Configuration Example, Routing

Cisco DHCP server & VRF

René Jorissen on December 12, 2012 4 Comments • Tags: #cisco #class #connected #dhcp #excluded-address #exclusion #ios #server #use #vrf

I had some issues while configuring some VRF’s on a Cisco router and using that router as a DHCP server. First of all the router wasn’t binding any DHCP request. The DHCP server configuration is defined below. ip dhcp pool guest vrf vrf-guest network 10.10.0.0 255.255.252.0 default-router 10.10.0.1 domain-name internet-only.nl dns-server 208.67.222.222 208.67.220.222 The configuration … Read More

Configuration Example, Firewalling, Routing

NBAR and smart filtering

René Jorissen on February 15, 2011 2 Comments • Tags: #application #based #http #match #mime #nbar #network #protocol #recognition

NBAR (Network Based Application Recognition) is a cool Cisco tool to identify and classify content flowing through a router. You can identify applications as mission critical, business-related, non-critical or unwanted. Once these mission critical applications are classified they can be guaranteed a minimum amount of bandwidth, policy routed, and marked for preferential treatment. Non-critical applications … Read More

Routing

XS4ALL, Cisco 877 and IPv6

René Jorissen on February 1, 2011 1 Comment • Tags: #advertisements #autoconfiguration #bvi #cscej5092 #delegation #dhcpv6 #general-prefix #ipv6 #other-config-flag #prefix #router #routing

A while ago my ISP XS4ALL started with the distribution of IPv6 prefixes to their customers. So as a network engineer I wanted to have my own /48 prefix. Sadly I didn’t had time to start testing at the beginning of the IPv6 “launch”. Last week I found some time to start my testing. I … Read More

Configuration Example, Routing

Policy-based routing in a nutshell

René Jorissen on October 13, 2010 1 Comment • Tags: #based #c #cisco #pbr #policy #routing

Lately I received some questions about routing decisions and how to influence the routing decisions via access control lists. The following example shows a simple configuration for policy-based routing. The example uses the following logical setup: I configured two routers and connected each router to two PVC’s on the same ATM interface. I configured one … Read More

Routing

ISDN Backup – still alive?

René Jorissen on May 26, 2010 3 Comments • Tags: #backup #eigrp #floating #isdn #ospf

Nowadays everybody wants redundancy within their network, especially when using remote sites. Customers are using multiple ISP’s for redundancy and/or configure BGP solutions. In the old days (hear me talking with my 27 years) ISDN was often used for backup purposes and I still use it sometimes as redundancy mechanism. Everybody knows that bandwidth is … Read More

Routing

Huh? Interface SSLVPN-VIF0?

René Jorissen on March 8, 2010 0 Comments • Tags: #interface #sslvpn #sslvpn-vif #vif

While checking interface statistics on a Cisco 3845, I noticed the following layer 3 interfaces. Interface                  IP-Address      OK? Method Status                Protocol GigabitEthernet0/0         74.124.155.67   YES NVRAM  up                    up GigabitEthernet0/1         10.10.10.1      YES NVRAM  up                    up GigabitEthernet0/0/0       unassigned      YES NVRAM  administratively down down SSLVPN-VIF0                unassigned      NO  unset  up                    up Tunnel0                    192.168.255.2   YES NVRAM  up                    up I can explain … Read More