DHCP Reservation on Cisco Router or Layer 3 Switch

12. September 2016 Cisco Router, Cisco Switch 3,105
If you are handing out DHCP via your router and layer 3 switch, here’s how to add a DHCP reservation to the mix.  I’m including the entire DHCP configuration.  The reservation section is noted below.   ip dhcp excluded-address 10.251.0.1 10.251.0.99 ip dhcp pool DATA network 10.251.0.0 255.255.255.0 domain-name mydomain.local default-router 10.251.0.1 dns-server 10.251.0.5 lease ...

Cisco Router Reverse Telnet

28. September 2015 Cisco Router 5,757
If you connect the router’s aux port to another device’s console port, you can telnet to the router using reverse telnet to connect to the other device’s console via your aux port. Here’s how to set it up. Connect your router’s aux port to another device’s console port using a Cisco flat crossover cable, or basically ...

Block an IP from accessing the network on a Cisco Router

30. January 2014 Cisco Router 2,547
We had a client call and say their site was being hammered. Through Cisco’s IP Accounting, we discovered a device on the network getting whacked by a ton of IP Addresses from the Internet.  I gave them the IP to investigate but with DHCP they had no way to tell who it was.  So we slapped on a quick ACL ...

Cisco Router Reload Kron Job

21. January 2014 Cisco Router 2,700
I read once and awhile users wanting to reload their routers automatically.  Not exactly sure why someone would need to reload the router.  But I’ve recently come across using some old docs using ‘kron’.  I used something similar to reset some voice ports that would hang offline during some troubleshooting.  I don’t know much about ...