Most firewalls should block [tag]ICMP[/tag] requests to them, so how do you know that your router or server has layer-2 connectivity to one? It’s pretty elementary, actually, but I’ve found that not a lot of people know this trick. If you ping the firewall, it…
Author: jac
Aaron does lots of stuff and, therefore, does nothing well. He's trying, though.
https://masto.ai/@aconaway
I’ve seen a thousand [tag]firewalls[/tag] in my time, and nearly all of them are poorly configured. The biggest culprit? No [tag]outbound[/tag] [tag]filtering[/tag]. I guess a lot of people think that firewalls are there to protect the network from the Internet, but that’s only part of…
Remember the article on router-on-a-stick? And the one on HSRP? Let’s add to that example network, shall we? Let’s make those routers into edge routers so they connect your internal network to the Internet with some size circuit. Let’s just say they each terminate DS3s…
I finally got around to looking into [tag]SNMP[/tag] v3 and was shocked at how easy it actually is. When I first looked up info on it so many moons ago, I saw table after tables of views and privilege levels and thought I would have…
When I started in IT, I tried to get my gear as standardized as possible to impress everyone. I worked at it and worked at it until I realized that there were a handful of things that sound good but just won’t work. If you’re…
By default, most Cisco [tag]IOS[/tag] devices come configured to be accessed via telnet. This is probably fine for your house, but I really cringe when I run across corporate networks that use [tag]telnet[/tag] to access the devices. Telnet is old and out-dated and can be…
I was talking to some guys at work today about scalability and data efficiency, and an example came up that I had to think about for a second. One of the guys, a lead developer, started talking about the difference between 5 spaces and a…
Ever heard of Samba? You should. Samba is an open-source project “that provides seamless file and print services to SMB/CIFS clients.” That’s from the project’s website, but what the hell does it mean? In a nutshell, it’s an open-source application that lets non-Windows machines share…
If you need to buy an Ethernet cable, you’ll pay quite a premium for it at your local CompUSA or Circuit City. $22.99 for a 7′ Ethernet cable is terrible. For just a few dollars more, you can buy a 250′ roll of cable and…
I was talking to a coworker the other day about setting up his home network more securely. “No problem,” I said, and we started listing devices on his network to see what we needed to do. I was pretty surprised that he had so many…