When you see an hacker movie you see people typing on the keyboard very fast. Actually the toughest the hacker is the faster he types very long commands and all of them work the first time. Want to impress friends…
IP addressing design is a topic that follows every networker from the basic to the architect level of experience. Usually we just pick a random range from RFC1918 and address all the devices. But then VPN happens, and with VPN…
Platform: CISCO2921 IOS version: 15.3(3)M5 Load the anyconnect package on the flash of the router and configure anyconnect client package: crypto vpn anyconnect flash0:/webvpn/anyconnect-win-4.1.04011-k9.pkg sequence 1 Create a virtual template, that’s the interface the VPN clients will attach to: interface…
As a holder of many technical certifications every few months I have to renew some. When possible I try to renew the certifications with a new track instead of doing the newer version of the exam I’ve already done. This…
SecureCRT is one of my favourite tools, today I had a chance to use it in a way I didn’t expected. A customer called with a problem: he has a radio bridge that sometimes loses connection with the remote unit.…
This post is part of a series about Docker, including: Docker Introduction Docker: Install software inside a container Docker Volumes Docker Networking – bridge container to host NIC We started with the basics and moved on with adding software, using…
This post is part of a series about Docker, including: Docker Introduction Docker: Install software inside a container Docker Volumes Today we’ll see Docker networking with a very specific target in mind: bridge container to the host network. This isn’t…
Docker Volumes In the last post we saw that any filesystem change inside a docker container is lost if not commited to the image. What if we want to share data between containers? We can use Docker’s Data Volumes and…
In the first post of this series we left with a running Ubuntu 15.04 container. Now it’s time to install software inside the container. A container is “stateless”, meaning any file change inside a container is lost when the container…
Docker and more generic Linux containers technology are a hot topic these days. The website says “for developers and sysadmins”, I am neither of the two but I can still find some useful applications for containers as a Network Engineer.…
I work as a consultant for many clients, often jumping from different networks. Management networks sometimes don’t have a DHCP server, in some networks I have a special IP address assigned to access some devices, in other networks I need…
Quick tool: PingInfoView PingInfoView is a small utility that allows you to easily ping multiple host names and IP addresses, and watch the result in one table. It automatically ping to all hosts every number of seconds that you specify,…
A quick batch script I did to backup configuration files of multiple Alcatel Omniswitch via FTP. All files are named boot.cfg so the script renames each file appending the IP address. Create a file with all the IP of switches…
Today I’ve attended a Meraki technical training course at Cisco offices. The training was organized in short presentations of product features followed by hands-on labs based on all the products available today. I was suprised to find not only people…
I had a Raspebby Pi sitting on my desk for a while. I used it as a media center, low-power Linux server, NAS, serial console server but it eventually was replaced by other hardware and software and became just another…
Just a quick post since I speak with many network engineers and I notice some confusion about this topic. Are all 4 pairs of an Cat5e cable used? The answer is.. it depends. For gigabit speed 1000T all four pairs…
This week I attended a two days training of Cisco DCINX9K. The training is focused on Cisco Nexus 9000 switches in NX-OS mode. NX9K can run two different software images, the full ACI image with all the cool SDN stuff…
NeDi and Observium are two of my favourites network monitoring tools. I do like to deploy both, they complete each other and since they’re free there is no need to choose. The only problem with the use of two tools is…
Switch configuration includes many tasks, some of them are just boring and error prone. Vlan port assignment on access switches, excited huh? There can be many vlans (clients, printers, access-point, security cameras and more) and it may not be easy…
Last week I had the opportunity to attend the first Wireless LAN Professionals Conference in Europe. Wireless is an important part of my job, I designed and managed more than a few wireless networks installations and I know there are…