I am using the Fedora Core release 2, but i find the light of my harddisk would be lighted every 5 seconds.
it seems that something access the harddisk periodically .
My hardisk runs well under the OS windows .

how to fix it ?

Thanks very much

Does the light turning on adversly affect performance? If not it might be a part of the normal Fedora function. I find that windows in fedora (nautilus windows) update themselves much faster and often without having to reload. It may very well be a part of Fedora's standard run procedure.

That would be the journal getting updated on your file system(s) if you choose either ext3, reiserfs ... to stop it I believe you should add the noatime option to the line(s) for the file system(s) being used in the /etc/fstab.

Interesting solution. What are the implications of stopping 'the journal getting updated'?.

I try it with your method, but it can't resolve that problem.

I think I'm out of ideas then that is what stopped it on mine, perhaps it is only with reiserfs ...

ohh,it's my wrong ----i forgot to reboot the PC when i had modified /ect/fstab
Your method is correct, it is the same with ext3 file system .

Problem was solved !

Thanks very much !

HappyTux, here's my fstab. I tried to insert noatime into / and /boot, and Fedora would not boot. How would I change it?

LABEL=/ / ext3 defaults 1 1
LABEL=/boot /boot ext3 defaults 1 2
none /dev/pts devpts gid=5,mode=620 0 0
none /dev/shm tmpfs defaults 0 0
/dev/sda1 /mnt/winxp_c vfat defaults 0 0
/dev/sdb5 /mnt/winxp_d vfat defaults 0 0
none /proc proc defaults 0 0
none /sys sysfs defaults 0 0
/dev/hdd3 swap swap defaults 0 0
/dev/cdrom1 /mnt/cdrom1 udf,iso9660 noauto,owner,kudzu,ro 0 0
/dev/cdrom /mnt/cdrom udf,iso9660 noauto,owner,kudzu,ro 0 0
/dev/fd0 /mnt/floppy auto noauto,owner,kudzu 0 0

The hard disk light flashing every 5 seconds is most likely the way the write behind cache works under linux.
If you run 'free' you'll see that a big chunk of your ram is being used as disk cache. (K System Guard illustrates this nicely). If you have a facility for watching the drive access (i sometimes use the disk perfomance plugin for the xfce taskbar) you'll see that instead of almost constanly writing to your hard drive like windows, linux does it a big chunk at a time.

Translated into english: "It's quite normal".

Also note the noatime does not disable journalling. It just disables the recording of the last time you accessed a file. This is VERY essential if you're running an os from read only media, or media that it's best not to write to frequently. It' will increase performance, but can caue problems, for example if you have a script that backs up files you've changed in the last week, it won't be happy.