Partitions
 

It is my understanding that a partition is a contiguous section of blocks on a hard disk. And that there are four primary partitions on an ide, and that 3 of these partitions are ?necessary? and the fourth is used as an extended partition which helps in managing logical partitions.


I am running Slackware 7.1
I have a /, /home, /usr, swap partition that i made. the last partition i made in setup was the /usr, which now has all the remaining hardrive space.

Looking at my /dev i see that there are all these logical partitions already there, ie. hda5, hda6, etc. Do these actually exist, or are they just there to tell me this is the convention used to for naming?

If i want to add another partition, I think I first need to change the size of my /usr partition. But in doing this it seems that I will loose all data on it. So I think I will need to copy the information to another partition, like /home, and then redo the /usr partition. Then copy back the data to the new partition. Is this generally correct?

Is there a way to mount something to, say, hda8, if I have not actually created it as a partition, and added a filesystem to it, without first going through a setup or fdisk?

Please help with any of the questions, or point out any incorrect understandings, or point me to somewhere.
thanks,
clu

I can only answer the first: it's the "standard" Microsoft created. Most commercial Windows tools are based on it. If you try to break it, the tools will warn you, but some would still let you. Windows wouldn't work or recognize the drives outside the area.

For Linux-only system, you can apply any standard you want as long as Linux recognizes it. On my distro, there are hda 1 - 32.

Your hda5+ do exist. hda4 is usually the logical part. It can't be mounted.

the hda* in /dev are place holders... logical devices without any real physical device to point to... think of /dev as a hallway full of doors... /dev/hda1 opens to /, hda2 to /home, and hda3 to swap and hda4 to /usr. Then hda5-n open to a wall... nothing there... no room to walk into. They're leftovers... they are only used if you have the partitions for them.

To add another partition... you're right. You'd have to copy the data over to another partition, delete partition, create partition,etc. if you can do a backup first though... while its not likely it is possible that by rewriting the partition table all data could be lost.

as far as mounting something to /dev/hda8... the files or nodes in /dev are devices... they get mounted ... things do not get mounted to devices. when you mount something, a floppy, a dvd drive, a usb hard drive, whatever... they typically get mounted to a directory in the /mnt hierarchy.

like /mnt/floppy, /mnt/dvd, or /mnt/usbdrive.

hope that helps,
barto