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2018

  • 4 min read

Barracuda Load Balancer - Powershell

Working on my Powershell skills, I was playing around with a Barracuda Load Balancer and noticed it supported some APIs which is kind of cool. At first I was playing around with it in postman and got to login and put some servers in maintenance mode, but then thought it would be really neat if I could get this working in Powershell, that way us humans can just run a script and even thinking in the "future" maybe have some automated process (a.k.a AI) handle this for us. ;) So in this post I'll talk about the script I created and some of the small challenges I had with this overall it was kind of neat putting this together. TLDR: Here is the script if you don't want to read:

  • 3 min read

Automation Dance

I keep doing the automation dance, (yeah...that's me) there are a lot of different tooling products out there. I have been trying to understand a use case around using it with network automation. Recently I have been dancing around with Ansible. My personal belief is that using any type of these tools would be helpful but it can be a steep learning curve if you really don't have any programming knowledge. This is not something that is relatively easy to use or understand, don't expect to have a working network automated tool in production on day one. I think this is great for learning, and using this in a network sandbox. If you don't have programming mindset it might make your job harder on day one before it gets easier, but just like learning to dance you have to learn the steps, the moves, and maintain the rhythm. So with that let's at least figure out the starting points, and begin learning the steps of the automation dance. ;)

  • 3 min read

Enable a RESTful ASA API

Starting from ASA 9.3(2) and onward the 5500-X hardware supports a RESTful API as an additional method for configuration/monitoring ASA hardware. Infrastructure as code as they call it, not anything new but I was reading a post that Ivan Pepelnjak wrote and as he points out there are two types of styles when we are dealing with IaC, the data model or CRUD. When reading information about the ASA RESTful API it was interesting what the ASA falls into, CRUD is the method it uses and although this method works, I have similar feeling to what Ivan posted, it wonders me if this is really a step forward into IaC. In this post we'll go through the steps to enable it and you can be the judge, does this RESTful API help?

  • 3 min read

Verifying DNS Lists - FMC

We are back with another post about Cisco's Firepower Management Center and this time we are working with the DNS list which if you have a protect license you can have your Firepower modules or your FTD (Firepower Threat Defense) devices look at DNS requests and deny the requests if they are malicious. These have to be applied on your access control policy to be able to use it and in this post we are going verify some of the domain names that are in this lists.

  • 5 min read

Installing a GNS3 Server

Although GNS3 can run local on your computer and you can use VMware Workstation and have the GNS3 appliance. I found it much more stable and predictable to run GNS3 on a dedicated server. Using this type of installation, all the projects, and images are stored on the GNS3 server, so I can install the GNS3 client any computer and get access to the same projects I was working on. You can also have multiple people working on different projects that are on the same server. I find that neat for educational use or if you where helping someone with a project. In this post I’ll walk though the steps needed to set up a GNS3 server.

  • 4 min read

Cisco FTD Standalone

No management centers here, sometimes a standalone firewall is all you need. In this post I have a FTD appliance and there really isn’t a need tie this into Cisco’s Firepower Management Center. So we’ll configure appliance in standalone mode and go through the initial first steps that are required to get it online and walk through Firepower Device Manager. If you worked with Cisco FMC you’ll find its pretty similar, so with introductions out-of-the-way let’s get started!

  • 8 min read

Too Many TCP Resets

So, recently we enforced some firewall rules on a new environment, we did testing of the environment and everything was working as expected. In about 24 hours a lot of traffic from the web infrastructure was being denied and it continued, at first glance it looked like return traffic was being dropped, the web servers were sourcing at port 443 and the destination ports were using dynamic ports (RFC 6335) No user or application problems were reported when we enforced rules, and we waited additional days to see if anything came up. Nothing came up, the only thing was a spike in amount of syslog messages of dropped traffic coming from the web servers.

  • 3 min read

Configuring Layer Three EtherChannel

When you want more speed all you need is EtherChannel, EtherChannel can be configured as a layer three logical interface instead of just sitting at layer two. This is very helpful if we are running layer three down to the access layer switches, instead of at the distribution layer. You also could see this in a collapsed core design, we also don’t have to worry too much about STP when we configure EtherChannel’s. The only requirements to use layer three EtherChannels is your switch need is support layer three “routed” interfaces, so with that let's get started!

  • 3 min read

Wireless VLANs

It’s been fun four months of 2018 so far and I’m back to talk about Wireless VLANs. With 802.11ax around the corner (2019) I think we all can agree that “weird” connections although less likely have interference isn’t as mobile as a wireless LAN. Also, with 802.11ax the maximum theoretical throughput is 10Gbps! We’re going to need some serious backend infrastructure available to be able to support that type of bandwidth. So, let’s look at configuring a wireless VLANs for our mobile users!

  • 5 min read

Private VLANs

Let's start out 2018 with private VLANs, with PVLANs the network gets a little more privacy added to it. When we have privacy on the network we can seclude certain parts of it. Essentially, "you can go about your business - move along, move along". Private VLANs allow us to segment networks within a single VLAN. So in this post we'll go over the types of PVLANs as well as setup a network topology with private VLANs, Let's get started!