011 06:29:07 PM - SYSTEM STATS: Time:1.2707 Method:cmd.php Processes:1 Threads:N/A Hosts:2 HostsPerProcess:2 DataSources:5 RRDsProcessed:5
ERROR: mmaping file '/mnt/laptopshop/cacti/rra/localhost_proc_7.rrd': Invalid argument

I was trying to google for it but nothing good. So any ideas?