Tag Archives: networking

EIGRP Route Filtering with ACLs

There are a number of reasons to implement route filtering. The filters can be used to control what routes are sent as well as what routes are learned from a neighbor. With ACLs the configuration is very flexible so just about anything is possible! Continue reading

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IPv6 Access List Basics

Chances are that if you have worked with IPv4 on the IOS platform for any length of time you are familiar with the access list formats, both standard and extended.  Assuming you know at least the basics of the addressing structure you should have no issue establishing similar ACLs for IPv6. Creating IPv6 ACLs The first considerations are that IPv6 ACLs have to be the “extended” format meaning the both the source and destinations have to be defined.  The ACLs also have to be named with a string as numbered ACLs are not acceptable.  The ACL name can contain numbers … Continue reading

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Cisco ASA IPSec Pre Shared Key Recovery

The Cisco ASA firewall is one of the most common firewalls I have encountered while both working in the corporate IT world as well as in the consulting industry with small to medium clients. Most administrators enjoy working with it as it has both a fairly intuitive interface in the form of the ASDM and a powerful CLI as well. One simple but common complaint, however, is that pre shared keys are difficult to recover from the units when working with IPsec tunnels. The solution is quite simple yet often elusive. Continue reading

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Cisco ASA Password Recovery

When inheriting used and abused customer networks it becomes necessary to reset passwords on devices the hard way from time to time. Fortunately with the Cisco ASA it’s still not all that complicated. You will see that with each step I included examples of the commands and the output along the way as well. Continue reading

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