In the above topology I have auto-summary enabled on R1 and R2. R3 does not have auto-summary. The result of this config is R1 and R2 will actually advertise the 10.0.0.0/8 network, since both of those 10. networks reside in that classful boundary. Since their only neighbor is R3, R3 will have a duplicate route …
Moving DHCP from Server to Server with Powershell
My scenario: I needed to move DHCP from server 2012 to server 2012 R2 with leases. I wanted to do this quickly and safely. You can run all of these commands from your new DHCP server: Install DHCP + MGMT tools on the new server. Install-windowsfeature DHCP -includemanagementtools Authorize the new server Add-DhcpServerInDC Backup the …
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So true
Basic Prevention of Rouge DHCP Servers with DHCP Snooping
What problem are we trying to solve? We want to prevent the rouge DHCP Server from assinging addresses out to our clients. Normally this would be your favorite wanna-be IT employee that brings his own Linksys router in the mix to fix the network 🙂 Of course it can also protect from malicious …
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IPv6 Static Tunnel Over IPv4 Infrastructure
The problem : What if we want to speak IPv6 but the whole path isn't IPv6? Here is our topology let's begin. IOSv1 and 2 are dual stacked, however the link between IOSv1 and IOSv2 is not IPv6. This link represents many routers. There's always a chance that they don't support IPv6 …
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Understand Prefix-List Logic With Examples
Prefix-lists are typically used by router "features" to provide filtering. They "pass" permitted networks to a filtering feature which will actually do the filtering. They are used by distribute-lists, filter-lists, route-maps. Basics Some quick points which will guide you on understanding the basics. IP prefix list can match on sub netmask of route (ranges). They …
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