Remounting does not work if a normal user is logged in because /home is busy (in use). You might need to switch to runlevel 1 (init 1), which is single-user mode, to remount /home.
Now you can run fsck on the partition. When done,
# mount -o rw,remount /home
puts it back in service.
If you reboot your system to mount the root file system read-only for maintenance (enter the maintenance mode, s, as described in Chapter 11),
# mount -o rw,remount /
will remount it read-write and you can continue on. That's easier than unmounting and remounting the device.
Examine an initrd Image File
The initrd.img file is automatically created during the installation process (if necessary) or with the mkinitrd command. You never need to examine it, but if you are curious about what's in the initrd.img file, just take a look: It is really just a gzipped ext2 file system. To examine it, first copy it to the /tmp directory and add the .gz suffix to it:
# cp /boot/initrd-2.6.7-1.478.img /tmp/initrd-2.6.7-1.478.img.gz
If your system does not have an initrd.img file in /boot, mount your boot floppy and see whether it has one. Next, uncompress it as follows:
# gunzip /tmp/initrd-2.6.7-1.478.img.gz
Mount it as follows:
# mount -o loop /tmp/initrd-2.6.7-1.478.img /mnt/image
and browse the directory to your heart's content.
Not every system has an initrd.img file. It is typically used to load device drivers for file systems (such as Reiser) or hardware (such as the Promise RAID IDE controller) that must be in place before the system can continue booting. Some floppy-disc-based Linux distributions use initrd.img to load a minimal operating system that can then uncompress and load the working file system from the floppy.
You can also mount .iso images in the same way, but remember that they are always read-only because of the nature of the underlying iso9660 file system; you can write to the other images unless you explicitly mount them as read-only. If you want to read and write to the files in an ISO file system, you must first copy the files to a device that is mounted read-write, make your changes, and then use mkisofs to create a new .iso image. This is a common 'gotcha' for many users.
You use these commands when managing file systems in Fedora:
> df — Shows free disk space
> du — Displays disk usage
> dump — An ext2 file system backup utility
> dumpe2fs — Shows information about an ext2 file system
> e2fsadm — Administers an LVM/ext2 file system
> e2image — Creates an image file of ext2 file system data
> fdisk — The standard Linux partition table editor
> fsck — Checks or repairs a file system
> lsraid — Displays information about Linux RAID devices
> mformat — Formats a DOS floppy disk; part of the Mtools suite of tools
> mkfs — Creates various file systems and acts as a wrapper for the actual programs that do the work
> mkisofs — Creates a CD-ROM file system in iso960 format
> mkreiserfs — Creates a Linux reiserfs file system
> mkswap — Prepares a Linux swap device
> mount — Mounts a supported file system
> parted — The GNU partition editor and resizing utility
> reiserfsck — Checks a Linux reiserfs file system
> resize_reiserfs — Resizes a Linux reiserfs file system
> smbmount — Mounts an smbfs file system
> stat — Shows file or file system status
> swapon — Displays swap usage or start using system swap device
> swapoff — Turns off swap usage
> sync — Flushes file system buffers
> tune2fs — Changes file system parameters on ext2 file systems
> umount — Unmounts a file systems
> usermount — The Fedora graphical file system mounting and formatting tool
Reference
> http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html_single/Ext2fs- Undeletion.html — You deleted a file on your ext2/3 partition? The Linux Ext2fs Undeletion mini HOWTO is there to help you out.
> http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html_single/LVM- HOWTO.html — Throw away those concepts that marry physical disks to finite-sized file systems; the Logical Volume Manager HOWTO explains how to overcome that kind of restrictive thinking.
> http://www.math.ualberta.ca/imaging/snfs/ — Secure NFS via an SSH Tunnel is a very interesting attempt to address a security shortcomings of NFS over a public network.
> http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html_single/NFS- Root.html — The NFS-Root mini HOWTO.
> http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html_single/NFS-Root-Client- mini-HOWTO.html — Explains in detail how to set up and use NFS for exporting root file systems.
> http://www.ibiblio.org/pub/Linux/docs/HOWTO/other-formats/html_single/Tips-
