I have deployed a CentOS with CACTI to function as network traffic monitoring a few  weeks ago. In  fact , it is a CACTI livecd  named CactiEZ ,that just need boot from CD/DVD and after installation all functions are ready. So, U can call it all in one CD, isn't it?   Additional , the cacti server is deployed in a virtual server that base on Microsoft virtual server2005.
    It is cool application , i can get the traffic report  with some figure to figure out whether the host/router has bottle-neck in traffic. At the meantime, i found a problem , the system time of  cacti virtual server ran very very faster than my desktop. So when you  check a device's current traffic figure , it will present "tomorrow'  time sheet, because the server's system run very faster, when you on 20th june , the vm server on 21th june.
     so strange !! Finally i worked around the problem according below details:
       1. edit /etc/grub.conf   (added RED content)
 kernel /vmlinuz-2.6.9-89.0.25.plus.c4smp ro root=LABEL=/ divider=10 clocksource=acpi_pm
       2. edit /etc/sysconfig/clock
     ZONE="Asia/Shanghai"
     UTC=false
     ARC=false
     3. make a schedule for ntpdate
   crontab -e
*/1 * * * * ntpdate 192.168.1.1                                 192.168.1.1 is my ntp server in my LAN.
   4. clock -w

     Ok, when i thought the problem has solved , a bigger trouble was waiting for me when i reboot the virtual server.
System crashed , a message was presented     Kernel panic: Attempted to kill init!  
      Fallback all operation i have done previously  in my mind. I found the cause , it is a file locates /etc/grub.conf, because , i just edited it  and missed a space between "/" and "divider" ( the red font content in previous content ), the boot parameter can't invoked . So, i have to boot the system with grub command.
   Enter grub command mode. In my environment,i According below sequence  to boot system
   1. root (hd0,0)
    2. kernel /vmlinuz-2.6.9-89.0.25.plus.c4smp ro root=LABEL=/ divider=10 clocksource=acpi_pm
    3. initrd /initrd-2.6.9-89.0.25.plus.c4smp.img
    4. boot
Yes, above content just is the grub.conf‘s。All  these just type the file’s content to load the system manually。 Then i correct the incorporated content。
 The grub command a reference link    ---  http://www.mepis.org/docs/en/index.php/GRUB_from_command_line