Features of VMware:
1. You can use more than two operating systems on the same PC without partitioning or rebooting
2. The local system can communicate with the virtual machine system network
3. You can set and modify the hardware environment of the virtual machine operating system at any time
VMware can install multiple systems with the same function as a physical machine, and modify the hardware environment at any time, but the memory is up to half of the physical machine.
Official website www.vmware.com
The new version mainly faces enterprise updates and takes up more resources. 7.0 cannot be used on WIN7.
You can use snapshots to save the current state of the virtual machine operating system, unlike physical machines that need to be reinstalled, which is conducive to learning and convenient.
Recommended configuration
CPU 1GHz memory more than 1GB hard disk partition free more than 8G, install LINUX requires 2G memory.
It is not recommended to install to the C drive. The data on the first C drive will become larger and larger. When the second reinstallation, many software do not need to be reinstalled.
Do not join the experience program, suspected of stealing data
Installation speed depends on computer performance
After installation, 2-3G of space is required.
Select boot to start, many functions can be used.
uninstall vmware
vm_install_clear thoroughly cleans up the junk files formed by uninstalling the virtual machine, including cleaning the registry,
Do not directly delete the location where vmware is directly installed in the file, because there are a lot of junk files, the next time you install vmware, it will think that you have installed it, but at this time vmwate has lost its function.
Deleting using the control panel is also not a very good solution
Network selection:
Bridging Direct virtual machine and real machine communication
NAT uses the vmware8 network card to communicate with the real machine and can access the Internet
The host communicates with vmware1 and cannot access the Internet
NAT and host can only communicate with the local machine and cannot communicate with other machines on the network segment
NAT and Host-only use virtual network cards VMnet8 and VMnet1 respectively, which can only communicate with the real machine and cannot communicate with other network devices on the local area network.
Bridging: The virtual machine and the real machine communicate using the real local network card. Simple configuration and direct communication, but the virtual machine occupies an ip of the real machine network segment
Centos download address: http://wiki.centos.org/Download or http://www.centoscn.com/CentosSoft/
start installation:
Writing to the file system divides the entire partition into data blocks of equal size, and creates a file information table (I node, permission, modification time) in the partition list. Before writing to the file system, data must be cleared. In the past, it was believed that formatting is simply clearing data, and clearing is only one thing that must be done in order to write to the file system.
The MBR partition can be divided into four primary partitions at most.
If GPT is used, there is no limit to the file system: ext4 and ntfs are the most advanced file management systems at present;
4kb divides the entire hard disk space, formatting is to construct a file system, 4kb is called block!
In storage: each storage area has its own id number, access rights, and date modification time.
1. There can only be up to 4 primary partitions + extended partitions
2. The fundamental purpose of formatting is to write to the file system (fat16/fat32/ntfs...)
For linux, formatting is actually dividing the entire partition into data blocks of equal size; a two-dimensional table is established in the partition list, which records the ID number (I node/inode), modification time, and permissions of each file.
Windows file system format fat16 (maximum hard disk 2GB) fat32 maximum hard disk 16T maximum file 4GB
NTFS unlimited
linux file system format EXT4
Under Windows, A and B are used as the drive letter of the soft partition, and C is used as the drive letter of the first main partition, so it can be divided into 23 sub-partitions at most.
The function of formatting: The fundamental purpose of partitioning the hard disk is to write to the file system. FAT16: The maximum supported 2G partition FAT32 single file uppercase cannot exceed 4G, the supported partition size is 16TB, NTFS supports larger single file supports larger partition.
Formatting purpose: 1. Divide the entire partition into equal-sized data blocks, and the default minimum storage unit block size is 4KB. 2. Partition list: have I node (ID number), modification time, permission, save location. Take out the clothes first before you can play the interval, so the formatting needs to clear the data.
1. Disk partition: Use the partition editor to divide several logical storage spaces on the disk. Once the disk is divided into several partitions (Partition), different types of directories and files can be stored in different partitions.
2. The advantage of partition: improve the efficiency of file search and read and write.
3. Partition type (applicable to all systems):
Primary partition: can only be divided into 4 at most, which is determined by the structure of the hard disk (the hard disk is divided into sectors of equal size, each sector is 512 bytes, of which 446 bytes are used to record boot information, and the remaining 64 Each 16 bytes of 64 bytes represents a partition, so it can only represent 4 partitions at most, so if the structure of the hard disk remains unchanged, the main partition can only be divided into 4 at most). Each primary partition has its own independent boot block, which can be set as the boot area with fdisk.
Extended partition: One primary partition can be used as an extended partition, that is, three primary partitions and one extended partition, totaling 4 partitions; there can only be one extended partition in a hard disk; extended partitions cannot write data and can only be used to contain logic partition. Distinguishing between extended partitions and logical partitions is the most important way to break through the only four primary partitions.
Logical partition: There can be multiple, there is no independent boot block, and fdisk cannot be used as the boot area.
Supplement: MBR and GPT
4. Formatting: Also known as logical formatting, it refers to the file system selected by the user (eg: FAT16 (maximum support 2GB partition), FAT32 (single file size cannot exceed 4GB, maximum support 16TB partition), NTFS, EXT2 , EXT3, EXT4 (centos6 default file system), etc.), write specific data in a specific area of the disk, and draw a piece of disk space in the partition for storing file allocation tables, directory tables, etc. for file management.
Misunderstanding analysis: The purpose of formatting is not to clear data, its fundamental purpose is to write to the file system, but the original data will be cleared first when formatting.
Formatting purpose: Find and read data faster.
Formatting specific operations:
Divide the entire partition into blocks of equal size, each block is 4KB by default, and the minimum storage file is 1KB, 2KB or 4KB manually. Assuming that a 10KB file is stored, three data blocks will be used. The three data blocks are not necessarily consecutive. Even if the last data block is not full, no other files can be stored.
A two-dimensional table is established in the partition list, which records the id number of the file (that is, the file is placed in those databases, called i-node), the modification time of the file, and the access authority of the file. When operating files, first access this two-dimensional table for permission matching.
1. Different disk partitioning process between Windows and Linux
Windows: Partition --> Format --> Assign drive letter
Linux: partition --> format --> give each partition "device filename" --> assign mount point
2. Device file name: Everything in Linux is a file, including hardware, users, etc. The file name of the hardware is called "the file name of the hardware device". The file name of the hardware device, as the standard name of the hardware, is automatically detected and assigned by Linux. The hardware device files are located in the dev folder (dedicated for placing hardware device files) under the root directory ("/" represents the root directory, the highest level directory) in the directory, that is, under the "/dev" folder.
Device file name assignment rules for partitions:
hd stands for IDE interface, sd stands for SCSI interface or SATA interface;
a represents the first hard disk, if there are multiple hard disks b represents the second hard disk, c represents the third hard disk, and so on;
1 represents the first partition on a hard disk, 2 represents the second partition of the hard disk, 3 represents the third partition of the hard disk, and so on. The number 1234 can only represent the primary partition or extended partition, and the number of the logical partition. Allocate from 5, maximum partition number 16
/dev/sda1 The first partition of the first SATA interface hard disk
IDE interface, old-fashioned hard disk interface, slow transmission speed, theoretical speed 133MB/S
SCSI interface, old server hard disk interface, theoretical speed 200MB/S
SATA interface (window hard disk), currently used hard disk interface, divided into three generations, the theoretical speed of SATA3 is 500MB/S
3. Mount point: Refer to the concept of drive letter in Windows to understand. Windows uses letter identifiers to specify files and directories on this partition, while Linux uses directories as mount points (drive letters)
Most directories can be used as mount points (except for some directories that must be placed in the same partition as the root directory, otherwise the system will not be able to start), including directories you create manually.
Must be partitioned:
Root partition / (mount point root directory, all other data should be saved in the root directory, if the root directory has no hard disk space, a lot of data under the root will have no place to store)
swap partition (swap partition, which can be understood as virtual memory. When the real memory is insufficient, the hard disk space in the swap partition can be used as memory. If the memory is less than or equal to 4GB, it is recommended that swap allocate twice the memory. If the memory is greater than 4GB, it is recommended to The swap space is equal to the memory, no mount point is required)
Recommended partition:
Boot partition, recommended 200MB (mount point /boot directory, /boot stores relevant data for system startup, if it is not partitioned separately, it will be stored in the same storage space as the root partition. If the root partition is full, it will be stored in the same storage space. cause the system to fail to boot)