Difference between pages "Awk by Example, Part 1" and "Install/ru/Partitioning"

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{{Article
<noinclude>
|Author=Drobbins
{{InstallPart|процесс разбиения диска и создания файловых систем}}
|Next in Series=Awk by Example, Part 2
</noinclude>
}}
=== Подготовка жесткого диска ===
 
В этой части  мы научимся различным способам установки Funtoo Linux -- и загрузки с -- жесткий диск.
 
==== Введение ====
 
В прежние времена существовал лишь один способ загрузить PC-совместимый компьютер. Все наши дектопы и сервера имели стандартный PC BIOS, все наши харды использовали MBR и были разбиты используя схему разбивки MBR.  Вот как это все было и нам это нравилось!
 
Затем появились EFI и UEFI,  встроенные программы нового образца наряду со схемой разбивки GPT, поддерживающая диски размером более 2.2TБ. Неожиданно, нам стали доступны различные способы установки и загрузки Линукс систем . То, что было единым методом, стало чем-то более сложным.
 
Let's take a moment to review the options available to you for configuring a hard drive to boot Funtoo Linux. This Install Guide uses, and recommends, the old-school method of BIOS booting and using an MBR. It works and (except for rare cases) is universally supported. There's nothing wrong with it. If your system disk is 2TB or smaller in size, it won't prevent you from using all of your disk's capacity, either.
 
But, there are some situations where the old-school method isn't optimal. If you have a system disk >2TB in size, then MBR partitions won't allow you to access all your storage. So that's one reason. Another reason is that there are some so-called "PC" systems out there that don't support BIOS booting anymore, and force you to use UEFI to boot. So, out of compassion for people who fall into this predicament, this Install Guide documents UEFI booting too.
 
Our recommendation is still to go old-school unless you have reason not to. The boot loader we will be using to load the Linux kernel in this guide is called GRUB, so we call this method the '''BIOS + GRUB (MBR)''' method. It's the traditional method of setting up a PC-compatible system to boot Linux.
 
If you need to use UEFI to boot, we recommend not using the MBR at all for booting, as some systems support this, but others don't. Instead, we recommend using UEFI to boot GRUB, which in turn will load Linux. We refer to this method as the '''UEFI + GRUB (GPT)''' method.
 
And yes, there are even more methods, some of which are documented on the [[Boot Methods]] page. We used to recommend a '''BIOS + GRUB (GPT)''' method but it is not consistently supported across a wide variety of hardware.
 
'''The big question is -- which boot method should you use?''' Here's how to tell.
 
;Principle 1 - Old School: If you can reliably boot System Rescue CD and it shows you an initial light blue menu, you are booting the CD using the BIOS, and it's likely that you can thus boot Funtoo Linux using the BIOS. So, go old-school and use BIOS booting, ''unless'' you have some reason to use UEFI, such as having a >2.2TB system disk. In that case, see Principle 2, as your system may also support UEFI booting.
 
;Principle 2 - New School: If you can reliably boot System Rescue CD and it shows you an initial black and white menu -- congratulations, your system is configured to support UEFI booting. This means that you are ready to install Funtoo Linux to boot via UEFI. Your system may still support BIOS booting, but just be trying UEFI first. You can poke around in your BIOS boot configuration and play with this.
 
;What's the Big Difference between Old School and New School?: Here's the deal. If you go with old-school MBR partitions, your <code>/boot</code> partition will be an ext2 filesystem, and you'll use <code>fdisk</code> to create your MBR partitions. If you go with new-school GPT partitions and UEFI booting, your <code>/boot</code> partition will be a vfat filesystem, because this is what UEFI is able to read, and you will use <code>gdisk</code> to create your GPT partitions. And you'll install GRUB a bit differently. That's about all it comes down to, in case you were curious.
 
;Also Note: To install Funtoo Linux to boot via the New School UEFI method, you must boot System Rescue CD using UEFI -- and see an initial black and white screen. Otherwise, UEFI will not be active and you will not be able to set it up!
 
{{Note|'''Some motherboards may appear to support UEFI, but don't.''' Do your research. For example, the Award BIOS in my Gigabyte GA-990FXA-UD7 rev 1.1 has an option to enable UEFI boot for CD/DVD. '''This is not sufficient for enabling UEFI boot for hard drives and installing Funtoo Linux.''' UEFI must be supported for both removable media (so you can boot System Rescue CD using UEFI) as well as fixed media (so you can boot your new Funtoo Linux installation.) It turns out that later revisions of this board (rev 3.0) have a new BIOS that fully supports UEFI boot.  This may point to a third principle -- know thy hardware.}}
 
==== Old-School (BIOS/MBR) Method ====
 
{{Note|Use this method if you are booting using your BIOS, and if your System Rescue CD initial boot menu was light blue. If you're going to use the new-school method, [[#New-School (UEFI/GPT) Method|click here to jump down to UEFI/GPT.]]}}
 
===== Preparation =====
 
First, it's a good idea to make sure that you've found the correct hard disk to partition. Try this command and verify that <code>/dev/sda</code> is the disk that you want to partition:
 
<console>
# ##i##fdisk -l /dev/sda
 
Disk /dev/sda: 640.1 GB, 640135028736 bytes, 1250263728 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: gpt
 
 
#        Start          End    Size  Type            Name
1        2048  1250263694  596.2G  Linux filesyste Linux filesystem
</console>
 
Now, it's recommended that you erase any existing MBR or GPT partition tables on the disk, which could confuse the system's BIOS at boot time. We do this using <code>sgdisk</code>:
{{fancywarning|This will make any existing partitions inaccessible! You are '''strongly''' cautioned and advised to backup any critical data before proceeding.}}
 
<console>
# ##i##sgdisk --zap-all /dev/sda
 
Creating new GPT entries.
GPT data structures destroyed! You may now partition the disk using fdisk or
other utilities.
</console>
 
This output is also nothing to worry about, as the command still succeded:
 
<console>
***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory.
***************************************************************
</console>
 
===== Partitioning =====
 
Now we will use <code>fdisk</code> to create the MBR partition table and partitions:
 
<console>
# ##i##fdisk /dev/sda
</console>
 
Within <code>fdisk</code>, follow these steps:
 
'''Empty the partition table''':
 
<console>
Command (m for help): ##i##o ↵
</console>


== An intro to the great language with the strange name ==
'''Create Partition 1''' (boot):


=== In defense of awk ===
<console>
In this series of articles, I'm going to turn you into a proficient awk coder. I'll admit, awk doesn't have a very pretty or particularly "hip" name, and the GNU version of awk, called gawk, sounds downright weird. Those unfamiliar with the language may hear "awk" and think of a mess of code so backwards and antiquated that it's capable of driving even the most knowledgeable UNIX guru to the brink of insanity (causing him to repeatedly yelp "kill -9!" as he runs for coffee machine).
Command (m for help): ##i##n ↵
Partition type (default p): ##i##↵
Partition number (1-4, default 1): ##i##↵
First sector: ##i##↵
Last sector: ##i##+128M ↵
</console>


Sure, awk doesn't have a great name. But it is a great language. Awk is geared toward text processing and report generation, yet features many well-designed features that allow for serious programming. And, unlike some languages, awk's syntax is familiar, and borrows some of the best parts of languages like C, python, and bash (although, technically, awk was created before both python and bash). Awk is one of those languages that, once learned, will become a key part of your strategic coding arsenal.
'''Create Partition 2''' (swap):


=== The first awk ===
<console>
Let's go ahead and start playing around with awk to see how it works. At the command line, enter the following command:
Command (m for help): ##i##n ↵
Partition type (default p): ##i##↵
Partition number (2-4, default 2): ##i##↵
First sector: ##i##↵
Last sector: ##i##+2G ↵
Command (m for help): ##i##t ↵
Partition number (1,2, default 2): ##i## ↵
Hex code (type L to list all codes): ##i##82 ↵
</console>


<console>$##i## awk '{ print }' /etc/passwd</console>
'''Create the root partition:'''


You should see the contents of your /etc/passwd file appear before your eyes. Now, for an explanation of what awk did. When we called awk, we specified /etc/passwd as our input file. When we executed awk, it evaluated the print command for each line in /etc/passwd, in order. All output is sent to stdout, and we get a result identical to catting /etc/passwd.
<console>
Command (m for help): ##i##n ↵
Partition type (default p): ##i##↵
Partition number (3,4, default 3): ##i##↵
First sector: ##i##↵
Last sector: ##i##↵
</console>


Now, for an explanation of the { print } code block. In awk, curly braces are used to group blocks of code together, similar to C. Inside our block of code, we have a single print command. In awk, when a print command appears by itself, the full contents of the current line are printed.
'''Verify the partition table:'''


Here is another awk example that does exactly the same thing:
<console>
Command (m for help): ##i##p


<console>$##i## awk '{ print $0 }' /etc/passwd</console>
Disk /dev/sda: 298.1 GiB, 320072933376 bytes, 625142448 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x82abc9a6


In awk, the $0 variable represents the entire current line, so print and print $0 do exactly the same thing. If you'd like, you can create an awk program that will output data totally unrelated to the input data. Here's an example:
Device    Boot    Start      End    Blocks  Id System
/dev/sda1          2048    264191    131072  83 Linux
/dev/sda2        264192  4458495  2097152  82 Linux swap / Solaris
/dev/sda3        4458496 625142447 310341976  83 Linux
</console>


<console>$##i## awk '{ print "" }' /etc/passwd</console>
'''Write the parition table to disk:'''


Whenever you pass the "" string to the print command, it prints a blank line. If you test this script, you'll find that awk outputs one blank line for every line in your /etc/passwd file. Again, this is because awk executes your script for every line in the input file. Here's another example:
<console>
Command (m for help): ##i##w
</console>


<console>$##i## awk '{ print "hiya" }' /etc/passwd</console>
Your new MBR partition table will now be written to your system disk.


Running this script will fill your screen with hiya's. :)
{{Note|You're done with partitioning! Now, jump over to [[#Creating filesystems|Creating filesystems]].}}


=== Multiple fields ===
==== New-School (UEFI/GPT) Method ====
Awk is really good at handling text that has been broken into multiple logical fields, and allows you to effortlessly reference each individual field from inside your awk script. The following script will print out a list of all user accounts on your system:


<console>$##i## awk -F":" '{ print $1 }' /etc/passwd</console>
{{Note|Use this method if you are booting using UEFI, and if your System Rescue CD initial boot menu was black and white. If it was light blue, this method will not work.}}


Above, when we called awk, we use the -F option to specify ":" as the field separator. When awk processes the print $1 command, it will print out the first field that appears on each line in the input file. Here's another example:
The <tt>gdisk</tt> commands to create a GPT partition table are as follows. Adapt sizes as necessary, although these defaults will work for most users. Start <code>gdisk</code>:


<console>$##i## awk -F":" '{ print $1 $3 }' /etc/passwd</console>  
<console>
# ##i##gdisk
</console>


Here's an excerpt of the output from this script:
Within <tt>gdisk</tt>, follow these steps:
<pre>
halt7
operator11
root0
shutdown6
sync5
bin1
....etc.
</pre>
As you can see, awk prints out the first and third fields of the /etc/passwd file, which happen to be the username and uid fields respectively. Now, while the script did work, it's not perfect -- there aren't any spaces between the two output fields! If you're used to programming in bash or python, you may have expected the print $1 $3 command to insert a space between the two fields. However, when two strings appear next to each other in an awk program, awk concatenates them without adding an intermediate space. The following command will insert a space between both fields:


<console>$##i## awk -F":" '{ print $1 " " $3 }' /etc/passwd</console>
'''Create a new empty partition table''' (This ''will'' erase all data on the disk when saved):


When you call print this way, it'll concatenate $1, " ", and $3, creating readable output. Of course, we can also insert some text labels if needed:
<console>
Command: ##i##o ↵
This option deletes all partitions and creates a new protective MBR.
Proceed? (Y/N): ##i##y ↵
</console>


<console>$##i## awk -F":" '{ print "username: " $1 "\t\tuid:" $3 }' /etc/passwd</console>
'''Create Partition 1''' (boot):


This will cause the output to be:
<console>
<pre>
Command: ##i##n ↵
username: halt    uid:7
Partition Number: ##i##1 ↵
username: operator uid:11
First sector: ##i##↵
username: root    uid:0
Last sector: ##i##+500M ↵
username: shutdown uid:6
Hex Code: ##i##↵
username: sync    uid:5
</console>
username: bin      uid:1
....etc.
</pre>


=== External Scripts ===
'''Create Partition 2''' (swap):
Passing your scripts to awk as a command line argument can be very handy for small one-liners, but when it comes to complex, multi-line programs, you'll definitely want to compose your script in an external file. Awk can then be told to source this script file by passing it the -f option:


<console>$##i## awk -f myscript.awk myfile.in </console>
<console>
Command: ##i##n ↵
Partition Number: ##i##2 ↵
First sector: ##i##↵
Last sector: ##i##+4G ↵
Hex Code: ##i##8200 ↵
</console>


Putting your scripts in their own text files also allows you to take advantage of additional awk features. For example, this multi-line script does the same thing as one of our earlier one-liners, printing out the first field of each line in /etc/passwd:
'''Create Partition 3''' (root):
<pre>
BEGIN {
        FS=":"
}
{ print $1 }
</pre>
The difference between these two methods has to do with how we set the field separator. In this script, the field separator is specified within the code itself (by setting the FS variable), while our previous example set FS by passing the -F":" option to awk on the command line. It's generally best to set the field separator inside the script itself, simply because it means you have one less command line argument to remember to type. We'll cover the FS variable in more detail later in this article.


It is also possible to make the script directly executable, by placing a "#!/usr/bin/awk -f" at the top of the file, as follows:
<console>
<pre>
Command: ##i##n ↵
#!/usr/bin/awk -f
Partition Number: ##i##3 ↵
BEGIN {
First sector: ##i##↵
FS=":"
Last sector: ##i##↵##!i## (for rest of disk)
}
Hex Code: ##i##↵
{ print $1 }
</console>
</pre>
Next, the script must be made executable by setting the script file's execute bit:


<console>$##i## chmod +x myscript.awk</console>
Along the way, you can type "<tt>p</tt>" and hit Enter to view your current partition table. If you make a mistake, you can type "<tt>d</tt>" to delete an existing partition that you created. When you are satisfied with your partition setup, type "<tt>w</tt>" to write your configuration to disk:


Now, you should be able to execute the script as follows:
'''Write Partition Table To Disk''':


<console>$##i## ./myscript.awk myfile.in</console>
<console>
Command: ##i##w ↵
Do you want to proceed? (Y/N): ##i##Y ↵
</console>


=== The BEGIN and END blocks ===
The partition table will now be written to disk and <tt>gdisk</tt> will close.
Normally, awk executes each block of your script's code once for each input line. However, there are many programming situations where you may need to execute initialization code before awk begins processing the text from the input file. For such situations, awk allows you to define a BEGIN block. We used a BEGIN block in the previous example. Because the BEGIN block is evaluated before awk starts processing the input file, it's an excellent place to initialize the FS (field separator) variable, print a heading, or initialize other global variables that you'll reference later in the program.


Awk also provides another special block, called the END block. Awk executes this block after all lines in the input file have been processed. Typically, the END block is used to perform final calculations or print summaries that should appear at the end of the output stream.
Now, your GPT/GUID partitions have been created, and will show up as the following ''block devices'' under Linux:


=== Regular expressions and blocks ===
* <tt>/dev/sda1</tt>, which will be used to hold the <tt>/boot</tt> filesystem,
Awk allows the use of regular expressions to selectively execute an individual block of code, depending on whether or not the regular expression matches the current line. Here's an example script that outputs only those lines that contain the character sequence foo:
* <tt>/dev/sda2</tt>, which will be used for swap space, and  
* <tt>/dev/sda3</tt>, which will hold your root filesystem.


<pre>/foo/ { print }</pre>
==== Creating filesystems ====


Of course, you can use more complicated regular expressions. Here's a script that will print only lines that contain a floating point number:
{{Note|This section covers both BIOS ''and'' UEFI installs. Don't skip it!}}


<pre>/[0-9]+\.[0-9]*/ { print }</pre>
Before your newly-created partitions can be used, the block devices need to be initialized with filesystem ''metadata''. This process is known as ''creating a filesystem'' on the block devices. After filesystems are created on the block devices, they can be mounted and used to store files.


=== Expressions and blocks ===
Let's keep this simple. Are you using old-school MBR partitions? If so, let's create an ext2 filesystem on /dev/sda1:
There are many other ways to selectively execute a block of code. We can place any kind of boolean expression before a code block to control when a particular block is executed. Awk will execute a code block only if the preceding boolean expression evaluates to true. The following example script will output the third field of all lines that have a first field equal to fred. If the first field of the current line is not equal to fred, awk will continue processing the file and will not execute the print statement for the current line:


<pre>$1 == "fred" { print $3 }</pre>
<console>
# ##i##mkfs.ext2 /dev/sda1
</console>


Awk offers a full selection of comparison operators, including the usual "==", "<", ">", "<=", ">=", and "!=". In addition, awk provides the "~" and "!~" operators, which mean "matches" and "does not match". They're used by specifying a variable on the left side of the operator, and a regular expression on the right side. Here's an example that will print only the third field on the line if the fifth field on the same line contains the character sequence root:
If you're using new-school GPT partitions for UEFI, you'll want to create a vfat filesystem on /dev/sda1, because this is what UEFI is able to read:


<pre>$5 ~ /root/ { print $3 }</pre>
<console>
# ##i##mkfs.vfat -F 32 /dev/sda1
</console>


=== Conditional statements ===
Now, let's create a swap partition. This partition will be used as disk-based virtual memory for your Funtoo Linux system.
Awk also offers very nice C-like if statements. If you'd like, you could rewrite the previous script using an if statement:
<pre>
{
    if ( $5 ~ /root/ ) {
        print $3
    }
}
</pre>
Both scripts function identically. In the first example, the boolean expression is placed outside the block, while in the second example, the block is executed for every input line, and we selectively perform the print command by using an if statement. Both methods are available, and you can choose the one that best meshes with the other parts of your script.


Here's a more complicated example of an awk if statement. As you can see, even with complex, nested conditionals, if statements look identical to their C counterparts:
You will not create a filesystem on your swap partition, since it is not used to store files. But it is necessary to initialize it using the <code>mkswap</code> command. Then we'll run the <code>swapon</code> command to make your newly-initialized swap space immediately active within the live CD environment, in case it is needed during the rest of the install process:
<pre>
{
    if ( $1 == "foo" ) {
        if ( $2 == "foo" ) {
            print "uno"
        } else {
            print "one"
        }
    } else if ($1 == "bar" ) {
        print "two"
    } else {
        print "three"
    }
}
</pre>
Using if statements, we can also transform this code:
<pre>
! /matchme/ { print $1 $3 $4 }
</pre>
to this:
<pre>
{
    if ( $0 !~ /matchme/ ) {
        print $1 $3 $4
    }
}
</pre>
Both scripts will output only those lines that don't contain a matchme character sequence. Again, you can choose the method that works best for your code. They both do the same thing.


Awk also allows the use of boolean operators "||" (for "logical or") and "&&"(for "logical and") to allow the creation of more complex boolean expressions:
<console>
<pre>
# ##i##mkswap /dev/sda2
( $1 == "foo" ) && ( $2 == "bar" ) { print }
# ##i##swapon /dev/sda2
</pre>
</console>
This example will print only those lines where field one equals foo and field two equals bar.


=== Numeric variables! ===
Now, we need to create a root filesystem. This is where Funtoo Linux will live. We generally recommend ext4 or XFS root filesystems. If you're not sure, choose ext4. Here's how to create a root ext4 filesystem:
So far, we've either printed strings, the entire line, or specific fields. However, awk also allows us to perform both integer and floating point math. Using mathematical expressions, it's very easy to write a script that counts the number of blank lines in a file. Here's one that does just that:
<pre>
BEGIN { x=0 }
/^$/  { x=x+1 }
END  { print "I found " x " blank lines. :)" }
</pre>
In the BEGIN block, we initialize our integer variable x to zero. Then, each time awk encounters a blank line, awk will execute the x=x+1 statement, incrementing x. After all the lines have been processed, the END block will execute, and awk will print out a final summary, specifying the number of blank lines it found.


=== Stringy variables ===
<console>
One of the neat things about awk variables is that they are "simple and stringy." I consider awk variables "stringy" because all awk variables are stored internally as strings. At the same time, awk variables are "simple" because you can perform mathematical operations on a variable, and as long as it contains a valid numeric string, awk automatically takes care of the string-to-number conversion steps. To see what I mean, check out this example:
# ##i##mkfs.ext4 /dev/sda3
<pre>
</console>
x="1.01"
# We just set x to contain the *string* "1.01"
x=x+1
# We just added one to a *string*
print x
# Incidentally, these are comments :)
</pre>
Awk will output:
<pre>
2.01
</pre>
Interesting! Although we assigned the string value 1.01 to the variable x, we were still able to add one to it. We wouldn't be able to do this in bash or python. First of all, bash doesn't support floating point arithmetic. And, while bash has "stringy" variables, they aren't "simple"; to perform any mathematical operations, bash requires that we enclose our math in an ugly $( ) construct. If we were using python, we would have to explicitly convert our 1.01 string to a floating point value before performing any arithmetic on it. While this isn't difficult, it's still an additional step. With awk, it's all automatic, and that makes our code nice and clean. If we wanted to square and add one to the first field in each input line, we would use this script:
<pre>
{ print ($1^2)+1 }
</pre>
If you do a little experimenting, you'll find that if a particular variable doesn't contain a valid number, awk will treat that variable as a numerical zero when it evaluates your mathematical expression.


=== Lots of operators ===
...and here's how to create an XFS root filesystem, if you choose to use XFS:
Another nice thing about awk is its full complement of mathematical operators. In addition to standard addition, subtraction, multiplication, and division, awk allows us to use the previously demonstrated exponent operator "^", the modulo (remainder) operator "%", and a bunch of other handy assignment operators borrowed from C.


These include pre- and post-increment/decrement ( i++, --foo ), add/sub/mult/div assign operators ( a+=3, b*=2, c/=2.2, d-=6.2 ). But that's not all -- we also get handy modulo/exponent assign ops as well ( a^=2, b%=4 ).
<console>
# ##i##mkfs.xfs /dev/sda3
</console>


=== Field separators ===
Your filesystems (and swap) have all now been initialized, so that that can be mounted (attached to your existing directory heirarchy) and used to store files. We are ready to begin installing Funtoo Linux on these brand-new filesystems.
Awk has its own complement of special variables. Some of them allow you to fine-tune how awk functions, while others can be read to glean valuable information about the input. We've already touched on one of these special variables, FS. As mentioned earlier, this variable allows you to set the character sequence that awk expects to find between fields. When we were using /etc/passwd as input, FS was set to ":". While this did the trick, FS allows us even more flexibility.


The FS value is not limited to a single character; it can also be set to a regular expression, specifying a character pattern of any length. If you're processing fields separated by one or more tabs, you'll want to set FS like so:
{{fancywarning|1=
<pre>
When deploying an OpenVZ host, please use ext4 exclusively. The Parallels development team tests extensively with ext4, and modern versions of <code>openvz-rhel6-stable</code> are '''not''' compatible with XFS, and you may experience kernel bugs.
FS="\t+"
}}
</pre>
Above, we use the special "+" regular expression character, which means "one or more of the previous character".


If your fields are separated by whitespace (one or more spaces or tabs), you may be tempted to set FS to the following regular expression:
==== Mounting filesystems ====
<pre>
FS="[[:space:]]+"
</pre>
While this assignment will do the trick, it's not necessary. Why? Because by default, FS is set to a single space character, which awk interprets to mean "one or more spaces or tabs." In this particular example, the default FS setting was exactly what you wanted in the first place!


Complex regular expressions are no problem. Even if your records are separated by the word "foo," followed by three digits, the following regular expression will allow your data to be parsed properly:
Mount the newly-created filesystems as follows, creating <code>/mnt/funtoo</code> as the installation mount point:
<pre>
FS="foo[0-9][0-9][0-9]"
</pre>


=== Number of fields ===
<console>
The next two variables we're going to cover are not normally intended to be written to, but are normally read and used to gain useful information about the input. The first is the NF variable, also called the "number of fields" variable. Awk will automatically set this variable to the number of fields in the current record. You can use the NF variable to display only certain input lines:
# ##i##mkdir /mnt/funtoo
<pre>
# ##i##mount /dev/sda3 /mnt/funtoo
NF == 3 { print "this particular record has three fields: " $0 }
# ##i##mkdir /mnt/funtoo/boot
</pre>
# ##i##mount /dev/sda1 /mnt/funtoo/boot
Of course, you can also use the NF variable in conditional statements, as follows:
</console>
<pre>
{
    if ( NF > 2 ) {
        print $1 " " $2 ":" $3
    }
}
</pre>


=== Record number ===
Optionally, if you have a separate filesystem for <code>/home</code> or anything else:
The record number (NR) is another handy variable. It will always contain the number of the current record (awk counts the first record as record number 1). Up until now, we've been dealing with input files that contain one record per line. For these situations, NR will also tell you the current line number. However, when we start to process multi-line records later in the series, this will no longer be the case, so be careful! NR can be used like the NF variable to print only certain lines of the input:
<pre>
(NR < 10 ) || (NR > 100) { print "We are on record number 1-9 or 101+" }
</pre>
<pre>
{
    #skip header
    if ( NR > 10 ) {
        print "ok, now for the real information!"
    }
}
</pre>
Awk provides additional variables that can be used for a variety of purposes. We'll cover more of these variables in later articles.


We've come to the end of our initial exploration of awk. As the series continues, I'll demonstrate more advanced awk functionality, and we'll end the series with a real-world awk application.
<console>
# ##i##mkdir /mnt/funtoo/home
# ##i##mount /dev/sda4 /mnt/funtoo/home
</console>


== Resources ==
If you have <code>/tmp</code> or <code>/var/tmp</code> on a separate filesystem, be sure to change the permissions of the mount point to be globally-writeable after mounting, as follows:


* Read Daniel's other awk articles on Funtoo: Awk By Example, [[Awk by example, Part2 |Part 2]] and [[Awk by example, Part3 |Part 3]].
<console>
* If you'd like a good old-fashioned book, [http://www.oreilly.com/catalog/sed2/ O'Reilly's sed & awk, 2nd Edition] is a wonderful choice.
# ##i##chmod 1777 /mnt/funtoo/tmp
* Be sure to check out the [http://www.faqs.org/faqs/computer-lang/awk/faq/ comp.lang.awk FAQ]. It also contains lots of additional awk links.
</console>
* Patrick Hartigan's [http://sparky.rice.edu/~hartigan/awk.html awk tutorial] is packed with handy awk scripts.
* [http://www.tasoft.com/tawk.html Thompson's TAWK Compiler] compiles awk scripts into fast binary executables. Versions are available for Windows, OS/2, DOS, and UNIX.
* [http://www.gnu.org/software/gawk/manual/gawk.html The GNU Awk User's Guide] is available for online reference.
* [http://www.folkstalk.com/2011/12/good-examples-of-awk-command-in-unix.html Awk Command] daily useful examples.
[[Category:Linux Core Concepts]]
[[Category:Articles]]
{{ArticleFooter}}

Revision as of 13:31, January 5, 2015


   Note

This is a template that is used as part of the Installation instructions which covers: процесс разбиения диска и создания файловых систем. Templates are being used to allow multiple variant install guides that use most of the same re-usable parts.


Подготовка жесткого диска

В этой части мы научимся различным способам установки Funtoo Linux -- и загрузки с -- жесткий диск.

Введение

В прежние времена существовал лишь один способ загрузить PC-совместимый компьютер. Все наши дектопы и сервера имели стандартный PC BIOS, все наши харды использовали MBR и были разбиты используя схему разбивки MBR. Вот как это все было и нам это нравилось!

Затем появились EFI и UEFI, встроенные программы нового образца наряду со схемой разбивки GPT, поддерживающая диски размером более 2.2TБ. Неожиданно, нам стали доступны различные способы установки и загрузки Линукс систем . То, что было единым методом, стало чем-то более сложным.

Let's take a moment to review the options available to you for configuring a hard drive to boot Funtoo Linux. This Install Guide uses, and recommends, the old-school method of BIOS booting and using an MBR. It works and (except for rare cases) is universally supported. There's nothing wrong with it. If your system disk is 2TB or smaller in size, it won't prevent you from using all of your disk's capacity, either.

But, there are some situations where the old-school method isn't optimal. If you have a system disk >2TB in size, then MBR partitions won't allow you to access all your storage. So that's one reason. Another reason is that there are some so-called "PC" systems out there that don't support BIOS booting anymore, and force you to use UEFI to boot. So, out of compassion for people who fall into this predicament, this Install Guide documents UEFI booting too.

Our recommendation is still to go old-school unless you have reason not to. The boot loader we will be using to load the Linux kernel in this guide is called GRUB, so we call this method the BIOS + GRUB (MBR) method. It's the traditional method of setting up a PC-compatible system to boot Linux.

If you need to use UEFI to boot, we recommend not using the MBR at all for booting, as some systems support this, but others don't. Instead, we recommend using UEFI to boot GRUB, which in turn will load Linux. We refer to this method as the UEFI + GRUB (GPT) method.

And yes, there are even more methods, some of which are documented on the Boot Methods page. We used to recommend a BIOS + GRUB (GPT) method but it is not consistently supported across a wide variety of hardware.

The big question is -- which boot method should you use? Here's how to tell.

Principle 1 - Old School
If you can reliably boot System Rescue CD and it shows you an initial light blue menu, you are booting the CD using the BIOS, and it's likely that you can thus boot Funtoo Linux using the BIOS. So, go old-school and use BIOS booting, unless you have some reason to use UEFI, such as having a >2.2TB system disk. In that case, see Principle 2, as your system may also support UEFI booting.
Principle 2 - New School
If you can reliably boot System Rescue CD and it shows you an initial black and white menu -- congratulations, your system is configured to support UEFI booting. This means that you are ready to install Funtoo Linux to boot via UEFI. Your system may still support BIOS booting, but just be trying UEFI first. You can poke around in your BIOS boot configuration and play with this.
What's the Big Difference between Old School and New School?
Here's the deal. If you go with old-school MBR partitions, your /boot partition will be an ext2 filesystem, and you'll use fdisk to create your MBR partitions. If you go with new-school GPT partitions and UEFI booting, your /boot partition will be a vfat filesystem, because this is what UEFI is able to read, and you will use gdisk to create your GPT partitions. And you'll install GRUB a bit differently. That's about all it comes down to, in case you were curious.
Also Note
To install Funtoo Linux to boot via the New School UEFI method, you must boot System Rescue CD using UEFI -- and see an initial black and white screen. Otherwise, UEFI will not be active and you will not be able to set it up!
   Note

Some motherboards may appear to support UEFI, but don't. Do your research. For example, the Award BIOS in my Gigabyte GA-990FXA-UD7 rev 1.1 has an option to enable UEFI boot for CD/DVD. This is not sufficient for enabling UEFI boot for hard drives and installing Funtoo Linux. UEFI must be supported for both removable media (so you can boot System Rescue CD using UEFI) as well as fixed media (so you can boot your new Funtoo Linux installation.) It turns out that later revisions of this board (rev 3.0) have a new BIOS that fully supports UEFI boot. This may point to a third principle -- know thy hardware.

Old-School (BIOS/MBR) Method

   Note

Use this method if you are booting using your BIOS, and if your System Rescue CD initial boot menu was light blue. If you're going to use the new-school method, click here to jump down to UEFI/GPT.

Preparation

First, it's a good idea to make sure that you've found the correct hard disk to partition. Try this command and verify that /dev/sda is the disk that you want to partition: 

root # fdisk -l /dev/sda

Disk /dev/sda: 640.1 GB, 640135028736 bytes, 1250263728 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: gpt


root #         Start          End    Size  Type            Name
 1         2048   1250263694  596.2G  Linux filesyste Linux filesystem

Now, it's recommended that you erase any existing MBR or GPT partition tables on the disk, which could confuse the system's BIOS at boot time. We do this using sgdisk:

   Warning

This will make any existing partitions inaccessible! You are strongly cautioned and advised to backup any critical data before proceeding. 

root # sgdisk --zap-all /dev/sda

Creating new GPT entries.
GPT data structures destroyed! You may now partition the disk using fdisk or
other utilities.

This output is also nothing to worry about, as the command still succeded: 

***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory. 
***************************************************************
Partitioning

Now we will use fdisk to create the MBR partition table and partitions: 

root # fdisk /dev/sda

Within fdisk, follow these steps:

Empty the partition table: 

Command (m for help): o ↵

Create Partition 1 (boot): 

Command (m for help): n ↵
Partition type (default p): ↵
Partition number (1-4, default 1): ↵
First sector: ↵
Last sector: +128M ↵

Create Partition 2 (swap): 

Command (m for help): n ↵
Partition type (default p): ↵
Partition number (2-4, default 2): ↵
First sector: ↵
Last sector: +2G ↵
Command (m for help): t ↵ 
Partition number (1,2, default 2):  ↵
Hex code (type L to list all codes): 82 ↵

Create the root partition: 

Command (m for help): n ↵
Partition type (default p): ↵
Partition number (3,4, default 3): ↵
First sector: ↵
Last sector: ↵

Verify the partition table: 

Command (m for help): p

Disk /dev/sda: 298.1 GiB, 320072933376 bytes, 625142448 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x82abc9a6

Device    Boot     Start       End    Blocks  Id System
/dev/sda1           2048    264191    131072  83 Linux
/dev/sda2         264192   4458495   2097152  82 Linux swap / Solaris
/dev/sda3        4458496 625142447 310341976  83 Linux

Write the parition table to disk: 

Command (m for help): w

Your new MBR partition table will now be written to your system disk.

   Note

You're done with partitioning! Now, jump over to Creating filesystems.

New-School (UEFI/GPT) Method

   Note

Use this method if you are booting using UEFI, and if your System Rescue CD initial boot menu was black and white. If it was light blue, this method will not work.

The gdisk commands to create a GPT partition table are as follows. Adapt sizes as necessary, although these defaults will work for most users. Start gdisk: 

root # gdisk

Within gdisk, follow these steps:

Create a new empty partition table (This will erase all data on the disk when saved): 

Command: o ↵
This option deletes all partitions and creates a new protective MBR.
Proceed? (Y/N): y ↵

Create Partition 1 (boot): 

Command: n ↵
Partition Number: 1 ↵
First sector: ↵
Last sector: +500M ↵
Hex Code: ↵

Create Partition 2 (swap): 

Command: n ↵
Partition Number: 2 ↵
First sector: ↵
Last sector: +4G ↵
Hex Code: 8200 ↵

Create Partition 3 (root): 

Command: n ↵
Partition Number: 3 ↵
First sector: ↵
Last sector: ↵ (for rest of disk)
Hex Code: ↵

Along the way, you can type "p" and hit Enter to view your current partition table. If you make a mistake, you can type "d" to delete an existing partition that you created. When you are satisfied with your partition setup, type "w" to write your configuration to disk:

Write Partition Table To Disk: 

Command: w ↵
Do you want to proceed? (Y/N): Y ↵

The partition table will now be written to disk and gdisk will close.

Now, your GPT/GUID partitions have been created, and will show up as the following block devices under Linux:

  • /dev/sda1, which will be used to hold the /boot filesystem,
  • /dev/sda2, which will be used for swap space, and
  • /dev/sda3, which will hold your root filesystem.

Creating filesystems

   Note

This section covers both BIOS and UEFI installs. Don't skip it!

Before your newly-created partitions can be used, the block devices need to be initialized with filesystem metadata. This process is known as creating a filesystem on the block devices. After filesystems are created on the block devices, they can be mounted and used to store files.

Let's keep this simple. Are you using old-school MBR partitions? If so, let's create an ext2 filesystem on /dev/sda1: 

root # mkfs.ext2 /dev/sda1

If you're using new-school GPT partitions for UEFI, you'll want to create a vfat filesystem on /dev/sda1, because this is what UEFI is able to read: 

root # mkfs.vfat -F 32 /dev/sda1

Now, let's create a swap partition. This partition will be used as disk-based virtual memory for your Funtoo Linux system.

You will not create a filesystem on your swap partition, since it is not used to store files. But it is necessary to initialize it using the mkswap command. Then we'll run the swapon command to make your newly-initialized swap space immediately active within the live CD environment, in case it is needed during the rest of the install process: 

root # mkswap /dev/sda2
root # swapon /dev/sda2

Now, we need to create a root filesystem. This is where Funtoo Linux will live. We generally recommend ext4 or XFS root filesystems. If you're not sure, choose ext4. Here's how to create a root ext4 filesystem: 

root # mkfs.ext4 /dev/sda3

...and here's how to create an XFS root filesystem, if you choose to use XFS: 

root # mkfs.xfs /dev/sda3

Your filesystems (and swap) have all now been initialized, so that that can be mounted (attached to your existing directory heirarchy) and used to store files. We are ready to begin installing Funtoo Linux on these brand-new filesystems.

   Warning

When deploying an OpenVZ host, please use ext4 exclusively. The Parallels development team tests extensively with ext4, and modern versions of openvz-rhel6-stable are not compatible with XFS, and you may experience kernel bugs.

Mounting filesystems

Mount the newly-created filesystems as follows, creating /mnt/funtoo as the installation mount point: 

root # mkdir /mnt/funtoo
root # mount /dev/sda3 /mnt/funtoo
root # mkdir /mnt/funtoo/boot
root # mount /dev/sda1 /mnt/funtoo/boot

Optionally, if you have a separate filesystem for /home or anything else: 

root # mkdir /mnt/funtoo/home
root # mount /dev/sda4 /mnt/funtoo/home

If you have /tmp or /var/tmp on a separate filesystem, be sure to change the permissions of the mount point to be globally-writeable after mounting, as follows: 

root # chmod 1777 /mnt/funtoo/tmp
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