Centos8.0 installation on a virtual machine

First, prepare the host

    In order to train and deploy Hadoop eco tuning techniques, you need three virtual machine deployment Hadoop cluster environment, to ensure HA, that is, there is no single point of failure main services, perform basic functions, parameter adjustments are small memory model.

1.1, ready to install package

The host operating system Win7 SP1, memory 16G, 256G of disk to disk SSD

1) virtual machine: VMware® Workstation 15 Pro 15.5.0 build-14665864 Chinese version

2) Linux system: CentOS-8-x86_64-1905-dvd1.iso (Centos 8.0)

1.2, configure the network

After installing VMware, in addition to the host a total of three wireless network card, namely:

1) local network card, 192.168.3.127, mask 255.255.255.0

2) Vmnet1 (used to support host only mode), 192.168.121.1, mask 255.255.255.0

3) Vmnet8 (for supporting the NAT [. 1] mode), 192.168.154.1, 255.255.255.0 mask

In this study, we deploy the virtual machine using NAT mode network.

Start VMware Workstation Pro, click Edit -> Virtual Network Editor ...

 

1.2.1 View NAT settings

Click "NAT Settings (S) ...", you can view the NAT settings

 

I.e. NAT gateway is 192.168.154.2, set in the virtual machine 192.168.154 IP segment in the mask is set 255.255.255.0 Gateway 192.168.154.2, virtual machine can access the external network.

1.2.2 Changing settings

If the virtual LAN and IP Vmnet1 modify Wmnet8, the need to modify the information and vmware pro workstation card "Change Settings"

You can click Change settings, note that this requires administrator can set up and will pop up "User Account Control" dialog box for confirmation.

 

You can click on the "NAT Settings ..." Set Gateway

 

1.3, server configuration time

The virtual machine host as a time server.

• Right-click "Computer" on the desktop, select "Manage" and then select "service." Will automatically (delayed start) Windows startup type Time Service
• "Start" -> "Run" -> type "regedit" to open the registry.
  • HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ W32Time \ TimeProviders \ NtpServer NetSerVer the setting values ​​of 1 Enabled, if no increase Enabled Enabled name, type REG_DWORD, item value of 1.
  •  HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ W32Time \ Config \ AnnounceFlags set to 5 (5 represents a stable source, default 10)
• If the notebook is unplugged network cable, because the "media probe (Media Sense)" Win7 technology will automatically shut down network service, you can modify the registry to deceive OS continue to provide services
  • HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters，添加子项
    •   名称：DisableDHCPMediaSense
    •   Data Type: REG_DWORD (Boolean)
    •   Value: 1
  •  Side effects, the notebook hibernation, from a wireless network environment to another wireless network environment, you cheated because DHCP, does not automatically apply the new notebook wake IP, resulting in can not connect wireless network, you need to manually start it and prohibit wireless network, other DHCP network will also need similar operations.
• Restart Windows Time service, you can use the host as an NTP server.
  • Note that the default Windows Time service is Automatic (Delayed Start), which applies to desktop and notebook models, if a Windows server, to modify the "auto" mode.
  • Foreign only provide services only time physical NIC, Linux time server IP must correspond to the physical IP network card, in this case the time server IP address is 192.168.3.127

 

1.4, Centos8 commonly used commands

root run

# Systemctl start foo # run a service

# Systemctl stop foo # stop a service

# Systemctl restart foo # restart a service

# Systemctl status foo # display a service (whether running or not) state

# Systemctl enable foo # enable a service at boot

# Systemctl disable foo # disable a service at boot

Are # systemctl is-enabled foo # View service boot

# Reboot # reboot the host

# Init 0 # immediate shutdown

Second, the installation Centos8.0

2.1, ready to configure the virtual machine foundation

 

 Select "Custom" and click "Next"

 

  Click "Next"

 

  Select "install the operating system later" and click "Next"

 

  Select "Red Hat Enterprise Linux 8 64 Bits", click "Next"

 

  According to individual needs, enter the name of the virtual machine, you can also select the directory to store the virtual machine, click "Next"

 

  Select the number of processors and the number of nuclear host according to the situation and your specific plan, click "Next"

 

  Select or enter the memory for a virtual machine using the host according to the situation and your specific plan, click "Next"

 

  According to the specific needs of select network mode, in this case you need to access the Internet through the host, but also prohibited outside the network to access the virtual machine, so the use of NAT mode, click "Next"

 

  Recommended by automatic mode, click "Next"

 

  Recommended by automatic mode, click "Next"

 

  Select "Create a new virtual disk", click "Next"

 

  Depending on the needs of the disk, enter the size of the disk, because the clone as a seed, be careful not to choose to allocate all the disk space immediately. In order to facilitate copying, select "See Split virtual disk into multiple files." Click "Next"

 

  Click "Next"

 

  Optimize, delete unnecessary hardware USB, sound card, printer, and so on.

Click the "Custom Hardware"

 

  Stepwise selection USB controller, sound card, printer, click "Remove"

Setting a display to save resources, cancel "accelerated 3D graphics", set a resolution of 1280 × 1024

 

  Set the drive using the ISO file Centos8

 

  Click "Close" Revert

 

  Click "Finish." The end of the preparatory phase of the virtual machine

 

2.2, start the virtual machine

Connect the text, click on the "open this virtual machine"

 

  Note: switch a virtual machine interface and host of characters to press "Ctrl" + "Alt" key

Select the cursor to "Install CentOS Linux 8.0.1905", carriage return

After a quick scroll through a lot of text messages, graphical interface.

 

  Click "Continue", displays summary information node, in this interface, we need to set up a collection of software, general information about disk partitions, date, network and so on.

 

  2.2.1, set up the network

 

  Drag the button, select the network status to "On"

 

  At this point the IP set to DHCP mode, click on the "Configure", set manually assigned IP

 

  "General" page, select the option "Automatically Connect to this network ...", ensure that the automatic start this network settings.

 

  Set in IPV4 Settings in the network to manually specify static IP, according to earlier agreement, the gateway is specified as 192.168.154.2, DNS specify the circumstances the country, such as Tianjin Unicom DNS is 202.99.96.68

 

  Click "Save" to return to the previous interface

 

  The contents of the input box after "Host Name" is planning to modify the server domain name, such as "Hadoop.centos8.cn", click on "Apply"

 

 Click "Done" return to the previous screen.

2.2.2, set the date

At this time, the network had been connected, you can set the time and the time the server at the same time.

First select the correct time zone. Can be selected on the map by selecting the drop-down menu with the mouse.

 

  Now "Network Time" in the "On" state, click the Settings button next to

 

Increase the time server host, and to cancel the default server centos.pool.ntp.org

 

  Note that the status "Working", if it is , represents the normal time and can access the server, and vice versa if it is necessary to check and set the time server network settings.

Select "OK" to confirm the setting network time server.

Select "Done" Revert

2.2.3, configure disk space

 

  Virtual machines can automatically select the partition by its relatively simple rules, divided into boot, root, swap, main space in the root partition. If it is a physical machine or have special needs, you can choose "Custom"

2.2.4, select the package installed

 

  As a server, generally do not select the GUI, to conserve system resources occupied.

 

  In order to develop and debug, usually selected "Performance Tools" and "Development Tools" can be, other follow-up package can be installed when required by yum.

 Click "Done" Revert

2.2.5 to start the installation

 

  Click "Begin Installation" to begin the installation

 

2.2.6, set the user name and password

 

  Note that if the root password is too simple, it requires two confirmation ( "click Down"), as shown below.

 

  You can then create a normal user

 

  Similarly, if the password is too weak, you need to click twice "Done"

 

 

  Continue to wait for the completion of the installation progress

 

2.2.7, the installation is complete restart

 

  Click "Reboot" to restart

 

2.3 General Configuration

2.3.1, Configuring SecureCRT

 

  Create a file named hadoop of Session, IP address 192.168.154.8, double-click the connection to the server

The first connection dialog box, note: each virtual machine has a separate Hash values.

 

  Select "Aceept & Save"

 

  Enter the correct user name and password. Note: Try not to log in as root user.

 

  Session options can be set after a successful login. Menu "Options" -> "Session Options ..."

 

  Color scheme and configure the rolling area of ​​the buffer

  Configuring Character Sets and display fonts

2.3.2, set the ISO or DVD software source source software

2.3.2.1, set the DVD source software

2.3.2.1.1 loading optical drive

Ensure that the virtual machine settings in the device status is "Connected."

 

  # Switch to the root user

its

#Create a directory

mkdir /mnt/centos8

# Mount

mount /dev/sr0 /mnt/centos8/

 # Uninstall command

umount /mnt/centos8 

2.3.2.1.2, automatically mount cdrom

vi / etc / fstab

Add the line

/dev/sr0 /mnt/centos8 iso9660 auto,ro 0 0

2.3.2.1.3, create a local source

cd /etc/yum.repos.d/

ll

-rw-r--r--. 1 root root  731 Aug 14 14:42 CentOS-AppStream.repo

-rw-r--r--. 1 root root  712 Aug 14 14:42 CentOS-Base.repo

-rw-r--r--. 1 root root  798 Aug 14 14:42 CentOS-centosplus.repo

-rw-r--r--. 1 root root 1320 Aug 14 14:42 CentOS-CR.repo

-rw-r--r--. 1 root root  668 Aug 14 14:42 CentOS-Debuginfo.repo

-rw-r--r--. 1 root root  756 Aug 14 14:42 CentOS-Extras.repo

-rw-r--r--. 1 root root  338 Aug 14 14:42 CentOS-fasttrack.repo

-rw-r--r--. 1 root root  928 Aug 14 14:42 CentOS-Media.repo

-rw-r--r--. 1 root root  736 Aug 14 14:42 CentOS-PowerTools.repo

-rw-r--r--. 1 root root 1382 Aug 14 14:42 CentOS-Sources.repo

-rw-r--r--. 1 root root   74 Aug 14 14:42 CentOS-Vault.repo

Check which sources are available for use

grep -lrn "enabled=1"

CentOS-AppStream.repo

CentOS-Base.repo

CentOS-Extras.repo

The renamed source can be used

mv CentOS CentOS Base.repo Base.repo.bak

mv CentOS-AppStream.repo CentOS-AppStream.repo.bak

mv CentOS-Extras.repo CentOS-Extras.repo.bak

Editing Base and App Stream source

vi CentOS Base.repo

[BaseOS]

name=CentOS-$releasever - Base

baseurl = file: /// mnt / centos8 / BaseOS

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

enabled=1

Save and exit

I saw CentOS-AppStream.repo

[AppStream]

name=CentOS-$releasever - AppStream

baseurl = file: /// mnt / centos8 / AppStream

gpgcheck=1

gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

enabled=1

Save and exit

Check local source

yum clean all

yum list | grep gcc style list is shown below

gcc.x86_64                 8.2.1-3.5.el8  @AppStream

gcc-c++.x86_64             8.2.1-3.5.el8  @AppStream

gcc-gdb-plugin.x86_64      8.2.1-3.5.el8  @AppStream

libgcc.x86_64              8.2.1-3.5.el8  @anaconda

gcc-gdb-plugin.i686        8.2.1-3.5.el8  AppStream

gcc-gfortran.x86_64        8.2.1-3.5.el8  AppStream

gcc-offload-nvptx.x86_64   8.2.1-3.5.el8  AppStream

libgcc.i686                8.2.1-3.5.el8  BaseOS   

2.3.2.2, setting the software source ISO

2.3.2.2.1 loading iso file

#Create a directory

mkdir /mnt/centos8

# Copy iso file to a specific directory, such as /opt/kvm/data/iso/CentOS-8-x86_64-1905-dvd1.iso

# Mount

mount -o loop /opt/kvm/data/iso/CentOS-8-x86_64-1905-dvd1.iso /mnt/centos8

# Uninstall command

umount /mnt/centos8 

2.3.2.2.2, automatically mount iso file

vi / etc / fstab

Add the line

/opt/kvm/data/iso/CentOS-8-x86_64-1905-dvd1.iso /mnt/centos8 iso9660 auto,ro 0 0

2.3.2.2.3, create a local source

With 2.3.2.1.3, create a local source

2.3.3 Check time synchronization

The installation process has been set up time and time synchronization server, where only check the configuration file and whether to start service

cat /etc/chrony.conf see the following line:

server 192.168.3.127 iburst

The following command can be Centos8 of chrony time the server is restarted, set to start automatically, view the status

systemctl restart chronyd

systemctl enable chronyd

systemctl status chronyd

Check synchronization and time server Linux case

chronyc sourcestats –v

2.3.4 simplify security settings

Turn off the firewall

# Check the firewall status

systemctl status firewalld.service 

# Turn off the firewall

systemctl stop firewalld.service 

# Disable the firewall boot

systemctl disable firewalld.service 

 

Close SELINUX

# vi /etc/selinux/config

Edits:

# SELINUX = enforcing # comment out

SELINUX = disabled # increase

Save and exit, take effect after the next restart

If you want to make the configuration take effect immediately, execute

setenforce 0  

2.3.5, the management pack mounting portion

yum install expect redhat-lsb-core -y

verification

lsb_release –a

LSB Version:    :core-4.1-amd64:core-4.1-noarch

Distributor ID: CentOS

Description:    CentOS Linux release 8.0.1905 (Core)

Release:        8.0.1905

Codename:       Core

Core edition

uname –a

Linux hadoop.centos8.cn 4.18.0-80.el8.x86_64 #1 SMP Tue Jun 4 09:19:46 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

2.3.6, Samba deployment

yum install samba samba-client -y

It has closed the firewall so the most complex issues will not appear

we /etc/samba/smb.conf

The default shared user directory

Also because there is no printer installed, it deletes the shared printer's configuration

Delete [printers] [print $]

Start Service

systemctl enable smb

systemctl enable nmb

systemctl restart smb

systemctl restart nmb

Setting an Access Password

smbpasswd -a ansible

Set the host win7

C:\Windows\System32\drivers\etc\hosts

192.168.154.8 hadoop

192.168.154.11 hadoop11.centos8.cn  hadoop11

192.168.154.12 hadoop12.centos8.cn  hadoop12

192.168.154.13 hadoop13.centos8.cn  hadoop13

Access hadoop in win7

 

  You can access the home directory of the ansible

Third, the clone

3.1, clone node

The shutdown command init 0, after shutdown completes start cloning

Select the virtual machine hadoop, click menu -> Virtual Machine -> Administration -> Clone ...

 

  Click "Next"

 

  Click "Next" to continue

 

  If the new virtual machine running on the machine, in order to save disk, you can select "create a linked clone," whereas if you want to copy to a different server, be sure to "create a full clone."

Click "Next" to continue

 

  Enter a name for the cloned virtual machine, click "Finish" to start cloning the virtual machine.

 

  Click "Close"

3.2, modify the IP address

Start cloning the resulting virtual machine hadoop11

Set the IP and hostname

IP 在vi /etc/sysconfig/network-scripts/ifcfg-ens160

vmware does not regenerate UUID, avoid duplication, need to update this UUID

UUID="…"

Call uuidgen produced a new uuid, replace the original string

Such as:

uuidgen

bd83dded-76d2-4d23-8799-134f8b7eb984

Modify the IP address

IPADDR="192.168.154.8"

for

IPADDR="192.168.154.11"

3.3, modify the host name IP

vi / etc / hostname

hadoop.centos8.cn

change into

hadoop11.centos8.cn

3.4 Restart

Repeat 3.1-3.4 complete hadoop12, cloning and disposed hadoop13

Fourth, the main difference Centos8 and Centos7

4.1, network services

Centos8 / RHEL8 network management-related services has been transferred to NetworkManager, not installed by default network services.

systemctl status NetworkManager can check the service status.

Note: Modifying IP, if only to modify the network card configuration, and then restart NetworkManager, it is not feasible. The right way is to restart the network card:

1, nmcli connection down ens160 stop card

2, nmcli connection up ens160 start card

Note: At this point do not pay attention to the card is a remote management card that way.

Modify the configuration file, there are three

1, we

2, nmcli connection modify ens160 (ens160 network card name)

3, nmtui character editing interface

If, as Centos7 as the use of network services can be installed with yum

yum install network-scripts

But according to official information, future network services will be completely removed from the distribution package.

---

[1] NAT: Network Address - Search.com, network address translation, can achieve a bandwidth sharing and security.