Configuration Example, IP Telephony

Strange VPDN-GROUP behavior

René Jorissen on April 1, 2009 1 Comment • Tags: #group #l2tp #receive #receivewindow #tunnel #vpdn #vpdngroup

I noticed some strange behavior in a vpdn-group configuration on a Cisco 876 router. I have a router with the following vpdn-group configuration: vpdn-group pptp-group ! Default PPTP VPDN group description pptp vpn users accept-dialin protocol pptp virtual-template 10 The configuration is working perfectly and users can dialin using a PPTP connection. Backups of the … Read More

Configuration Example, Management

XMODEM recovery speed

René Jorissen on March 30, 2009 0 Comments • Tags: #115200 #3560 #3750 #9600 #baud #flash #rate #recovery #speed #tftp #xmodem

Configuring switches and routers is regular work for me. But if I would like to configure a switch or a router, I have to be able to boot the specific device…. Today I had to configure some new Cisco Catalyst 3650(E) en 3750 switches. In total I had 16 switches to configure, but three of … Read More

Configuration Example, Switching

Link State Tracking

René Jorissen on March 9, 2009 0 Comments • Tags: #based #blade #errdisabled #group #link #on #portid #route #state #system #tracking #virtual

Last week a friend called me and told me he was having serious problems with his network. A complete blade environment wasn’t able to communicate with the rest of the network. I asked what changed in the network and he told me that he had added a VLAN to a trunk allowed lists. Because he … Read More

Configuration Example, Routing

Policy NAT on Cisco router

René Jorissen on January 14, 2009 9 Comments • Tags: #address #based #cisco #dynamic #nat #network #policy #policybased #router #static #translation

A colleague of mine had to implement an IPSec VPN tunnel from a customer to a supplier. The customer has a Cisco router for connecting to the Internet, so nothing special. The router is already setup and in production. Configuring an extra IPSec VPN tunnel isn’t very hard, the most important part is the negotiation … Read More

Configuration Example, Security

Access rules DMZ components

René Jorissen on January 6, 2009 0 Comments

Finally he first post in 2009, so before starting, HAPPY NEW YEAR!!!!! I know it’s late, but who cares…. This post is about opening specific ports from the DMZ to the internal network. This specific topic often results in discussions about which ports to open. One of the biggest discussion points is the use of … Read More

Configuration Example, Routing

Netstat on IOS router

René Jorissen on December 4, 2008 0 Comments • Tags: #control #controlplane #host #netstat #openports #plane

I often use the netstat command on a Windows machine to check on which IP and/or ports the servers or workstation is listening or established connection. By accident I found the same kind of command for a Cisco IOS router, while I was looking through the CLI. Check out the output below: Router#sh control-plane host … Read More