MPLS LDPD LINUX EXPERIMENT(Quagga)

本文为原创，禁止转载。 文章是在个人研究怎么在LINUX上实现MPLS的总结。暂时LINUX上还没法实现BGP MPLS VPN

1.Build a linux environment supporting mpls ,quagga and ldpd

建立MPLS在linux上转发基础环境的步骤

1) upgrade kernel

It need linux kernel support mpls stack.Such kernel 4.6 需要linux内核支持mpls模块，更新内核

wget wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.6-yakkety/linux-headers-4.6.0-040600_4.6.0-040600.201606100558_all.deb wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.6-yakkety/linux-headers-4.6.0-040600-generic_4.6.0-040600.201606100558_amd64.deb wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.6-yakkety/linux-image-4.6.0-040600-generic_4.6.0-040600.201606100558_amd64.deb

install dpkg -i *.deb

update grub and reboot update-grub reboot

2) Enable MPLS in kernel

调整MPLS内核参数，启用MPLS stack

modprobe mpls_router modprobe mpls_gso modprobe mpls_iptunnel sysctl -w net.mpls.conf.eth0.input=1 sysctl -w net.mpls.conf.lo.input=1 sysctl -w net.mpls.platform_labels=1048575

You’ll need to set net.mpls.conf.[interface-name].input=1 for any other interfaces that you plan to receive MPLS packets on, otherwise the MPLS route table won’t accept your routes

3) Install quagga-ldp

安装quagga-ldpd，需要源码编译，因为直接的发行版本默认没有ldpd

git clone git clone https://github.com/rwestphal/quagga-ldpd.gitapt-get apt-get install autoconf automake texinfo libtoolcreate Makefile cd quagga-ldpd ./bootstrap.sh #autoreconf -i./configure ./configure --enable-tcp-zebra --enable-mpls --enable-ldpd --sysconfdir=/etc/quagga --localstatedir=/var/runmake & make install make make installldconfig ldconfig /usr/local/lib

ERROR: 1. AWK \1 Error apt-get install gawk 2. configure: error: vtysh needs libreadline but was not found and usable on your system. apt-get install libreadline-dev

4) Start quagga

启动quagga，需手动建pid文件，已邮件联系开发者

user useradd quaggaset permission chown -R quagga.quagga /etc/quaggacreate pid information touch /var/run/zebra.pid chmod 755 /var/run/zebra.pid chown quagga.quagga /var/run/zebra.pid

touch /var/run/ospfd.pid chmod 755 /var/run/ospfd.pid chown quagga.quagga /var/run/ospfd.pid

touch /var/run/ldpd.pid chmod 755 /var/run/ldpd.pid chown quagga.quagga /var/run/ldpd.pid

create ldpd vty file touch /var/run/ldpd.vty chmod 755 /var/run/ldpd.vty chown quagga.quagga /var/run/ldpd.vty chmod 777 /var/run

config

安装完会有默认配置，直接最简单的配置用于启动即可 cp /etc/quagga/zebra.conf.sample /etc/quagga/zebra.conf cp /etc/quagga/ldpd.conf.sample /etc/quagga/ldpd.conf

start zebra -d -f /etc/quagga/zebra.conf ospfd -d -f /etc/quagga/ospfd.conf ldpd -d -f /etc/quagga/ldpd.conf

ldpd experiment

基础环境已经完成，正式实验开始

environment 环境

10.63.26.1x is Debian Linux IP for ssh to manage.And 4.4.4.4 / 9.9.9.9 / 6.6.6.6 is loopback IP for experiment.

10.63.26.x网段是用于管理的ssh网段。而4.4.4.4等IP是用于测试MPLS流量。

We can make it through such command: 通过以下命令创建lo1 ip link add name lo1 type dummy ip link set dev lo1 up ip addr add 4.4.4.4/32 dev lo1

set static route 设置静态路由

we need to create a step by step environment ,so that we can catch the mpls tag changement .Rather than a next hop tag “3”.

用于建立一跳到一跳的情景，原因是机器同在一网段，如果使用OSPF协议，IP地址均为下一跳，MPLS的标签只会是3（即没MPLS标签, pop）

In 10.63.26.14 , config in zebra through : ip route 6.6.6.6/32 10.63.26.19 ip route 9.9.9.9/32 10.63.26.19

10.63.26.19: ip route 6.6.6.6/32 10.63.26.16 ip route 4.4.4.4/32 10.63.26.14

And 10.63.26.19: ip route 9.9.9.9/32 10.63.26.19 ip route 4.4.4.4/32 10.63.26.19

Now, every Linux can reach the others loopback IP step by step.

Config ldpd 配置ldpd

以下为不同机器ldpd中关键的配置，用于建立ldpd邻居，传递标签

In 10.63.26.14 config…

mpls ldp router-id 4.4.4.4 dual-stack transport-connection prefer ipv4 dual-stack cisco-interop neighbor 9.9.9.9 password testmpls ! address-family ipv4 discovery transport-address 4.4.4.4 ! interface eth0 ! ! !

In 10.63.26.19 config…

mpls ldp router-id 9.9.9.9 dual-stack transport-connection prefer ipv4 dual-stack cisco-interop neighbor 4.4.4.4 password testmpls neighbor 6.6.6.6 password testmpls ! address-family ipv4 discovery transport-address 9.9.9.9 ! interface eth0 ! ! !

In 10.63.26.16 config…

mpls ldp router-id 6.6.6.6 dual-stack transport-connection prefer ipv4 dual-stack cisco-interop neighbor 9.9.9.9 password testmpls ! address-family ipv4 discovery transport-address 6.6.6.6 ! interface eth0 ! ! !

After that,we can show mpls ldp neighbor

Test 测试

从14机器用4.4.4.4ping6.6.6.6 In 10.63.26.14: ping -I 4.4.4.4 6.6.6.6

And we can catch packet in 10.63.26.19: tcpdump -ni eth0 mpls and icmp 通过在中间跳机器tcpdump抓取mpls的包

Done!