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Cisco Features you should be using

I know more than once now the Cisco ISR/ISR-G2’s Series have been dubbed as the ‘Swiss Army Knife’ of networking devices, simply due to the amount of flexibility & the number of technologies available to you when deploying these devices. Luckily for us, these devices provide even more features available to us to assist with troubleshooting and maintaining the overall health of the network. What is even better is that many of these useful troubleshooting features exist on many of the other product families not just ISR/ISR-G2’s. I’ve had the pleasure to work on networks all around the world for some decent size companies so I wanted to kick off this list with what I consider to be the most useful tools built-in to Cisco devices that are not very well known out there.

1. Embedded Packet Capture (EPC) -- There is no doubt about it, but the ability to perform a packet capture at key points throughout the network can make troubleshooting particular issues that much easier. Luckily this feature exists on many different devices:

1. ISR G2′s -- Even the older ISR’s have this ability
2. ASA Firewalls
3. IOS-XE devices -- From the powerful ASR’s to the newer Catalyst 3850
4. NX-OS devices -- Granted on NX-OS you can capture packets that are process switched, there is an easy way around this by creating an Access-list to match the traffic you want to capture.
5. Even in Cisco UCS we can configure a traffic monitoring policy to capture traffic directly from particular servers and capture directly off the Fabric Interconnects. *This is more of a SPAN-type session than Embedded Packet Capture. Read More »

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Announcing the Cisco IOS Software Security Advisory Bundled Publication

Today, we released the final Cisco IOS Software Security Advisory Bundled Publication of 2014. Six years ago, Cisco committed to disclosing IOS vulnerabilities on a predictable schedule (on the fourth Wednesday of March and September each calendar year) in direct response to your feedback. We know this timeline allows your organization to plan and help ensure resources are available to analyze, test, and remediate vulnerabilities in your environments.

Today’s edition of the Cisco IOS Software Security Advisory Bundled Publication includes six advisories that affect the following technologies:

  • Resource Reservation Protocol (RSVP)
  • Metadata
  • Multicast Domain Name System (mDNS)
  • Session Initiation Protocol (SIP)
  • DHCP version 6 (DHCPv6)
  • Network Address Translation (NAT)

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A Bundle is Born

Today, we released the first Cisco IOS Software Security Advisory Bundled Publication of 2014. Six years ago, Cisco committed to disclosing IOS vulnerabilities on a predictable schedule (on the fourth Wednesday of March and September each calendar year) in direct response to your feedback. We know this timeline allows your organization to plan ahead and ensure resources are available to analyze, test, and remediate vulnerabilities in your environments.

Today’s edition of the Cisco IOS Software Security Advisory Bundled Publication includes six advisories that affect the following technologies:

  • Session Initiation Protocol
  • Network Address Translation
  • Internet Key Exchange Version 2
  • IPv6
  • SSL VPN
  • Cisco 7600 RSP720 with 10GE Uplinks

Read More »

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It’s Back – It’s Cisco IOS Software Security Advisory Bundle Time Again

Today, we released the final Cisco IOS Software Security Advisory Bundled Publication of 2013. We committed to these predictable disclosures back in 2008 because your feedback was clear—they allow you to plan ahead and ensure resources are available to analyze, test, and remediate vulnerabilities in your environments. (For more information on the history of this evolution, take a look at my colleague John Stuppi’s post this past March.) If you haven’t had the opportunity to review my earlier posts on preparing for bundled disclosures or leveraging the Cisco IOS Software Checker tool, I’d encourage you to do so now. Hopefully, the guidance will help lessen the impact of evaluating the recently published Cisco Security Advisories. Read More »

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Offline Analysis of IOS Image Integrity

Forensic analysis of IOS images can be a tricky science, due in part to the diversity in IOS image versions and branches. Between IOS 11 and IOS 12.4, over five thousand different images were built, a quarter of which belong to the 12.2 train. Some IOS trains are in more widespread use than others, just as some hardware platforms are more popular than others, but even when narrowing down by feature-set or hardware, there is a large diversity of images. There are however, some steps that can be taken, both while the IOS device is running, as well as offline, that can help determine the integrity of an IOS image.

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