Category Archives: Networking

Cisco, HP ProCurve, firewalls, routers, switches, wireless access points, etc.

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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Get Rid of virbr0

In RHEL 7.x and CentOS 7.x you may see an odd extra network interface listed as “virbr0” (virtual bridge zero). This is provided as a default way to share the host physical network with private guest virtual machines. Unfortunately this … Continue reading

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IPv6 Users and Devices

There is good news for IPv6 as the future protocol of the Internet. It has been a long and rough road, but people are finally beginning to use NATIVE IPv6 to access web services. The funny thing is that the … Continue reading

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Windows DHCP Failover Load Balancing

Windows Server 2012 (and newer) provide a powerful option for DHCP service high availability. You configure a DHCP scope on one server and then configure “Failover Load Balancing” to replicate the scope to the partner DHCP server. This new DHCP … Continue reading

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Broadcom QLogic VMQ Hyper-V Network Bug

UPDATE August 2017, following this issue as it’s in my top 10 most viewed posts. User @StephanF over on forums.veeam.com reports that the issue persists with newer 10G Broadcom/QLogic NIC’s. “Updates of drivers, NIC firmware etc. did not help … … 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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ARP Timeout in Cisco IOS

If you’re managing Cisco IOS routers, you might want to adjust the settings for ARP cache timeout. The default value is 4 hours which can be a long time to wait if you are changing out hardware and using the … Continue reading

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Cisco Integrated Service Router QOS with Switch Module

The Cisco Integrated Service Router (ISR) product line has the option to include switch ports using either a fixed-port configuration on low-end models, or switch modules on higher-end ISR routers. The newer second generation (G2) routers support gigabit switch ports. … Continue reading

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Intel PROSet Wireless Compatibility with Cisco VPN

I’ve noticed a frequent compatibility problem with the classic Cisco VPN client (IPSec IKEv1) in combination with certain Windows network drivers. In particular, the Intel PROSet software wreaks havoc with the Cisco VPN Client name lookup capabilities (DNS over Tunnel). … Continue reading

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