Linux Learning Notes (1)

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date:2016-05-07 time:00:47:18 author:gaojiaxing

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1. What is Linux?

Linux is a set of operating systems, is a kind of short version of the distribution, the core is kernel.

Query the version number of the Kernal

[Email protected]:/# uname-r
4.4.0-21-generic

The first 4 represents the major version number, the second 4 is the minor version number (even-numbered stable, odd is the development version), and the third 0 represents the number of changes.

Author Linus Torvalds invented in 1991.

2. Linux Employment direction?

Management direction: Enterprise large amount of data saved on the server, need to be managed

Developing embedded Orientation:

3. What is a server?

Server general price is higher than PC, high hardware configuration, good heat dissipation. Based on the height of the 1u,2u,4u server, it is a device that provides computing services. DELL,HP,IBM brand servers are more common. See:

4. Mainstream Linux Systems

Redhat (charge), CentOS, Ubuntu,xubuntu,suse, etc.

5. Install the Linux system

Linux is relatively stable, the service is relatively good configuration, so it is often used as a background management tool, development environment. Because the entertainment is not strong enough to meet the needs of most computer players, the PC basically does not use Linux as the main operating system, so want to learn Linux, it is best to install virtual machine on the personal computer. VMware Workstation can be used on Windows, and VMware Fusion can be used on Mac OS. These two software word-of-mouth better, the virtual machine support is better, I am installed VMware Fusion. How to download the Linux image files, can visit their official website, also can go to www.mirrors.163.com, this is netease to provide us with the mirror address. Choose the release version according to your individual needs. Detailed installation procedures are not described here, note: Depending on the individual needs to choose whether to install the graphical interface. Note The choice of network connection method is common bridge (virtual machine IP address and real machine in the same network segment), NAT is the virtual machine to take advantage of the real computer network, sharing the IP address of the real machine, the real machine for the virtual machine traffic conversion.

6. Three types of remote connection servers

Putty, Xshell, Securecrt,macbook terminal comes with SSH remote connection command

7. Commands for Learning

1). LS Lists all files under the path

ls bin    Dev   initrd.img  lost+found  opt   run   srv  usrboot   etc   Lib         Media       proc  sbin  sys  varcdrom  home  lib64       mnt         root  snap  TMP  Vmlinuz

Bin: Store Normal executable commands

ETC: Storage directory for configuration files

Mnt,media: Mount point

OPT: third-party File installation directory

Root: Super User home Directory

Boot: System startup item

Home: Normal User home directory

Lost-found: Recycle Bin

Sbin: Super User can execute command

TMP: Temp file

2). Partitioning

Primary partition (P), extended partition (E)

Requirements: p+e<=4

Extended partitions can also partition many logical partitions

[Email protected]:/# fdisk-l        #查看磁盘情况

disk/dev/sda:20 GiB, 21474836480 bytes, 41943040 sectors
Units:sectors of 1 * bytes
Sector size (logical/physical): bytes/512 bytes
I/O size (minimum/optimal): bytes/512 bytes
Disklabel Type:dos
Disk identifier:0x6642f121

Our operating system is installed on a stat hard drive, and a represents the first hard drive.

If it's an IDE hard drive, that's disk/dev/hda.

3). Date Time

Date Sat   May 7 A:£ º

Calendar (operating month): Cal

Calendar for a specific month: Cal 09 2016

All calendars of a year: Cal 2016

3). View command History

4). Changing path CD (change directory) + path

View current path pwd (print working directory)

For example:

pwd/[email protected]:/# CD/Bin[email protected]:pwd/bin[email protected]: /bin# CD/Home[email protected]:

CD or CD ~ Back to the current user home directory

Cd.. Back to the top level directory

Cd. Current directory

CD-Back to the last directory

5) Shutdown Shutdown-h now

Restart Shutdown-r now or reboot

Linux Learning Notes (1)