Final Lab 11 - Revision history

KreidKolo: /* Exploring /dev */

2021-01-28T03:06:36Z

Exploring /dev

← Older revision		Revision as of 03:06, 28 January 2021
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	== Exploring /dev ==		== Exploring /dev ==
	<ol>		<ol>
	<li> Change directories to ''/dev'' and list the "files". </li>		<li> Change directories to [https://tldp.org/LDP/sag/html/dev-fs.html ''/dev''] and list the "files". </li>
	:Notice there are A LOT, but don't worry, there is organization in the mess. Each "file", like in ''/proc'', is actually a device or interface on the machine so ''/dev'' is actually another pseudo-filesystem. Here is a list of the most common interfaces you will see:		:Notice there are A LOT, but don't worry, there is organization in the mess. Each "file", like in ''/proc'', is actually a device or interface on the machine so ''/dev'' is actually another pseudo-filesystem. Here is a list of the most common interfaces you will see:
	* ''/dev/sd*'' = SATA Hard Drives		* ''/dev/sd*'' = SATA Hard Drives

KreidKolo: /* Exploring /proc */

2021-01-28T03:06:07Z

Exploring /proc

← Older revision		Revision as of 03:06, 28 January 2021
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	== Exploring /proc ==		== Exploring /proc ==
	<ol>		<ol>
	<li> Enter the ''/proc'' directory on your VM. </li>		<li> Enter the [https://www.linux.com/news/discover-possibilities-proc-directory/ ''/proc''] directory on your VM. </li>
	: ''/proc'' is a very special folder is its a virtual filesystem. Its sometimes referred to as a process information pseudo-filesystem. The reason for calling it a pseudo-file system is that all of the "files" in ''/proc'' are not really files at all, but kernel runtime configuration and system information.		: ''/proc'' is a very special folder is its a virtual filesystem. Its sometimes referred to as a process information pseudo-filesystem. The reason for calling it a pseudo-file system is that all of the "files" in ''/proc'' are not really files at all, but kernel runtime configuration and system information.
	<li> Use '''cat cpuinfo''' to view the contents of the ''/proc/cpuinfo'' "file". </li>		<li> Use '''cat cpuinfo''' to view the contents of the ''/proc/cpuinfo'' "file". </li>

NateHaleen: /* Adding a 2nd disk */

2021-01-27T18:34:11Z

Adding a 2nd disk

← Older revision		Revision as of 18:34, 27 January 2021
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	<li> To start, run the following as root:		<li> To start, run the following as root:
	<pre>cfdisk /dev/sdb</pre> </li>		<pre>cfdisk /dev/sdb</pre> </li>
	:''cfdisk'' is a graphical version of ''fdisk'', which is a tool used to setup disk partitioning. Note that ''fdisk'' or any other partitioning software only sets up the MBR, and does not actually format the drive even though you can set a partition type identifier such as '''fat32''', '''Linux''', etc. Also notice how we tell ''cfdisk'' what drive we want to edit the partition on by appending the drive device "file" to the end of the command.		:''cfdisk'' is a graphical version of ''fdisk'', which is a tool used to setup disk partitioning. Note that ''fdisk'' or any other partitioning software only sets up the MBR, and does not actually format the drive even though you can set a partition type identifier such as ''fat32'', ''Linux'', etc. Also notice how we tell ''cfdisk'' what drive we want to edit the partition on by appending the drive device "file" to the end of the command.
	: [[File:Test-screenshot.png\|250px]]		: [[File:Test-screenshot.png\|250px]]
	: Because our new drives contain no existing partitions we are asked what type of partition table to create.		: Because our new drives contain no existing partitions we are asked what type of partition table to create.

NateHaleen: /* Exploring /dev */

2021-01-27T18:33:11Z

Exploring /dev

← Older revision		Revision as of 18:33, 27 January 2021
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	<li> Change directories to ''/dev'' and list the "files". </li>		<li> Change directories to ''/dev'' and list the "files". </li>
	:Notice there are A LOT, but don't worry, there is organization in the mess. Each "file", like in ''/proc'', is actually a device or interface on the machine so ''/dev'' is actually another pseudo-filesystem. Here is a list of the most common interfaces you will see:		:Notice there are A LOT, but don't worry, there is organization in the mess. Each "file", like in ''/proc'', is actually a device or interface on the machine so ''/dev'' is actually another pseudo-filesystem. Here is a list of the most common interfaces you will see:
	* '''/dev/sd*''' = SATA Hard Drives		* ''/dev/sd*'' = SATA Hard Drives
	* '''/dev/hd*''' = IDE Hard Drives		* ''/dev/hd*'' = IDE Hard Drives
	* '''/dev/vd*''' = VirtIO (Virtualized) Hard Drives		* ''/dev/vd*'' = VirtIO (Virtualized) Hard Drives
	* '''/dev/ttyS*''' = Serial Interfaces on your PC.		* ''/dev/ttyS*'' = Serial Interfaces on your PC.
	* '''/dev/tty*''' = Virtual Consoles, similar to the one you are using to enter commands. Mostly used by background programs or services.		* ''/dev/tty*'' = Virtual Consoles, similar to the one you are using to enter commands. Mostly used by background programs or services.
	: There are also some commands you should learn that will help you with detecting, and looking up devices:		: There are also some commands you should learn that will help you with detecting, and looking up devices:
	: '''lsusb''' = List USB Devices (Bus, Device, ID, and advertised vendor)		: '''lsusb''' = List USB Devices (Bus, Device, ID, and advertised vendor)

NateHaleen: /* Exploring /proc */

2021-01-27T18:32:43Z

Exploring /proc

← Older revision		Revision as of 18:32, 27 January 2021
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	: Notice how the output tells your information about the CPU that is running the VM. This isn't actually a file at all you are essentially asking the kernel to provide information about the CPU it's running on which it gathers in realtime. ''/proc'' is used not only to get hardware and kernel information, but it can also be used to tweak kernel settings while the system is running in a way similar to some Windows Registry edits. Look back on [[Franske ITC-2480 Lab 10#Enable Routing\|Lab 10]] and notice how we echoed a "1" to a "file" in ''/proc'' to enable packet forwarding without rebooting the system.		: Notice how the output tells your information about the CPU that is running the VM. This isn't actually a file at all you are essentially asking the kernel to provide information about the CPU it's running on which it gathers in realtime. ''/proc'' is used not only to get hardware and kernel information, but it can also be used to tweak kernel settings while the system is running in a way similar to some Windows Registry edits. Look back on [[Franske ITC-2480 Lab 10#Enable Routing\|Lab 10]] and notice how we echoed a "1" to a "file" in ''/proc'' to enable packet forwarding without rebooting the system.
	: There are a few files in ''/proc'' you should get to know:		: There are a few files in ''/proc'' you should get to know:
	* '''/proc/cpuinfo''' = Shows you the CPU info for your machine.		* ''/proc/cpuinfo'' = Shows you the CPU info for your machine.
	* '''/proc/modules''' = Shows you the currently enabled kernel modules that are active on your kernel.		* ''/proc/modules'' = Shows you the currently enabled kernel modules that are active on your kernel.
	* '''/proc/cmdline''' = Shows you the boot arguments used to boot your kernel.		* ''/proc/cmdline'' = Shows you the boot arguments used to boot your kernel.
	* '''/proc/version''' = Shows you your kernel version.		* ''/proc/version'' = Shows you your kernel version.
	: It is important to note that some of these files have commands tied to them that can give you similar information but often formatted in a different way, for example.		: It is important to note that some of these files have commands tied to them that can give you similar information but often formatted in a different way, for example.
	: '''lsmod''' = '''/proc/modules'''		: '''lsmod''' = ''/proc/modules''
	: '''mount''' = '''/proc/mounts'''		: '''mount''' = ''/proc/mounts''
	: '''uname -a''' = '''/proc/version'''		: '''uname -a''' = ''/proc/version''
	: Normally it is best to use the command version to lookup the information as it is normally formatted to be easier to read and understand.		: Normally it is best to use the command version to lookup the information as it is normally formatted to be easier to read and understand.
	<li> Explore all of these files and commands and find the differences between the command line and file output versions as well as what types of information are available. </li>		<li> Explore all of these files and commands and find the differences between the command line and file output versions as well as what types of information are available. </li>

NateHaleen: /* Exploring /proc */

2021-01-27T18:32:03Z

Exploring /proc

← Older revision		Revision as of 18:32, 27 January 2021
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	* '''/proc/version''' = Shows you your kernel version.		* '''/proc/version''' = Shows you your kernel version.
	: It is important to note that some of these files have commands tied to them that can give you similar information but often formatted in a different way, for example.		: It is important to note that some of these files have commands tied to them that can give you similar information but often formatted in a different way, for example.
	*: '''lsmod''' = '''/proc/modules'''		: '''lsmod''' = '''/proc/modules'''
	*: '''mount''' = '''/proc/mounts'''		: '''mount''' = '''/proc/mounts'''
	*: '''uname -a''' = '''/proc/version'''		: '''uname -a''' = '''/proc/version'''
	: Normally it is best to use the command version to lookup the information as it is normally formatted to be easier to read and understand.		: Normally it is best to use the command version to lookup the information as it is normally formatted to be easier to read and understand.
	<li> Explore all of these files and commands and find the differences between the command line and file output versions as well as what types of information are available. </li>		<li> Explore all of these files and commands and find the differences between the command line and file output versions as well as what types of information are available. </li>

NateHaleen: /* Exploring /proc */

2021-01-27T18:31:38Z

Exploring /proc

← Older revision		Revision as of 18:31, 27 January 2021
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	* '''/proc/version''' = Shows you your kernel version.		* '''/proc/version''' = Shows you your kernel version.
	: It is important to note that some of these files have commands tied to them that can give you similar information but often formatted in a different way, for example.		: It is important to note that some of these files have commands tied to them that can give you similar information but often formatted in a different way, for example.
	* '''~~/proc/modules~~''' = '''~~lsmod~~'''		*: '''lsmod''' = '''/proc/modules'''
	* '''~~/proc/mounts~~''' = '''~~mount~~'''		*: '''mount''' = '''/proc/mounts'''
	* '''~~/proc/version~~''' = '''~~uname -a~~'''		*: '''uname -a''' = '''/proc/version'''
	: Normally it is best to use the command version to lookup the information as it is normally formatted to be easier to read and understand.		: Normally it is best to use the command version to lookup the information as it is normally formatted to be easier to read and understand.
	<li> Explore all of these files and commands and find the differences between the command line and file output versions as well as what types of information are available. </li>		<li> Explore all of these files and commands and find the differences between the command line and file output versions as well as what types of information are available. </li>

MikeTieden at 00:29, 27 January 2021

2021-01-27T00:29:45Z

← Older revision		Revision as of 00:29, 27 January 2021
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	<pre>cp -r /var/log ./</pre> </li>		<pre>cp -r /var/log ./</pre> </li>
	<li> '''cd''' into the ''log'' folder, and run the following:		<li> '''cd''' into the ''log'' folder, and run the following:
	<pre> du -h~~'''~~</pre> </li>		<pre> du -h</pre> </li>
	: '''du''' is a command that allows you to view file usage in a tree format. Just like with '''df''' the ''-h'' flag tells '''du''' to output the usage in a "human readable" format, while the ''-a'' flag tells it to show you the results for all files, and not just for folders.		: '''du''' is a command that allows you to view file usage in a tree format. Just like with '''df''' the ''-h'' flag tells '''du''' to output the usage in a "human readable" format, while the ''-a'' flag tells it to show you the results for all files, and not just for folders.
	<li> Read the '''man du''' page and play around with using the '''du''' command across the file system. </li>		<li> Read the '''man du''' page and play around with using the '''du''' command across the file system. </li>

MikeTieden at 00:28, 27 January 2021

2021-01-27T00:28:57Z

← Older revision		Revision as of 00:28, 27 January 2021
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	: ''If, on the bottom of the screen, you see "The partition table has been altered", you have successfully written the MBR to the drive.''		: ''If, on the bottom of the screen, you see "The partition table has been altered", you have successfully written the MBR to the drive.''
	<li> Navigate to ''Quit'' to exit the program.</li>		<li> Navigate to ''Quit'' to exit the program.</li>
	<li> From the command line run ~~'''~~ls -al /dev/sd*~~'''~~. </li>		<li> From the command line run the following:
			<pre>ls -al /dev/sd*</pre>. </li>
	: Notice how you can now see both of the new partitions, ''sdb1'' and ''sdb2'' in the listing. This means the partition device "files" have been created and you are ready to format the partitions with a filesystem.		: Notice how you can now see both of the new partitions, ''sdb1'' and ''sdb2'' in the listing. This means the partition device "files" have been created and you are ready to format the partitions with a filesystem.
	: The first partition will be formatted as ''ext4'', and the second partition will be formatted as ''btrfs''. Both filesystems (as well as many others) are commonly used on Linux systems. For more information on the differences and similarities between ''btrfs'' and ''ext4'', refer to your book or Google.		: The first partition will be formatted as ''ext4'', and the second partition will be formatted as ''btrfs''. Both filesystems (as well as many others) are commonly used on Linux systems. For more information on the differences and similarities between ''btrfs'' and ''ext4'', refer to your book or Google.
	: To create the ''ext4'' partition, we will use the '''mkfs.ext4''' command.		: To create the ''ext4'' partition, we will use the '''mkfs.ext4''' command.
	<li> As root, run the command ~~'''~~mkfs.ext4 /dev/sdb1~~'''~~. </li>		<li> As root, run the follwing command
			<pre>mkfs.ext4 /dev/sdb1</pre>. </li>
	: This will partition the drive as ''ext4'' with no label. If you would like to label the partition, look into the options of ''mkfs.ext4'' using '''man mkfs.ext4'''.		: This will partition the drive as ''ext4'' with no label. If you would like to label the partition, look into the options of ''mkfs.ext4'' using '''man mkfs.ext4'''.
	: Before formatting the other partition as ''btrfs'' we need to install some tools.		: Before formatting the other partition as ''btrfs'' we need to install some tools.
	<li> The required tools are part of the ''btrfs-tools'' software package so install that package at this time.</li>		<li> The required tools are part of the ''btrfs-tools'' software package so install that package at this time.</li>
	* ''Note: if you have issues with installing packages, check your firewall rules you created in a previous lab and ensure your Internet access is working properly from the VM.''		* ''Note: if you have issues with installing packages, check your firewall rules you created in a previous lab and ensure your Internet access is working properly from the VM.''
	<li> To format the second partition as a ''btrfs'' filesystem partition we will run ~~'''~~mkfs.btrfs /dev/sdb2~~'''~~. </li>		<li> To format the second partition as a ''btrfs'' filesystem partition we will run the following:
			<pre>mkfs.btrfs /dev/sdb2</pre>. </li>
	: Just like before, we need to tell the ''mkfs.btrfs'' package what partition to format by including that on the command line.		: Just like before, we need to tell the ''mkfs.btrfs'' package what partition to format by including that on the command line.
	: There are many other options that can be set for specific filesystems during the formatting process. For example, many newer large drives use 4096 byte "Advanced Format" sectors instead of the traditional 512 byte hard drive sectors. Using these disks most efficiently requires adjusting the sector size during the format process to match the physical sector size on the disk. Other features and filesystems include the ability to take snapshots of the drive for backups. The full details of all the options, settings, and filesystems available in Linux is beyond the scope of this course. Suffice it to say that Linux systems with a need for high speed I/O from disks or other specialized features are finely tuned.		: There are many other options that can be set for specific filesystems during the formatting process. For example, many newer large drives use 4096 byte "Advanced Format" sectors instead of the traditional 512 byte hard drive sectors. Using these disks most efficiently requires adjusting the sector size during the format process to match the physical sector size on the disk. Other features and filesystems include the ability to take snapshots of the drive for backups. The full details of all the options, settings, and filesystems available in Linux is beyond the scope of this course. Suffice it to say that Linux systems with a need for high speed I/O from disks or other specialized features are finely tuned.
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	: Because we have not yet mounted ''/dev/sdb1'' this file will be stored on our existing partition (''/dev/sda1'').		: Because we have not yet mounted ''/dev/sdb1'' this file will be stored on our existing partition (''/dev/sda1'').
	<li> Go back to the ''/mnt'' parent directory. </li>		<li> Go back to the ''/mnt'' parent directory. </li>
	<li> Run the ~~'''~~mount /dev/sdb1 /mnt/part1~~''' command as root.~~ </li>		<li> Run the following as root:
	~~: [[File:Test-screenshot.png\|250px]]~~		<pre>mount /dev/sdb1 /mnt/part1</pre> </li>
	: This command will mount, or attach, ''/dev/sdb1'' to the filesystem location ''/mnt/part1'' and everything stored in that "directory" from this point on will actually be saved onto the first partition of the second SATA drive.		: This command will mount, or attach, ''/dev/sdb1'' to the filesystem location ''/mnt/part1'' and everything stored in that "directory" from this point on will actually be saved onto the first partition of the second SATA drive.
	<li> Go back into the ''part1'' directory and try listing the files. </li>		<li> Go back into the ''part1'' directory and try listing the files. </li>
			: [[File:Test-screenshot.png\|250px]]
	: Notice how the ''unmounted ''file you made appears to no longer exist. This is because the ''part1'' "directory is now being used as the mount point for the first partition on ''sdb'' and we haven't yet saved any files onto ''sdb1''.		: Notice how the ''unmounted ''file you made appears to no longer exist. This is because the ''part1'' "directory is now being used as the mount point for the first partition on ''sdb'' and we haven't yet saved any files onto ''sdb1''.
	<li> You can see a list of all storage devices currently mounted on the system by simply running the command '''mount''' without any options. Try doing this and verify that the newly mounted partition is showing in the list.</li>		<li> You can see a list of all storage devices currently mounted on the system by simply running the command '''mount''' without any options. Try doing this and verify that the newly mounted partition is showing in the list.</li>
	<li> Change back to the ''/mnt'' directory and unmount the partition by running the command ~~'''~~umount /mnt/part1~~'''.~~</li>		<li> Change back to the ''/mnt'' directory and unmount the partition by running the following command
			<pre>umount /mnt/part1</pre> </li>
	<li> Again list the contents of the ''part1'' directory. </li>		<li> Again list the contents of the ''part1'' directory. </li>
	: Notice how the ''unmounted'' file is back. The file didn't every really go away but it was not accessible while the other partition was mounted on the ''part1'' directory. When a drive is mounted on a directory, it overlays on top of any files in the directory, but it does not delete or touch the files on the original disk.		: Notice how the ''unmounted'' file is back. The file didn't every really go away but it was not accessible while the other partition was mounted on the ''part1'' directory. When a drive is mounted on a directory, it overlays on top of any files in the directory, but it does not delete or touch the files on the original disk.
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	/dev/sdb2 /mnt/btrfs btrfs defaults 0 0</pre>		/dev/sdb2 /mnt/btrfs btrfs defaults 0 0</pre>
	:: Adding these lines will indicate both partitions should be mounted at boot to the directories we created. To mount the partitions without rebooting or entering individual mount commands, we can just run '''mount -a''' which will load and mount all partitions in the ''fstab'' file.		:: Adding these lines will indicate both partitions should be mounted at boot to the directories we created. To mount the partitions without rebooting or entering individual mount commands, we can just run '''mount -a''' which will load and mount all partitions in the ''fstab'' file.
	<li> Run the ~~'''mount -a'''~~ command now and verify both partitions are mounted.</li>		<li> Run the following command now and verify both partitions are mounted:
			<pre>mount -a</pre></li>
	</ol>		</ol>

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	: This indicates that the two partitions are mounted properly to the folders we created earlier. ''df'' is a powerful command as not only will it show you what is mounted where, but it also shows you how much disk space is used and how much space is left.		: This indicates that the two partitions are mounted properly to the folders we created earlier. ''df'' is a powerful command as not only will it show you what is mounted where, but it also shows you how much disk space is used and how much space is left.
	: The '''df''' command doesn't give the most easily readable disk or usage sizes by default.		: The '''df''' command doesn't give the most easily readable disk or usage sizes by default.
	<li> Add the ''-h'' option to the command like ~~'''df -h'''~~ to change the output to a "human readable" format and see what it looks like.</li>		<li> Add the ''-h'' option to the command like to change the output to a "human readable" format and see what it looks like.
	<li> Now, '''cd''' into ''/mnt/part1'' so you are on the ext4 partition you created. Then as root, run the command ~~'''~~cp -r /var/log ./~~'''~~</li>		<pre>df -h</pre> </li>
	<li> '''cd''' into the ''log'' folder, and run ~~'''~~du -h'''. </li>		<li> Now, '''cd''' into ''/mnt/part1'' so you are on the ext4 partition you created. Then as root, run the following command
			<pre>cp -r /var/log ./</pre> </li>
			<li> '''cd''' into the ''log'' folder, and run the following:
			<pre> du -h'''</pre> </li>
	: '''du''' is a command that allows you to view file usage in a tree format. Just like with '''df''' the ''-h'' flag tells '''du''' to output the usage in a "human readable" format, while the ''-a'' flag tells it to show you the results for all files, and not just for folders.		: '''du''' is a command that allows you to view file usage in a tree format. Just like with '''df''' the ''-h'' flag tells '''du''' to output the usage in a "human readable" format, while the ''-a'' flag tells it to show you the results for all files, and not just for folders.
	<li> Read the '''man du''' page and play around with using the '''du''' command across the file system. </li>		<li> Read the '''man du''' page and play around with using the '''du''' command across the file system. </li>

MikeTieden at 00:18, 27 January 2021

2021-01-27T00:18:10Z

← Older revision		Revision as of 00:18, 27 January 2021
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	:As you may have noticed when exploring ''/dev'', our VM setup uses ''sd'' devices for hard drives. Drives are identified by a letter such as ''sda'', ''sdb'', ''sdc'', etc. for the first, second, and third SATA drives on a system (including HDDs, CD/DVDs, SSDs, etc.). Each partition on the drive is then given a number starting with 0 for the first partition. So the first partition on the first disk, the full identifier for the partition would be ''/dev/sda0''.		:As you may have noticed when exploring ''/dev'', our VM setup uses ''sd'' devices for hard drives. Drives are identified by a letter such as ''sda'', ''sdb'', ''sdc'', etc. for the first, second, and third SATA drives on a system (including HDDs, CD/DVDs, SSDs, etc.). Each partition on the drive is then given a number starting with 0 for the first partition. So the first partition on the first disk, the full identifier for the partition would be ''/dev/sda0''.
	:You may also have noticed there is an ''sdb'' that currently has no partitions. We are going to format this drive into 2 partitions, format them, and then setup automatic mounting of the partitions.		:You may also have noticed there is an ''sdb'' that currently has no partitions. We are going to format this drive into 2 partitions, format them, and then setup automatic mounting of the partitions.
	<li> To start, run ~~'''~~cfdisk /dev/sdb''' as ~~root~~. ~~</li>~~		<li> To start, run the following as root:
			<pre>cfdisk /dev/sdb</pre> </li>
			:''cfdisk'' is a graphical version of ''fdisk'', which is a tool used to setup disk partitioning. Note that ''fdisk'' or any other partitioning software only sets up the MBR, and does not actually format the drive even though you can set a partition type identifier such as '''fat32''', '''Linux''', etc. Also notice how we tell ''cfdisk'' what drive we want to edit the partition on by appending the drive device "file" to the end of the command.
	: [[File:Test-screenshot.png\|250px]]		: [[File:Test-screenshot.png\|250px]]
	:''cfdisk'' is a graphical version of ''fdisk'', which is a tool used to setup disk partitioning. Note that ''fdisk'' or any other partitioning software only sets up the MBR, and does not actually format the drive even though you can set a partition type identifier such as '''fat32''', '''Linux''', etc. Also notice how we tell ''cfdisk'' what drive we want to edit the partition on by appending the drive device "file" to the end of the command.
	: Because our new drives contain no existing partitions we are asked what type of partition table to create.		: Because our new drives contain no existing partitions we are asked what type of partition table to create.
	<li> Choose to create a ''dos'' (aka ''MBR'') style partition table. </li>		<li> Choose to create a ''dos'' (aka ''MBR'') style partition table. </li>