Linux Learning Notes (1) Knowledge points and common management tools during the installation of Linux virtual machines

1. VMware related knowledge (1) Recommended VMware configuration:

Cpu	Frequency 1GHz or above
Memory	Above 1GB
Hard disk	Partition free space above 8GB

(2) VMware snapshot creation

The purpose of a snapshot is to save the existing state of the virtual machine so that it can be returned to the same state later. Snapshots Feature:① can quickly start a virtual machine, and ② a virtual machine system when it crashes, it can be quickly restored.

To create a snapshot, click the logo on the VMware toolbar and fill in the snapshot name as shown in:

To recover a snapshot, click the flag on the VMware toolbar, select the snapshot you created in the popup dialog box, and then click the Go button to open the snapshot.

(3) VMware create clones

Cloning can generate an operating system that is exactly the same as the current computer, and consumes less resources than two computers that are installed on a separate computer. Note: The cloned operating system is only the original mirror, so the clone machine will not be available when the original machine is deleted.

When you do this: on the menu bar, "virtual machines", "Management", "clone", then go to the Virtual Machine Cloning wizard

Note that subsequent operations typically use "linked clones" rather than "full clones," because the former consumes less resources .

2 Linux Overview (1) Types of partitions in Linux

Partition type	Characteristics
Primary partition	There can be up to 4
Extended partition	The ① can only have a maximum of 1 ② primary and extended partitions up to a total of 4 ③ cannot write data and can only contain logical partitions
Logical Partitioning	The area code is always starting from 5, such as SDA5,SDB5

(2) formatting

Formatting in Linux, also known as logical formatting, refers to writing specific data on a specific area of a disk based on a user-selected file system such as FAT16, FAT32, NTFS (three of which belong to Windows) and EXT2, EXT3, EXT4 (three of which belong to Linux). Carve out a piece of disk space for file allocation tables, table of contents tables, etc. for file management.

The main purpose of the format is to write to the file system , the two main tasks of writing to the file system are: ① thehard disk into a data block of equal size; ② Create an inode list for locating files .

(3) Hardware Device file name

Hardware	Device file name
IDE Hard disk	/DEV/HD[A-D]
SCSI/SATA/USB HDD	/DEV/SD[A-P]
Drive	/dev/cdrow or/dev/sr0
Floppy disk	/DEV/FD[0-1]
Printer (25-pin)	/DEV/LP[0-2]
Printer (USB)	/DEV/USB/LP[0-15]
Mouse	/dev/mouse

(4) partition file device name

The partition file device name is the partition number that is added to the device file name of the hard disk. such as IDE hard disk interface:/DEV/HDA1,SCSI, SATA hard disk interface:/dev/sda2. Note: Currently, the IDE, SCSI hard disk interface is now very rarely used, the current use of more SATA, because the latter is faster than the previous two.

(5) Mounting

VMware must partition when installing Linux virtual machine:① "/" (root partition) ②swap partition (swap partition size is twice times of memory, but not more than 2G; can be a virtual partition, so there is no mount point)

Recommended partition is:/boot(allocation size 200M, save data at system startup)

The file system in Linux is roughly as follows:

As you can see, the subdirectories of the root directory can be stored on different disk spaces .

(6) Installation log

①/root/install.log: Stores the packages and their version information installed in the system

②/root/install.log.syslog: Stores the event records that were left during the installation

③/ROOT/ANACONDA-KS.CFG: The option information set during installation is recorded in the format of the Kickstart configuration file, which can be used for automatic installation of multiple server systems (installation depends on the file)

3 Network connection modes in VMware

VMware Virtual Software provides three network connectivity modes: Bridging, NAT, and host-only, as shown in:

Here are three different modes.

① bridging mode (bridged)

In this mode, the VMware virtual machine uses the real network card, not only can communicate with its own real machine, but also can communicate with other computers in the same network segment on the LAN. Therefore, you need to manually configure the virtual machine with an IP address, subnet mask, and the same network segment as the host. If you want to use VMware to create a new virtual service area within the LAN, and to provide network services for LAN users, select bridging mode.

② Network Address translation mode (NAT)

In this mode, the virtual system uses the NAT function to access the public network through the host's network, that is, the use of NAT mode can be used to access the Internet in the virtual machine. In this mode, the TCP/IP configuration of the virtual machine system is provided by the DHCP server of the VMNET8 virtual network and cannot be modified manually, so the virtual machine cannot communicate with other real hosts on the LAN. The biggest advantage of this mode is that the virtual machine access to the Internet is very easy, without any other configuration, only the host can access the Internet properly.

③ Host-only mode (host-only)

In this mode, the VMware virtual machine communicates with the host via the fake Nic VMnet1, but the virtual machine and the real network are isolated.

4. Linux Management Tools

There are many remote management tools available in Linux, and the following are some of the tools used in learning.

(1) SecureCRT

SECURECRT can be implemented under Windows to the UNIX or Linux server host, only need to simply configure. Specific configuration and use of the method, you can refer to: 7.2_SECURECRT using the tutorial, SECURECRT configuration detailed graphics tutorial.

Here is the installation of the Chinese version of Linux, the use of SECURECRT when there is a Chinese garbled solution.

① Click Options on the menu bar and select the "Session Options" option.

② Select "Font" in "Appearance" in "Terminal", select a Chinese font in the pop-up dialog, then select "Chinese _gb2312" in the "character set" and click "OK".

③ then select the encoding "UTF-8" in the "Character Encoding" option and click "OK".

(2) WINSCP

WINSCP is a file copy tool that allows you to copy files between Windows and Linux. Easy to install and use, refer to: WINSCP How to use the tutorial

(3) Putty

is also a powerful remote login tool, the specific download, installation and use can refer to Putty Chinese station.

Linux Learning Notes (1) Knowledge points and common management tools during the installation of Linux virtual machines