Installation and use of Ubuntu 18.04 Server version (picture and text)

# cat /etc/hostname 
hechunping

# sed -i '/GRUB_CMDLINE_LINUX=/s/"$/net.ifnames=0 biosdevname=0"/' /etc/default/grub
# update-grub
Sourcing file `/etc/default/grub'
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-4.15.0-55-generic
Found initrd image: /boot/initrd.img-4.15.0-55-generic
done
# reboot
# sed -i 's/ens33/eth0/' /etc/netplan/01-netcfg.yaml

# By default, Ubuntu does not allow remote ssh for root users. If you need to allow remote ssh for root users in actual scenarios, you need to set a root password and edit the /etc/ssh/sshd_config file as follows:
~$ sudo vim /etc/ssh/sshd_config
32 #PermitRootLogin prohibit-password #Default is to prohibit login 33 PermitRootLogin yes #Change to allow login 57 #PasswordAuthentication yes
58 PasswordAuthentication yes #Turn on password authentication. In fact, the default is to allow login via password authentication~$ sudo su - root #Switch to the root user environment~# passwd #Set passwordEnter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
~# systemctl restart sshd #Restart the ssh service and test the remote ssh connection of the root user

Official documentation: https://netplan.io/

Starting from Ubuntu 17.10, the fixed IP configuration in /etc/network/interfaces has been abandoned and replaced with the netplan method. The configuration file is: /etc/netplan/01-netcfg.yaml

# Static IP configuration method for Ubuntu 17.04 and earlier:
~# cat /etc/network/interfaces
root@hechunping:~# cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback
auto eth0 #Network card auto-start, write the actual network card name for which you want to configure the IP iface eth0 inet static #Configure static IP, write the actual network card name for which you want to configure the IP address 172.18.3.12 #IP address netmask 255.255.0.0 #Mask gateway 172.18.0.1 #Gateway dns-nameservers 223.6.6.6 #DNS
dns-nameservers 223.5.5.5
#Restart network service~# /etc/init.d/networking restart
~# systemctl restart networking.service

root@hechunping:~# cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
   addresses: [192.168.7.132/24]
   gateway4: 192.168.7.2
   nameservers:
    addresses: [223.6.6.6]
root@hechunping:~# netplan apply

# cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
   addresses: [172.20.7.34/16]
   gateway4: 172.20.0.1
   nameservers:
    addresses: [223.6.6.6]
  eth1:
   dhcp4: no
   addresses: [192.168.7.34/24]
   routes:
    - to: 172.20.0.0/16
     via: 192.168.7.2
# netplan apply

# cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
 Bridges:
  br0:
   dhcp4: no
   addresses: [172.20.7.34/16]
   gateway4: 172.20.0.1
   nameservers:
    addresses: [223.6.6.6]
   interfaces:
    -eth0
# netplan apply

Bridge br0 and br1 to eth0 and eth1 respectively.
# cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
  eth1:
   dhcp4: no
 Bridges:
  br0:
   dhcp4: no
   addresses: [172.20.7.34/16]
   gateway4: 172.20.0.1
   nameservers:
    addresses: [223.6.6.6]
   interfaces:
    -eth0
  br1:
   dhcp4: no
   addresses: [192.168.7.34/24]
   routes:
    - to: 172.20.0.0/16
     via: 192.168.7.2
   interfaces:
    -eth1
root@hechunping:~# netplan apply

The bridge command needs to be installed in advance. The two network cards use the same network mode. # cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
  eth1:
   dhcp4: no
 bonds:
  bond0:
   interfaces:
    -eth0
    -eth1
   addresses: [172.20.7.34/16]
   gateway4: 172.20.0.1
   nameservers:
    addresses: [223.6.6.6,223.5.5.5]
   parameters:
    mode: active-backup
    mii-monitor-interval: 100
#poweroff
# netplan apply

NIC teaming is used to provide NIC interface redundancy, high availability, and port aggregation, while bridged NICs are used for services that require bridged devices.

# cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
  eth1:
   dhcp4: no
 bonds:
  bond0:
   interfaces:
    -eth0
    -eth1
   parameters:
    mode: active-backup
    mii-monitor-interval: 100
 Bridges:
  br0:
   dhcp4: no
   addresses: [172.20.7.34/16]
   gateway4: 172.20.0.1
   nameservers:
    addresses: [223.6.6.6,223.5.5.5]
   interfaces:
    -bond0
# netplan apply

Realize network card binding in multi-network situation. Two network modes are used here: bridging (eth0, eth1) and NAT (eth2, eth3). # cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
  eth1:
   dhcp4: no
  eth2:
   dhcp4: no
  eth3:
   dhcp4: no
 bonds:
  bond0:
   interfaces:
    -eth0
    -eth1
   addresses: [172.20.7.34/16]
   gateway4: 172.20.0.1
   nameservers:
    addresses: [223.6.6.6,223.5.5.5]
   parameters:
    mode: active-backup
    mii-monitor-interval: 100

  bond1:
   interfaces:
    - eth2
    -eth3
   addresses: [192.168.7.34/24]
   parameters:
    mode: active-backup
    mii-monitor-interval: 100
   routes:
    - to: 172.20.0.0/16
     via: 192.168.7.2
# netplan apply

# cat /etc/netplan/01-netcfg.yaml 
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
 version: 2
 renderer: networkd
 ethernets:
  eth0:
   dhcp4: no
  eth1:
   dhcp4: no
  eth2:
   dhcp4: no
  eth3:
   dhcp4: no
 bonds:
  bond0:
   interfaces:
    -eth0
    -eth1
   parameters:
    mode: active-backup
    mii-monitor-interval: 100

  bond1:
   interfaces:
    - eth2
    -eth3
   parameters:
    mode: active-backup
    mii-monitor-interval: 100
 Bridges:
  br0:
   dhcp4: no
   addresses: [172.20.7.34/16]
   gateway4: 172.20.0.1
   nameservers:
    addresses: [223.6.6.6,223.5.5.5]
   interfaces:
    -bond0
  br1:
   dhcp4: no
   addresses: [192.168.7.34/24]
   routes:
    - to: 172.20.0.0/16
     via: 192.168.7.2
   interfaces:
    -bond1
# netplan apply

Alibaba Cloud Warehouse Address: https://developer.aliyun.com/mirror
USTC: http://mirrors.ustc.edu.cn/help/ubuntu.html
Tsinghua University: https://mirror.tuna.tsinghua.edu.cn/help/ubuntu/
Huawei: https://mirrors.huaweicloud.com/

###### Tsinghua source configuration######
Ubuntu's software source configuration file is /etc/apt/sources.list. Make a backup of the file that comes with the system, and replace the file with the following content to use the TUNA software source image.
# cd /etc/apt/
# cp -p sources.list sources.list.bak
# vim sources.list
# By default, the source mirror is commented to improve the apt update speed. If necessary, you can uncomment it yourself. deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse

# Pre-release software source, not recommended to enable # deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
# apt update #Update the local package list index. This must be executed after modifying the apt repository.

###### Ali source configuration######
# sed -i 's/cn.archive.ubuntu/mirrors.aliyun/' /etc/apt/sources.list
# apt update #Update the local package list index. This must be executed after modifying the apt repository.

apt list #apt lists warehouse packages, equivalent to yum list
apt search NAME #Search for installation packages apt show apache2 #View detailed information about an installation package apt install apache2 #Install a package online apt remove apache2 #Uninstall a single package but keep the configuration file apt autoremove apache2 #Remove the installation package and resolve dependencies apt update #Update the local package list index, which must be executed after modifying the apt repository
apt purge apache2 #Uninstall a single package and delete the configuration file apt upgrade #Upgrade all installed packages that can be upgraded to a new version apt full-upgrade #Upgrade the entire system and remove old packages if necessary.
apt edit-sources #Edit source file apt-cache madison nginx #Check which versions of the software packages in the repository can be installed apt install nginx=1.14.0-0ubuntu1.6 #Specify the specific version to install when installing the software package

rpm: RPM (Red Hat Package Manager) is a package management system based on Red Hat's Linux Distribution. It also refers to the rpm package itself. RPM is used to manage rpm packages (such as installation, uninstallation, and upgrades).
"dpkg" is the abbreviation of "Debian Packager", a package management system specially developed for "Debian" to facilitate software installation, updating and removal. All "Linux" distributions derived from "Debian" use "dpkg", such as "Ubuntu", "Knoppix", etc.

dpkg -i gitlab-ce_11.9.8-ce.0_amd64.deb #Install a software package dpkg -r gitlab-ce #Delete a software package and keep the configuration file dpkg -r -P gitlab-ce #Delete a software package without keeping the configuration file dpkg -I gitlab-ce_11.9.8-ce.0_amd64.deb #View the software package information dpkg -c gitlab-ce_11.9.8-ce.0_amd64.deb #View the files and directory contents in the software package dpkg -l #List all software installed on the local machine

# pwd
/usr/local/src
Unzip the binary file and set up a soft link:
# tar xf jdk-8u212-linux-x64.tar.gz
# ln -sv /usr/local/src/jdk1.8.0_212 /usr/local/jdk
Configure environment variables:
# vim /etc/profile
export JAVA_HOME=/usr/local/jdk
export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH
export CLASSPATH=.$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib:$JAVA_HOME/lib/tools.jar
Re-import the environment variables and verify:
# source /etc/profile
# java -version
java version "1.8.0_212"
Java(TM) SE Runtime Environment (build 1.8.0_212-b10)
Java HotSpot(TM) 64-Bit Server VM (build 25.212-b10, mixed mode)

# apt install openjdk-8-jdk

# apt purge ufw lxd lxd-client lxcfs lxc-common
# apt install iproute2 ntpdate tcpdump telnet traceroute nfs-kernel-server nfs-common lrzsz tree openssl libssl-dev libpcre3 libpcre3-dev zlib1g-dev ntpdate tcpdump telnet traceroute gcc openssh-server lrzsz tree openssl libssl-dev libpcre3 libpcre3-dev zlib1g-dev ntpdate tcpdump telnet traceroute iotop unzip zip

#cat /etc/security/limits.conf
#Root account resource soft limit and hard limit root soft core unlimited
root hard core unlimited
root soft nproc 1000000
root hard nproc 1000000
root soft nofile 1000000
root hard nofile 1000000
root soft memlock 32000
root hard memlock 32000
root soft msgqueue 8192000
root hard msgqueue 8192000
#Soft and hard resource limits for other accounts* soft core unlimited
* hard core unlimited
* soft nproc 1000000
* hard nproc 1000000
* soft nofile 1000000
* hard nofile 1000000
* soft memlock 32000
* hard memlock 32000
* soft msgqueue 8192000
* hard msgqueue 8192000

# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0
# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0
# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1
# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1
# Disable netfilter on bridges.
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0
# Controls the default maximum size of a mesage queue
kernel.msgmnb = 65536
# # Controls the maximum size of a message, in bytes
kernel.msgmax = 65536
# Controls the maximum shared segment size, in bytes
kernel.shmmax = 68719476736
# # Controls the maximum number of shared memory segments, in pages
kernel.shmall = 4294967296
# TCP kernel parameters
net.ipv4.tcp_mem = 786432 1048576 1572864
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_sack = 1
# socket buffer
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.netdev_max_backlog = 262144
net.core.somaxconn = 20480
net.core.optmem_max = 81920
# TCP conn
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_syn_retries = 3
net.ipv4.tcp_retries1 = 3
net.ipv4.tcp_retries2 = 15
# tcp conn reuse
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_tw_reuse = 0
net.ipv4.tcp_tw_recycle = 0
net.ipv4.tcp_fin_timeout = 1
net.ipv4.tcp_max_tw_buckets = 20000
net.ipv4.tcp_max_orphans = 3276800
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_syncookies = 1
#keepalive conn
net.ipv4.tcp_keepalive_time = 300
net.ipv4.tcp_keepalive_intvl = 30
net.ipv4.tcp_keepalive_probes = 3
net.ipv4.ip_local_port_range = 10001 65000
# swap
vm.overcommit_memory = 0
vm.swappiness = 10
#net.ipv4.conf.eth1.rp_filter = 0
#net.ipv4.conf.lo.arp_ignore = 1
#net.ipv4.conf.lo.arp_announce = 2
#net.ipv4.conf.all.arp_ignore = 1
#net.ipv4.conf.all.arp_announce = 2