I’ve already written about Linux static routing configuration. However, sometime you need to configure Linux routers dynamically to get changes of network connections by communicating information about which networks each router can reach and how far away those networks are. These days most network admin prefer to use OSPF or BGP over RIP. Linux and UNIX system can act as router using special software.
Quagga is a network routing suite providing implementations of OSPF (v2 & v3), RIP (v1, v2 & v3) and BGP (v4) for Unix-like platforms, particularly FreeBSD, Linux, Solaris and NetBSD. Quagga is a fork of GNU Zebra. Quagga is intended to be used as a Route Server and a Route Reflector. It is not a toolkit, it provides full routing power under a new architecture.
Zebra IP Routing Manager
zebra is an IP routing manager. It provides kernel routing table updates, interface lookups, and redistribution of routes between different routing protocols. zebra is included with quagga software.
Debian / Ubuntu Linux user type the following command:
$ sudo apt-get install quagga
RHEL , Fedora, CentOS Linux user type the following command:
# yum install quagga
quagga Software Configuration
quagga configuration is beyond the scope of this blog post; I recommend reading official configuration documentation for further information.
Explains how to configure ip aliasing under Ubuntu Linux operating system so that you can have multiple IP address assigned to a single interface.
I am getting error that read as No Route to Host. I am trying to ping my ISP gateway as well as DNS server but I am getting this error. How do I solve this problem?
This problem indicate networking conflicts or some sort of networking configuration problem.
Here are things to check:
Can you ping to your local router interface (such as 192.168.1.254)?
Make sure your card (eth0) is properly configured with correct IP address and router address. Use ifconfig command to configure IP address and route command to setup correct router address. If you prefer to use GUI tools:
- redhat-config-network – Works on Red Hat and Fedora Linux/Cent OS.
- network-admin – Debian and Other Linux distribution use this GUI too
Use above two GUI tools to setup correct IP address, DNS address and router address.
b) Make sure firewall is not blocking your access
iptables is default firewall on Linux. Run following command to see what iptables rules are setup:
# /sbin/iptables -L -n
You can temporary clear all iptables rules so that you can troubleshoot problem. If you are using Red Hat or Fedora Linux type command:
# /etc/init.d/iptables save
# /etc/init.d/iptables stop
If you are using other Linux distribution type following commands:
# iptables -F
# iptables -X
# iptables -t nat -F
# iptables -t nat -X
# iptables -t mangle -F
# iptables -t mangle -X
c) Finally make sure you are using a router and not a proxy server. Proxy servers are good for Internet browsing but not for other work such as ftp, sending ICMP request and so on.