This is Alan Pope with the tenth screencast in the Ubuntu Month of Screencasts
All the screencasts in this month can be downloaded for free from our website,
which is screencasts.ubuntu.com
In this screencast we are going to look at installing Ubuntu again,
but this time we are going to use the alternate CD.
When you boot up the alternate CD
you get a display that looks a little bit like this.
And we've got a number of options you can choose with arrow keys
and press enter to select them.
We also have some function keys along the bottom.
Pressing F1 gives us some on-line help.
Pressing F2 allows us to change the language that the system boots up in.
F3 allows you to change the keyboard layout, which I'll change to United Kingdom.
F4 allows you to change the resolution of the screen,
which is useful if maybe your display or your video card doesn't support the resolution
that this CD boots up in.
And F5 gives you some accessibility options.
For example if your eyesight isn't great
or you can't read the dark brown text on a black background,
then you can change to one of these other options.
F6 we will look at in just a minute.
So the list of options we have, the first one is "Install in text mode".
Now the difference between this and the live CD is,
this CD (the alternate CD) doesn't boot into a live environment.
It can only be used to install a system or recover a broken system.
The "OEM install" option allows you to install the system,
but leave some of the questions out for the user to answer on the first boot up.
This is often used by OEMs, Original Equipment Manufacturers, PC builders
The next one is an option to "Install a command line system".
We might look at this in a later screencast.
but in a nutshell this creates a installation that has no graphic user interface, no GUI.
So you might want to use that as a server
or you could use it as a way to install a base system
and then on top of that install Kubuntu, Xubuntu or Edubuntu.
So I have an Ubuntu CD, but I could actually install a command-line system
and then install Kubuntu on top of that.
The next option is "Check CD for Defects"
and this is useful if you have downloaded a CD and burned it yourself,
just to make sure it's not got any errors.
"Rescue a broken system", well that allows you to use the command-line to
fix problems that may occur in a broken system
"Memory test" does a check on the physical memory in your computer,
which can often fail.
And "Boot from first hard disk" is useful
if you've manged to mess up the boot setup on your hard drive.
If you press F6, you get this list of boot options.
Now these are useful in that you could modify them
to change the way the system boots up from this alternate CD.
But also sometimes people will suggest that you remove options
like I just removed the word quiet there.
If you remove quiet it doesn't make a lot of noise,
it just means that the boot up is more verbose.
And you may also get asked to add parameters like this noapic, noacpi,
to work around problems with your hardware.
This is usually recommended by experts when diagnosing problems
I'll just press enter in order to boot into the installer.
Now to navigate around the installer is pretty simple,
you use the arrow keys up and down, press enter to select
and you can use tab to move between fields.
So if there's multiple fields on the screen you just tab between them.
Use the arrows, press enter when you are done.
So I'm going to choose English and my country is United Kingdom.
Now there's actually not very many questions it's going to ask.
But what I'm going to do is redo a section of this a number of times
to show you what it looks like under different scenarios
And I'll explain more about that when we come to it.
But there are very few questions it asks during the installation.
In fact this video makes it look a lot more complicated than it really is,
because I keep going backwards and forwards
to show you lots of different options.
Now on the CD, there's a repository of packages.
and in fact you can use this CD to upgrade from a previous release of Ubuntu.
Say for example if you were running 7.04 and you wanted to upgrade to 7.10,
you could use the alternate CD because it is a repository on a CD.
You could use that repository to upgrade the packages from.
Incidentally you can't do that with a live CD,
because of the way the live CD works, it doesn't actually have a repository on it.
I has a live running environment, which is then copied to the hard disk.
But the alternate CD we are using today has a repository on it,
so it can be used for upgrades.
Now it's just going to do a little connection to the network,
and it asks me for a hostname.
So this is the name of the computer, what do I want to call it on the network.
What would other computers see my system as and I'm going to call it gutsydemo.
It's worth noting I'm using Ubuntu Gutsy, which I wouldn't recommend anyone use right now.
Because this is still under development,
it's not out for another month or so until October.
After October of course, you can use Gutsy, version 7.10.
Because it will be the current stable version.
Now this is the next bit that I am going to do multiple times
The partitioner, I will first of all show you the two really easy ways to set up partitioning.
If you are not interested in the complex ways to do with RAID,
then skip forward to about 22 mins into this video.
So the first option we have is "Guided - use entire disk".
Now what this means is it's going to carve the disk up in the recommended way.
It's going to create a chunk of space to store your files
and a chunk of space for swap.
The second option uses Logical Volume Management, which is very very useful
if you ever think you might have to add more space to the system.
Using LVM is useful because you can add space to an existing partition.
And the third option is manual, which covers an awful lot of options actually.
So, the first one, if we were to use guided.
I've actually got three 10GB disks in this machine.
You can see they are called sda, a is the first disk.
sdb is the second disk and sdc is the third disk.
They are all the same, they're all 10 GB disks.
And if I were to choose one of these disks, like the first one.
Remember I've chosen the easy option, guided partitioning.
All I've done is choose the disk I want to install Ubuntu on to
and if I've got multiple disks in the machine
and I've got other operating systems on the other disks.
you obviously I've got to be careful which disk I choose.
But it will tell me what partitions are already on the disk.
These happen to be completely blank disks, there's no partitions,
no operating system on them at all, they're completely blank.
So can see here it's figured out that it wants to create partition number one on sda.
and partition number five for swap
So partition 1 will have all my files in it and partition 5 will have swap
and that's it and all you do is just say yes and that's done.
So that's the very easy option of partitioning.
The second option here is use entire disk and setup LVM.
Now again it asks us which disk do you want to use
to install Ubuntu onto.
And I've chosen the first disk and again it goes away and does some calculations.
Now it's going to be a little bit different in this scenario,
because when you use LVM. LVM is a kind of layer on the disk
that allows you to do some rather funky things.
And you can see here it's saying, well before I can create the partitions
you need for your files,
we need to save the configuration of LVM first.
So it asks to write the changes to disk. so say yes.
And it writes the changes to do with LVM onto the disk.
Once that's done it then calculates the partitions that are going to be required.
and again the process is pretty much semi-automatic.
I've not really had an interaction other than saying yes
and choose which disk I want to install on to.
Now going into LVM, and subsequently RAID on this screencast
is a large subject that we don't really have the time to cover.
So I'll just tell you about the basics and how great LVM is and what RAID is.
So now it comes back to a summary and if we look here,
we've got sda has a partition on it that has been created
and the partition is 255MB and it's for the boot partition.
Where the boot files go, when it boots up it needs access to that area.
Now that area, there's a limitation, that area can't live on an LVM volume.
So it's created a partition for boot which isn't in LVM.
and then immediately after that you can see there is a 10.5GB partition for LVM.
So the boot partition is created first, then this ~10GB chunk of space on the first disk
And into that LVM, we've got two further partitions.
We've got an EXT3 partition, which is where all my files would go.
EXT3 is the type of file system, it's the way the files are laid out on disk.
And that's my root partition,
the slash on the end of that line means it's my root partition, top level of the disk.
And then we've got a 500MB swap partition.
You can think of the swap simplistically as an extension of the RAM in your machine.
And you'll notice it hasn't touched these two disks down here, sdc and sdb.
And if I were to run out of space, subsequently down the line,
maybe in three months time, I've filled up this disk..
I could use LVM to extend that partition, on these other two disks.
So I could utilize the free space, on those two disks,
in order to make my 10GB EXT3 partition larger.
Now a word of warning, if you do that you spread LVM across a number of disks,
if any one of those disks fails the chances are you won't be able to recover the data,
there is no resilience there.
So let's look at another option for partitioning and that is using RAID.
Now RAID we're looking at here is software RAID.
And by manually partitioning, what we are going to do is manually configure
these disks so that we can spread the data across the disks
in such a way that we have some resilience.
Now what I'm doing now is just pressing enter on each of the disks
because they are blank brand new disks, when I press enter on the disks it says
well there's no partition table these have never been used these disks.
so I need to create a partition table and when I press enter
on sdb we get this dialog that asks me do you want to create the partition table
and I say yes.
And then we can see there is 10GB of free space on the disk, an empty partition.
I do the same thing on the last disk, so I've now got three disks, three physical disks
and those three physical disks each one has 10GB of free space.
If I then press enter on the free space,
I can do something with that free space, like create a new partition.
So now we get into the advanced manually partitioning your disks.
So it's a 10.7GB disk and what I am going to do is take off the 0.7
and make a partition that is 10GB in size, just to make it nice and easy.
So the disk is 10.7GB and I'm going to create a 10GB primary partition,
and you can have up to four primary partitions
and I'm going to make it at the beginning of the disk.
You can make the partition at the end of the disk if you want to,
you can arrange the partitions however you like.
It then asks me what I'm going to use that partition for.
And if I go up to the use as field
so that instead of being EXT3, the normal file system,
If I go down near the bottom, you can see, if I use physical volume for RAID
Then what I'm saying is I want to create a partition, but I don't want to put any files in that yet.
I want to use that partition for RAID.
So I'm going to set-up some kind of RAID solution.
I hit done and when we come back,
you can now see we've got one primary partition for RAID on that first disk.
and we've also got 700MB of free space on that disk.
If we now do the same thing on the second disk.
Just click on the free space.
Specify 10GB primary partition at the beginning of the disk.
And worth noting that I'm making these the same size on all three disks
in order to implement a RAID solution of redundancy across multiple disks.
The partitions that you use under software RAID on Linux need to be the same sizes
The physical disks underneath don't need to be the same sizes,
but the partitions you create do.
So I could have a 10GB, a 20GB and a 40GB disk,
But actually just create three 10GB partitions for RAID, one on each disk.
I'd end up with some empty space on the 20GB and 40GB disks,
but it's certainly something you can do.
So now what we've got,
if I change this last disk to use it as a partition for RAID.
Sorry a physical volume for RAID.
What we should now have is three partitions each of 10GB
one on each disk, ready for me to configure software RAID.
Now there are three levels of RAID that are supported under Linux.
RAID 0, RAID 1 and RAID 5, and if I go to configure software RAID.
I think it will ask me to write the changes,
I've just made quite a few changes, so yes
it asks me to write those changes to the disks.
So before we can move on to the next step,
we need to flush out what we've done to disk, so I say yes.
And then it will ask me what I want to do,
Now I want to create an MD device, a Multi Disk device.
And these are RAID devices under Linux.
And as I said, I've got three options, once I choose create MD device,
I can choose to create a RAID 0, RAID 1 or RAID 5 device.
Explaining the difference between RAID 0, 1 and 5 is
and the pros and cons of each, is a bit beyond this screencast.
So I'll put some links on the website,
as to where you can find out more about these different levels
and which one is right for you.
I'll just show you how you actually create them
and a couple of differences between them.
So the first one we are going to choose is RAID 5.
Now you see here it says you need a minimum of three devices,
well that's good, because we've got three physical volumes for RAID.
And it asks me how many do I want in the array.
I could have more than three, but I'm going to have three.
And now it asks me how many spare devices
and a spare device will be used if one of the drives fails.
So if one of the volumes fails on one of the drives, it will bring in the spare
Now I haven't got more than three, so I don't have enough for a spare.
Now it's asking me, okay of the disk that you've got, we can see you've got
sda1, sdb1 and sdc1.
These are the physical volumes for RAID that we created earlier
and it wants me to tick each one, I just used the space bar there
to tick each one that I want to be in this RAID 5 array.
I might have ten disks or twenty disks and I just want to choose the ones I want to include.
That's it, that's all you have got to do to create your RAID 5 array.
Now lets have a look at the same thing again, that I've reset everything now.
and we'll create a RAID 1 set.
With a RAID 1 set we can put two disks in.
Exactly two disks, into our RAID 1 set.
RAID 1 will be a mirror so we'll end up with the same data
on both of those two disks.
And it asks me how many spare devices.
Now we've got a three disks, so I can use two disks for the RAID 1 mirror
and then one for a spare.
So that in the event that one of the first two disks fails,
that third disk can be brought on-line.
And when I press continue,
what it will do is in the event that one of the disks fails
it will start synchronizing with the spare.
Now it's asking me which of the three are going to be the two disks
that are going to be in the RAID 1 set.
So there are three RAID devices, that we created earlier, sda1, sdb1 and sdc1.
and I can choose any two of them to be the two primary active partitions.
And now it asks me which one is going to be the spare.
There's only one left, so this one is going to be the spare
for my RAID 1 multi disk device.
Note is does actually mention you can create a mirrored set with only one disk,
and have the other disk as missing.
you can do that and add it later on.
So if you've only got one disk, you can start with one
and then add the second one later on when you buy one.
The third option is RAID 0, so again we've reset, start from scratch.
RAID 0, we just add all of the devices into the RAID 0 array.
Now with RAID 0 we are striping across the disks,
so when you are striping we have no resilience there.
If a disk fails, we've lost data.
So in my set-up on my desktop PC, I actually use RAID 1
And in this example for the rest of this screencast I'm using RAID 1.
So I've set-up RAID 1, so I have got two of the disks
as primary active and the third one is the spare
just in case one of the two disks fails.
and when you click finish within multi disk setup,
it takes you back to the partitioning screen.
and you can see here we've got a RAID 1 device of 10GB,
software RAID and it's empty, it's not currently being used.
And that's made up of the disks below, each having a 10GB volume for RAID.
Now I press enter on that device.
It says what do you want to use it for?
So now that I have created my RAID 1 device I can choose "Use as"
and use it as an EXT3 file system and this is going to be the file system
into which I'm going to install Ubuntu.
Some people have multiple file systems on their computers
They might have one for root, one for boot, one for var, one for temp,
I generally just have one for root and maybe also one for home.
If you watched the previous screencast to this you will see how I set up
having two partitions, one for root and one for home.
So that is done, we've now got a root partition.
You can see the / there means the root, the top directory on the directory tree,
is an EXT3 journaled file system, nice and robust and reliable and it's 10GB in size.
Now the one other thing I need to add before I continue with the install
is some swap space.
So I'm going to choose one of these 700MB of free space.
and just press enter, create a new partition
and use all that space, all the 732MB as a primary partition for swap.
Remember swap is this area of disk that's used
as a kind of extension of the memory that your system has.
And so I'm going to say how to use this partition, use it as swap area,
And when I hit done setting up the partition
it takes me back to the partitioning screen.
And we should see a summary of everything.
So now I've got partition 1, at the top is the RAID partition
And in this partition 2 is a swap partition.
I could if I wanted to use the 732MB of free space on sdb and sdc,
the other two disks, I could use that as swap space as well.
But I'm not going to, if I run out I can always add that later on.
There's a nice partitioning tool in Ubuntu called gparted.
A graphical environment that allows you to do pretty much
everything that you're seeing here.
But after you've installed the system.
It's not wise to make changes to the system while it's running though.
I think gparted will stop you doing that.
But if you were to boot off of the live CD, you could then run gparted
and rearrange the partitions and juggle things around on your hard disk.
So the final summary here is you have got a RAID device,
that's going to be formatted as EXT3
and then you've got a normal partition on the first disk sda as swap
So it goes off and does various bits and bobs
including formatting the partitions
And while it's formatting the partitions if you're using any form of RAID in the background
the kernel will be synchronizing the disks.
So as you're writing changes to the disk it will be making sure that
those disks are kept in sync.
And if for any reason you've got one disk is missing
or you've taken one disk out of the array.
Later on when you put it back in, it will re-synchronize that disk
or you can forcibly re-synchronize that disk.
Now this question here is interesting, it asks me is the local clock on system,
the clock inside my computer set to UTC.
This normally doesn't cause a problem, but it can be an issue
if you dual boot between Windows and Linux,
because I believe Windows thinks that or assumes that the physical clock in the machine
is set to local time, wherever you may be.
So that could be European time or some time in some timezone in America or wherever you are.
As Linux according to this screen, assumes the local clock to be UTC.
So it's worth noting that.
Next it asks for a user, now the first user you create in Ubuntu
is an administrative account.
You can create further accounts as well.
So it's going to create a user id called alan in this case and it's going to ask me for a password.
You can create new accounts, you can change the rights of this account.
But usually the first person, the first user created is the administrative account.
And then can then be used to do various administrative tasks on the system.
Now it's now moving on to do the actual installation,
So we've got the partitioning done, the formatting is done.
It's asked pretty much all the questions it's going to ask.
I think there's only one more question it's going to ask.
Well, it's going to ask two questions if you count "press continue to reboot".
Now what it's doing right now is installing the base system.
Now a base system is just a basic, lean set of packages.
And this isn't going to take too long.
There's a whole bunch of packages that are very curious names that don't make much sense
to most people, in the base system, other than developers.
you might spot things you may have heard of.
But once this has finished installing the base system,
It then scans the repository that's on the CD-ROM,
Remember I said the alternate CD has a repository
of the packages that get installed by the alternate CD.
And once this base system has finished installing
and we have got a basic pretty usable system on the hard disk.
But it will have no GUI, no graphical applications,
there will be no word processor or browser or anything like that.
It's really really basic, a basic system, hence being called a base system.
Once that's finished it will go off and scan the repository
And then start installing the actual applications
that you're probably going to use on a desktop environment.
So you might start seeing package names at this stage, that may be more familiar to you.
Now here is the question that it asks you, the last question
which is what screen resolution do you want
the X Windowing System, which is simply put the graphical environment.
What resolution do you want the graphical environment to run at?
And you tick whatever the supported resolutions are
and it configures the server to run at that resolution.
And in fact this version of Ubuntu, remember I said is 7.10,
which is not released yet, so I wouldn't recommend people run it right now.
But after October 19th, I think it comes out, you should be okay to run it.
It has a new feature called bulletproof X
One of the problem with previous releases of Ubuntu is that
if the X windowing system can't do what you've requested,
you request a certain situation, a driver or resolution that it can't do,
it just fails and you get no graphical environment, you are dropped to a text console
This version of Ubuntu contains something called bulletproof X,
which should still be able to start the graphical environment.
with some basic settings, to allow you to then re-configure the graphical environment,
like a kind of safe mode, if you like.
It's nearly at the end, it's installed Grub, which is the boot loader,
the menu you get at the start of booting up your PC.
If you have multiple operating systems, then it will list multiple operating systems in the boot menu
So it's just installing that.
Cleaning up a little bit.
Creating my user and setting the password.
and we are pretty much done.
There we go, spits the CD out and you then reboot.
When you reboot, you should, if all goes well, be taken to the graphical logon screen.
So if we hit continue now, we should get the logon screen.
There we go, so this is the system that I just installed with that alternate CD.
And it did "Just Work".
And once I enter my user id and password, we get the graphical desktop.
There we go and we've covered some of the other elements on the desktop
in some of the previous screencasts.
So if you visit our website you will find screencasts about what the desktop does.
and what the main feature of the desktop are
and we've also done screencasts about the Applications menu, Places and System
and I would recommend watching some of those after installing.
There's a load of updates to apply as well, 292 on this system.
And there's a few other useful little tools that are pre-installed and set-up..
But once you've installed, have a play.
Hope that was useful.
You will find all the screencasts in the Month of Screencasts available for free on our website,
which is screencasts.ubuntu.com.