Making the Switch-04: The "User Guide" as life raft, more n00b problems

[zridling]

After you've installed your distro, take the time to walk through the various user guides offered online. They will provide an installation guide, a complete tour of the desktop, along with how to manage software installation and upgrades to help get started. I had to go back to square one when I realized that there were too many subtle differences I wasn't understanding. A user guide helped me understand that ALT+Tab can manage separate desktops (if you setup more than one), for instance, rather than merely switching among open apps.

Some things in GNU/Linux are surprisingly simple. No, really. Take DVD burning. This is all there is:

• Open a Nautilus window, such as Home or Computer. (Nautilus is the file manager.)
• Select Places > CD/DVD Creator.
• Drag and drop the files you wish to burn into this new empty window.
• Click Write to Disc.
• In the dialog box, you can change the name of the disc and the write speed if they are incorrect.
• Click Write.

And holy crap, it works. Same for my USB flash drive. Even though it was "Vista certified," it would only work in Vista if you applied a low-level format utility in XP! And then Vista wanted to reformat it every single time you inserted it. Under Fedora 7, it was recognized, and "mounted" on the desktop for me to open, copy, delete files to and from. Again, I'm surprised by that because of all things, I figured DVD burning and USB drives would be difficult. Similarly, playing audio files are not difficult either. Here's what the Fedora 7 user guide had to say:

                 Fedora includes complete support for many freely-distributable formats. These are the Ogg media format, Vorbis audio, Theora video, Speex
                 audio, and FLAC audio formats. These freely-distributable formats are not encumbered by patent or license restrictions. They provide powerful
                 and flexible alternatives to more popular, restricted formats such as MP3.

Ogg is a nice, high-quality format, but I'm not converting 40Gb of MP3 files, especially since the MP3 patent expires in 2011. Not a problem. That's fixed by merely downloading the LAME encoder. GNU/Linux supports every audio format except for WMA, which is only partially supported.

[attach]

[Tonurics]

Hard drives in linux are quite a bit different that what we are used to from windows. One of the big things that most people don't pick up on (especially when dealing with two hard drives) is that you are not locked into only mounting your hard drive at a fixed location (in windows, your stuck using a drive letter) you can mount your drive anywhere you want; for example you could mount your second drive at /home (think of /home like the windows profile folders, inside you have your desktop folder, my documents, my music, etc) which would make your system save all your personal data on the second drive, leaving your root drive (first hard drive, which has the os installed on it) untouched. This all happens transparently so if you removed your second hard drive and put it in another linux computer (and mounted /home there) all your files would travel with you, your original would also continue to work as /home would default back to the root drive.

Anyways, hopefully that is enough back-story to give you a better understanding on linux hard drives. Now for mounting your disk.

Firstly using /dev/[device] seems to be slowly going the way of the dodo (not that it wont work) but there is a good chance a kernel update to your system later on will break your mount points. Also the /dev/[device] links are pretty organic, you may plug in a new hard drive later and find all your device numbers has shifted (/dev/sda could become /dev/sdb etc.). But there is a simple fix:

In a shell run: ls -l /dev/disk/by-uuid/

You should see something like:
lrwxrwxrwx 1 root root 10 2007-06-14 08:23 34hj34h-34jhg-434h-8345-k3h434k5hkjh -> ../../sda1
lrwxrwxrwx 1 root root 10 2007-06-14 08:23 s7d7sd7-76s75-34k5-k34h-k3j4h5k3j4h5 -> ../../sdb1
lrwxrwxrwx 1 root root  9 2007-06-14 08:23 s78ds67-sd635-34kj-34k5-sfb23478623c -> ../../sdb

The above command shows you all the Universally Unique Identifiers for your detected hard disks and partitions. (You can also visit the directory: cd /dev/disk/ to find other disk identification information, such as cable location and serial number.) Assuming that your second hard drive is sdb1, you'll want to use: /dev/disk/by-uuid/s7d7sd7-76s75-34k5-k34h-k3j4h5k3j4h5 going forward when creating mount points.

Now is a good time to decide where you want to mount your disk, the above solution told you /media/seconddrive that will work, but personally I think it makes much more sense to mount it in the actual mount directory: /mnt/ Of course I could be just talking crazy (you _can_ mount anywhere you want); KDE on the other hand will do all kinds of nice auto icon creation and such if you use /mnt/ so thats what I recommend (yes, I know you are using gnome; you made baby Jesus cry).

To make the folder you will be mounting type this in the shell: sudo mkdir /mnt/seconddrive

It will ask you for your root password (sudo = super do) and create the new empty folder at /mnt/seconddrive of course you can change "seconddrive" to be anything you want.

Next to tell the system to use the folder as a mount point: sudo mount /dev/disk/by-uuid/s7d7sd7-76s75-34k5-k34h-k3j4h5k3j4h5 /mnt/seconddrive

Replace the UUID from your own system, you should not have to give the type like in the above solution the mount command _should_ auto detect it. Now you should be able to go to /mnt/seconddrive in your favorite  file explorer and be using your second hard drive, a quick left click to compare free space between /mnt/seconddrive and /mnt/ can be used to verify your other drive is in use. If gnome doesn't make you nice drive icons, you can create links to /mnt/seconddrive on your desktop (left click drag drop).

To un-mount your hard drive use: sudo umount /mnt/seconddrive

If you turn off your computer, the drive will be un-mounted automatically, to make it permanent you need to edit /etc/fstab with a text editor as root. You should probably make sure the above worked before doing that... Since I am lazy, and you can probably figure out the rest by using the above info and googling fstab I leave you there.

*rant* If you are a window user, you should have went with KDE; gnome is more geared towards mac users. The gnome ideology seams to be "it's easier because you have limited options"; like how one button mouses are suppose to be easier than two button mouses.

[Darwin]

My Neanderthal brain is starting to caramelize nicely as well... I'd better get reading too!

[zridling]

Tonurics, thanks, and yes, naturally I like KDE better, but thought I'd learn something new with gnome. I'm off to try.

[Gothi[c]]

To automatically mount your second drive on boot, and/or have it accessible by users other than root, you can add a line to your /etc/fstab file

(to edit /etc/fstab as the root user you can enter a command like:

Code

sudo gedit /etc/fstab

)

Add following lines for an additional ext3 drive and an additional ntfs drive, for example:

Code

/dev/sdb1   /media/seconddrive ext3    uid=500,gid=500,user    0 0
/dev/sdc1   /media/windowsdrive ntfs    uid=500,gid=500,user   0 0

Adding these lines also lets you use 'shortcut' mount commands like:
  mount /media/seconddrive
or
  mount /media/windowsdrive

Remember the mount points (the directories in the /media folder) need to exist, and if they don't exist they need to be created (as described in previous posts).

Also remember to change /dev/sdb1 or /dev/sdc1 respectively with your hd and partition, you can find out the correct names by using the methods described in previous posts.

[zridling]

Since then, here's what I've done:

              ls -l /dev/disk/by-uuid/

which returned:

              total 0
              lrwxrwxrwx 1 root root 10 2007-06-14 04:36 6068b6ae-9b08-4ce9-a6fe-08add83228c0 -> ../../sda1

So I did the following:

              mkdir /mnt/2drive

Open fstab file and added this line:

              /dev/hdb1 /mnt/2drive ext3 defaults 0 0

__________________________________
I read this, but I didn't understand the following command:

              mount /dev/mapper/<other_thing> /<mountpoint_directory>

What is the "other thing"?

Oy, nothing. Maybe I should consider doing this under KDE as Tonurics suggests. Gnome is making my tiny dinosaur brain hurt.

[zridling]

Hmmm, Gothic, I'll be honest, this is really all above my head, as like before, I truly don't understand what you're talking about. I'm not at the point where I can grasp this right now. I pulled out a Ubuntu hacker book and input all their commands to no avail also. As Tonurics noted, I'd love to be able to save data to a "d-drive" using ext3 and never have to worry about losing the data if I go distro hopping (as I invariably will over the next year).

[Darwin]

I share your pain, Zaine. I haven't starte trying to understand the command line in linux yet - I'm a bit awed by it, and strangely excited - but I want to be able to devote some significant, uninterupted time to its study - with a 3 and a 5 year old, that's not going to happen soon! I have great hopes for the evenings in my tent in Belgium. I'll let the 20 year olds drink Belgian beer while I distract myself from my PhD dissertation with a linux manual. That actually sounds appealing, incredibly foolhardy, and sad all at once 

[zridling]

I really need to start at the beginning with an "Idiot's Guide" or something, to get a grasp of the whole picture of the file system and storage management in GNU/Linux. I'm going to reload either Ubuntu or Fedora 7 this weekend with KDE and see if it's easier. But I'm glad I'm doing this, because when I read other accounts of Windows users who have made the switch, they don't seem to chronicle the obstacles.

As I keep saying, it's enlightening not because I can't do it yet, but simply because it's different. I'll get there eventually!

[Laughing Man]

I have to say.. Google is a great help to me when trying to use Linux. I've found sites that help with the command line, and like Windows errors, putting in common problems in Linux or terminal responses can help you find a solution. I first tried Linux (as an actual jump into it.. not messing around with just a Live CD) thru Wubi by installing it to my laptop. Then I made a real Ubuntu install on my desktop. Though I had my fair share of difficulties (though that was setting up Beryl), I'm happy to say that it is easier for me in Linux then in Windows. For example, we have an HP Photosmart 2600 printer in our house. And for everyone's XP computer it's like a plague trying to use HP's drivers. I havent' found a way to connect the printer manually thru Windows (none of our computers are on a workgroup) but in Linux it took me less then a minute to install it. Linux recognized it and everything.

Same with my ethernet ports, logitech webcam, etc.. the only issue I have now is getting some extra keys on my keyboard to work and getting the mic on my headset to work.

[Gothi[c]]

typing in: man fstab
at the command prompt will give you lots of information explaining how that file works, in detail, but i'll have a shot at it,...

As you know, the concept of a C-drive, D-drive, or drive letters in general does not exist. In windows, hard drives, cd's and even floppy disks also have to be `mounted`, but all this goes on behind the scenes, and the user is unaware of it. Windows (and DOS) will automatically assign drive letters to any drive it finds, and automatically 'mount' the drive on these 'drives'.

In linux, a drive, partition, or filesystem( could be an .iso image too for example ) can be mounted in any directory, and drive letters don't exist.
When the kernel (the core of the operating system) starts up, it will first see if any parameters were given along with it's startup (there is a root parameter which you can pass to the kernel in a boot loader, to tell it which drive/partition/filesystem should be mounted as 'root' filesystem). When referring to the 'root' filesystem, I am referring to the filesystem on which the directory / and all it's subdirectories are located. After mounting this filesystem, it will continue booting up, running what is called 'init' scripts which start different programs required on startup. And it will also check the /etc/fstab file to see which other filesystems it must mount. So naturally this file is of great importance to linux.

Lets look at a typical fstab file:

Code

/dev/VolGroup00/LogVol00 /                      ext3    defaults        1 1
LABEL=/boot             /boot                   ext3    defaults        1 2
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
tmpfs                   /dev/shm                tmpfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0
sysfs                   /sys                    sysfs   defaults        0 0
/dev/sdb1   /media/windows ntfs    uid=500,gid=500,user                  0 0
/dev/cdrom  /media/cdrom   iso9660 ro,user,noauto,unhide,uid=500,gid=500 0 0
/dev/VolGroup00/LogVol01 swap                   swap    defaults        0 0

The first column on each line, tells linux where to FIND the filesystem. Typically this will be something like /dev/sdb1 or /dev/hda1 etc,... (SATA drives are labeled as sda,sdb,sdc,etc,... IDE harddrives are labeled as hda,hdb,sdc,etc,... followed by the partition number)
The second column on each line tells linux where to MOUNT the filesystem. This is where you will find the files on that particular partition.
The third column on each line tells linux what TYPE of filesystem it is. (eg: ext2, ext3, ntfs, fat32, etc,...)
the Fourth column is for any additional OPTIONS you with to pass when mounting the filesystem (such as whether or not it should be allowed for regular (non-root) users to mount the partition, and what the default file permissions would be.
The last two columns (0 0 or 0 1 or 1 1 etc) are parameters telling how frequently that particular filesystem should be checked for errors on startup.

The particular example above may look a bit strange, because it uses LVM (Logical Volume Management) (see http://en.wikipedia.org/wiki/Logical_volume_management ) This is why you see stuff like the volgroup lines in there.

The devpts, tmpfs, procfs, and sysfs mount points are special directory trees containing information on running processes, hardware, temporary files, etc,...
For example, when you type the following command:

cat /proc/cpuinfo

Various information about your CPU will be shown. This just goes to show that ANYTHING can be treated as a filesystem and can be mounted.

I really hope this clears up at least a little bit,... Please be brave, strong, and don't be intimidated by any of this to stop learning! It really isn't half bad once you get the hang of it! I understand it's easy to be overwhelmed, because there are vast culture differences between Windows and Linux. There may or may not be some GUI applications out there that update the fstab file automatically, but I still think it's important to know what goes on behind the GUI, because at least then you know what to do if the GUI doesn't work

[Gothi[c]]

You're probably better of using fdisk to determine what the name of the device of your second drive is, Zaine, because it shows more information about the filesystem... eg:

Code

sudo fdisk -l
Password:

Disk /dev/sda: 250.0 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          13      104391   83  Linux
/dev/sda2              14       30401   244091610   8e  Linux LVM

Disk /dev/sdb: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *           1       19456   156280288+   7  HPFS/NTFS

As you can see, it also shows whether or not a filesystem is NTFS or ext3 or whatever else. (I use LVM though)
So if i wanted to add a line for my windows drive, I know windows uses NTFS, so i know the device would be sdb1 so the line to add in fstab, would have /dev/sdb1 in it's first column.

[Edvard]

Zaine: Maybe it is easier to imagine taking a disk labeled '/dev/somedisk' and plugging it into a directory labeled '/mnt/somefolder'. That's the dirty basics of what you are doing. You can't just access the disk as it is, it has to have a place to sit so it can interact with you.
In windows it would be something like IDE (or SATA) plug-in #1 "mounted" at C:/

If you're up for more reading, go here: http://www.tldp.org/guides.html

That first book "Introduction to Linux" is a good one. Read the chapter on filesystem management and the 'mount' command.

Darwin: The same goes for you, but check out the "GNU/Linux Command Line Tools Summary" and "BASH Guide for Beginners". There are a lot of tricky things going on in that little black box that whips the pants off cmd.exe.

Also check out Linux 101 at Linux.org: http://www.linux.org/lessons

For further brain melting, check out why the device filesystem underwent radical change between kernel 2.4 and 2.6:
http://www.kroah.com/linux/talks/ols_2003_udev_paper/Reprint-Kroah-Hartman-OLS2003.pdf
I like the idea of a dynamic /dev directory that lists only those devices detected, but all of a sudden all my hard drives are detected and mounted as scsi devices (for example, my shared drive, formerly /dev/hdb1 is now /dev/sdb1) ????

Tonurics: thanks for the tip on mounting a disk by UUID. An update breaking my mountpoint is exactly what happened. I fixed it in /etc/fstab as I described above, but I've been worrying about what will happen next time.

[Darwin]

Thanks Edvard, that explanation helped me, a bit, anyway!

[Tonurics]

That is weird the system only reported the one disk UUID... I still recommend trying to use the virtual symbolic links since they should never change between distributions or kernel updates.

I don't like it as much as it goes by the disk serial number but use this: ls -l /dev/disk/by-id/

It should out put something like this:

lrwxrwxrwx 1 root root  9 2007-06-19 08:41 scsi-1ATA_ST3160021A_5KJ2348LN -> ../../sdb
lrwxrwxrwx 1 root root 10 2007-06-19 08:41 scsi-1ATA_ST3160021A_5KJ2348LN-part1 -> ../../sdb1
lrwxrwxrwx 1 root root  9 2007-06-19 08:41 scsi-1ATA_ST3160022A_5VX84HJB -> ../../sda
lrwxrwxrwx 1 root root 10 2007-06-19 08:41 scsi-1ATA_ST3160022A_5VX84HJB-part1 -> ../../sda1
lrwxrwxrwx 1 root root 10 2007-06-19 08:41 scsi-1ATA_ST3160022A_5VX84HJB-part2 -> ../../sda2
lrwxrwxrwx 1 root root 10 2007-06-19 08:41 scsi-1ATA_ST3160022A_5VX84HJB-part5 -> ../../sda5

You'll need to identify the first partition on your second disk, in my cause that is scsi-1ATA_ST3160021A_5KJ2348LN-part1 which you'll want to use in place of hdb1 (sdb1 in my case).

Since you should already have the /mnt/2drive folder in place, your next command would be (change the disk id to match yours): sudo mount /dev/disk/by-id/scsi-1ATA_ST3160021A_5KJ2348LN-part1 /mnt/2drive

And you should be able to read and write to your second disk by going to /mnt/2drive.

For your fstab you would put (again use your disk id): /dev/disk/by-id/scsi-1ATA_ST3160021A_5KJ2348LN-part1 /mnt/2drive ext3 defaults 0 2

That should be it. I don't know where you are getting the rest of your information from but /dev/mapper/ is a container for _special_ file systems, such as in the case of on the fly encryption using luks, you would unlock your encrypted disk and have luks create a virtual device in /dev/mapper/ for you to mount with (as if it was a normal hard drive).

Even by switching to KDE your keystrokes here for mounting disks would be the same... However, I know Kubuntu has a easy to use GUI file system management tool similar to the one in windows that would let you do all of this without having to use the shell or edit fstab manually. Since you are just getting started with learning Linux, it might be better for you to stick with GUI tools for these sort of processes. The worst thing is for you to get needlessly frustrated with trying to learn a small manual process when there are tools to do this for you, and ultimately have a negative experience. Last time I'll say it, but to reiterate my KDE suggestion, if you are a windows user, KDE is still a world of difference but with a similar methodology. Personally (not to start a flame war of anything), I think gnome looks great with wonderful fonts and themes, but mind numbingly irritating to use.

Since then, here's what I've done:

              ls -l /dev/disk/by-uuid/

which returned:

              total 0
              lrwxrwxrwx 1 root root 10 2007-06-14 04:36 6068b6ae-9b08-4ce9-a6fe-08add83228c0 -> ../../sda1

So I did the following:

              mkdir /mnt/2drive

Open fstab file and added this line:

              /dev/hdb1 /mnt/2drive ext3 defaults 0 0

__________________________________
I read this, but I didn't understand the following command:

              mount /dev/mapper/<other_thing> /<mountpoint_directory>

What is the "other thing"?

Oy, nothing. Maybe I should consider doing this under KDE as Tonurics suggests. Gnome is making my tiny dinosaur brain hurt.

[Tonurics]

Sorry didn't see your reply there!

Don't ask me why, but as I understand it going forward all disks are doing to be treated as scsi; you'll have sd* instead of hd* and everyone will be encouraged to use the new UUID system. So stick with them and you shouldn't have any problems going forward.

[For future reference.] As for your fstab, you should just be able to put the UUID, like so:

UUID=34hj34h-34jhg-434h-8345-k3h434k5hkjh / ext3 defaults 0 0

Instead of having to use the full symbolic link path. The mount command hasn't been updated with UUID "automagic" yet, which is why I told zridling to use to full paths above.

Tonurics: thanks for the tip on mounting a disk by UUID. An update breaking my mountpoint is exactly what happened. I fixed it in /etc/fstab as I described above, but I've been worrying about what will happen next time.