Network technology-IPv6 applications for Linux networks (1)

Article title: Network Technology-IPv6 applications for Linux networks (1 ). Linux is a technology channel of the IT lab in China. Includes basic categories such as desktop applications, Linux system management, kernel research, embedded systems, and open source.
Internet Protocol Version 6 is a next-generation network Protocol that replaces IPv4. it has many new features and functions. As a next-generation Internet Protocol, IPv6, which was generated and developed by the IP address crisis, has been recognized by all parties. in the future, the development of the Internet cannot be separated from IPv6 support and application. The Ipv6 and Ipv4 protocols are not similar in terms of structure or system tools. Linux supports IPv6 in all operating systems first. here we will introduce the IPv6 address, route settings, firewall configuration, and security tools in Linux, this allows you to quickly transition from IPv4 to IPv6 in a Linux network environment.
　　
　　 Configure Ipv6 protocol
The following describes how to deploy IPv6 in Linux using the example of Mandrake 9.1 Linux.
　　
1. load the IPv6 module
　　
Compared with Windows systems, Linux provides better Ipv6 support. generally, Ipv6 can be used directly in Linux versions based on the 2.4 Kernel. before using IPv6, check whether the system's Ipv6 module is loaded, if you do not have one, you can use the command to manually load it. This requires the permissions of the Super User. Then run the command to check that the IPv6 address (inet6 addr: fe80: 200: e8ff: fea0: 2586/64) is displayed on the fifth line to verify that IPv6 has been loaded.
　　
# Modprobe IPv6
　　
# Ifconfig-
　　
The following content is displayed:
　　 　
　　 IPv6 address loaded
　　
2. use the Ping command to check whether the IPv6 address of the NIC is valid.
　　
Unlike IPv4, you must specify a Nic Interface when using the Ping6 command. Otherwise, the system will not know which network device to send data packets to. I indicates that Interface, eth0 is the first Nic, and c indicates the loop, 3 indicates three Ping6 operations. The results are as follows:
　　
# Ping6-I eth0-c 1 fe80 :: 200: e8ff: fea0: 2586
　　
3. use IP commands
　　
The IP command is a powerful network configuration tool in the iproute2 software package. it can replace some traditional network management tools. For example, ifconfig and route.
　　
(1) use the "ip" command to view the IPv6 route table:
　　
#/Sbin/ip-6 route show dev eth0
　　
(2) use the "IP" command to add a route table:
　　
#/Sbin/route-A inet6 add 2000:/3 gw 3ffe: ffff: 0: f101: 1
　　
(3) use the IP command to set the multi-point propagation Neighbor Solicitation of IPv6
　　
The IPv6 Neighbor disbor inherits IPv4's ARP (Address Resolution Protocol). you can obtain information about network neighbors again and edit/delete it. you can use the IP command to know the network neighbor settings (where, 00: 01: 24: 45: 67: 89 is the MAC address of the data link layer of the network device ):
　　
# Ip-6 neigh show fe80: 201: 23ff: fe45: 6789 dev eth0 ll addr 00: 01: 24: 45: 67: 89
　　
Router nud reachable
　　
　　 Firewall for Linux Ipv6 network environment
Installation:
　　
The key to firewall based on Linux2.4 kernel is iptables. In the 2.2 series, it replaces ipchains and ipfwadm before the 2.0 series. If you want to use any form of firewall, you need to install iptables.
　　
(1) Download the Ipv6 version of iptables, Download link: ftp://ftp.uni-bayreuth.de/pub/linux/arklinux/1.0-0.alpha8.2/i586/iptables-ipv6-1.2.7a-1ark.i586.rpm
　　
(2) install the firewall:
　　
# Rpm-ivh iptables-ipv6-1.2.7a-1ark.i586.rpm
　　
Configure iptables
　　
Iptables is an IP information packet filtering system integrated with the mainstream Linux kernel version 2.4.x. If the Linux system is connected to the Internet or LAN, server, or a proxy server connected to the LAN and Internet, the system facilitates better control of IP packet filtering and firewall configuration on the Linux system. The netfilter/iptables IP information packet filtering system is a powerful tool that can be used to add, edit, and remove rules. these rules are used for filtering and determining information packets, rules of the firewall. These rules are stored in a dedicated information packet filtering table, which is integrated into the Linux kernel. In the information packet filtering table, rules are grouped in a chain. The following describes these rules and how to create them and group them in the chain.