Tag Archives: Cisco ASA

Cisco ASA Troubleshoot IKE Policy

Notes for troubleshooting Cisco ASA IKE Policy – there must be a match between site-to-site / lan-to-lan (L2L) endpoint IPSec Peers for the ISAKMP (IKE) session to be established. Traditionally this was known of IPSec Phase One, but as of … Continue reading

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Cisco ASA Command Line Basics

This post is for people who are new to the Cisco ASA command line, or seasoned network administrators like myself who need to review or brush up on the command line basics for the ASA console. Instead of using my … Continue reading

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AES-GCM on Cisco ASA

This is a request for comments to clarify network security proper usage of new AES-GCM cryptography functionality on the Cisco ASA platform. Please leave a comment if you can provide some insight to help readers better informed on how and … Continue reading

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Policy Based Routing on Cisco ASA

One feature I’ve been wanting on the Cisco ASA has finally been added in software release 9.4.x, Policy Based Routing (PBR). This allows traffic to be sent to different ISP connections based on your desired match criteria (specific source network, … Continue reading

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Cisco ASA ARP Behavior

The Cisco ASA can exhibit some non-standard ARP behavior depending on the OS version and system configuration. Here are some notes to remember this by. arp permit-nonconnected – command introduced in ASA 8.4(5) and defaults to off. ASA releases through … Continue reading

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IKEv2 Cisco ASA Single Peer Limit

Cisco has been hard at work bringing IKEv2 support to the ASA firewall, but the feature set still lacks an important item currently only available using IKEv1 on the ASA. This feature is “Multiple peers used for redundancy” and is … Continue reading

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DHCP Server on Cisco ASA

The Cisco ASA firewall provides basic DHCP Server functionality. If you’re running a Windows Active Directory Domain, I recommend you use the Microsoft DHCP server. For testing purposes, the ASA built-in DHCP server can be useful. If you enable a … Continue reading

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Cisco ASA Default SSL Broken

Just a note that out of the box, recent Cisco ASA hardware with new ASA software releases ships with broken SSL. This prevents the ASDM GUI (Advanced Security Device Manager) from functioning. To correct the problem, you must force the … Continue reading

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Recent IPv6 Updates for Cisco ASA

Cisco is constantly updating the software for their ASA firewall product line. Recent features in 9.x provide more full-featured support for native IPv6 features. Here are some brief highlights: Cisco ASA 9.x – AnyConnect VPN Client over SSL (IPv6 client … Continue reading

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Cisco ASA QOS

It may be desirable to rate-limit traffic to various hosts or subnets on your network. The Cisco ASA has some very limited QOS capabilities built in (better QOS features are available on Cisco IOS routers). To apply a basic rate … Continue reading

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