linux

linux.md

Network

Obsolete command

• ifconfig => ip addr and ip link
• netstat => ss, ip route

Set interface up on boot

/etc/sysconfig/network

NETWORKING=yes

/etc/sysconfig/network-scripts/ifcfg-XXX

DEVICE=XXX
BOOTPROTO=dhcp
ONBOOT=yes

Red Hat

# GRUB default option
grub2-set-default <option #>

# Set host name for current session
hostname <name>

# Set host name permanently
hostnamectl set-hostname <name>

# Network config
vi /etc/sysconfig/network
# Red Hat 6
system-config-network
# Red Hat 7
nmtui

# Network restart
service network restart
systemctl restart network.service

# Test DNS server (IP: 8.8.8.8)
dig @8.8.8.8 www.google.com

# Allow incoming DNS
iptables -I INPUT -p udp --dport 53 -j ACCEPT
iptables -I INPUT -p tcp --dport 53 -j ACCEPT

# RPM install
rpm -i <package>
rpm -ivh <package>

# RPM remove
rpm -e <package>

# RPM list
rpm -qa

# YUM
yum install <package>
yum search <keyword>
yum remove <package>
yum update

IP forwarding and NAT

DHCP server

Setup

DNS server

Setup

Setup Split

Chinese Info

Sync DHCP master-slave zone file rndc reload

Firewall

• Reference (Red Hat)
• Reference (Oracle Base)
• Reference (Bromosapien)

Firewall IP forwarding and NAT

firewall-cmd --change-interface=enp0s1 --zone=external --permanent
firewall-cmd --change-interface=enp0s2 --zone=internal --permanent 
firewall-cmd --set-default-zone=internal
firewall-cmd --complete-reload

Firewall add service

Allow DNS for public zone

firewall-cmd --zone=public --add-service=dns

Debian

dpkg

# Install package
dpkg -i *.deb
dpkg --install *.deb

# Remove package except conf files
dpkg -r <package>
dpkg --remove <package>

# Remove package and conf files
dpkg -P <package>
dpkg --purge <package>

# List installed package
dpkg --get-selections

# List all package
dpkg --list

apt

apt-get install <package>
apt-get remove <package>
apt-get update
apt-cache search <keyword>

Create local yum repo

Reference

# Install createrepo, you may need to install dependencies
rpm -ivh createrepo-X.X.X.rpm
# change to the rpm folder
cd /media/cdrom/Packages
createrepo .

Create repo config /etc/yum.repos.d/local.repo, and disable other repo by using enabled=0

[local]
name=Linux Local Packages
baseurl=file:///media/cdrom/Packages
enabled=1
gpgcheck=0
protect=1

Check repo config

yum repolist