Cisco has weird naming conventions for groups of interfaces

If you want to bind some ethernet interfaces into one logical interface between two ciscos switches you have to configure an interface first: interface Port-channel 1 then add some interfaces into this new interface: interface GigabitEthernet 1/0/1         channel-group 1 mode active and you can check the status with: show etherchannel 1 summary Three names …

Continue reading ‘Cisco has weird naming conventions for groups of interfaces’ »

L2TP tunnel between two cisco routers

Problem: a Cisco 1941 [15.1(2)T2] (Client) tries to connect to an Cisco7300 [12.3(22)] (Server) using L2TP, but after successful authentication of the client the server drops the connection. Solution: The client tried to authenticate the server, but the server had no password for authentication. Normally only the client authenticates to the server in ISP environments. …

Continue reading ‘L2TP tunnel between two cisco routers’ »

Cisco Access Point blocking PPTP

Vienna: 10. August 2011 Problem: A network of some Cisco Access Points AIR-AP1142N-E-K9 connected to an small router works good as expected but when the user tries to connect to en PPTP VPN the connection fails with a time-out. Solution: it was no NAT problem in this case (I fixed this before). Cisco IOS 12.4(21)?? …

Continue reading ‘Cisco Access Point blocking PPTP’ »