Category: Networking
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Power Requirements For Cisco Aironet
You can see the chart here. I have 3 6500 chassis full of PoE blades(WS-X6348-RJ-45). All of them are slightly older and supply only prestandard power. The cards are only able to supply 7 watts max per port, which means you can basically power phones and light APs. I found that my aironet 1200s weren’t…
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Mikrotik X86 Interfaces Always Appear Running
I just recently noticed that some of my server based mikrotiks were showing “R” by ethernet interfaces that I knew were down. I did some quick searching and found that on X86 installs by default there is an option “disable-running-check” enabled. What this does is make the interface appear to always be running. As a…
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Mikrotik – Use The Serial Port To Connect To Other Equipment
It’s sometimes useful to connect the serial port on your Mikrotik over to another piece of network equipment. I don’t need it very often, but it is quite useful for out of band management. The wiki article is here. I made a quick video showing how to connect to a Cisco device. I’m using a…
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Parse Your Cisco Devices To Reconcile Customer Information
Since I work for a datacenter, we have a LOT of ports. Our customers hang off of a handful of pieces of equipment, but we have a lot of density on these devices. Every so often we run the numbers for how much bandwidth is subscribed to each customer as well as how much are…
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What Is The Hidden Node Problem And How Does TDMA Fix This?
With the roll out of TDMA(time devision multiple access – AKA Nstreme2) I’ve heard mention of the hidden node problem…though, no one bothers to mention what the hidden node problem is…it seems the answer to the hidden problem is hidden. Here’s my two second rendition of the issue: 802.11 uses CSMA/CA to handle collisions. Collisions…
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TTL (Time To Live) And Fun With Mikrotik TTL Mangle
Wikipedia will be happy to explain. In a nutshell TTL is a field in the IP header that sets how many routers a packet can traverse. If you have a routing loop and TTL didn’t exist, then the packets could indefinately loop. What’s the problem with that? Packets can travel between two routers with virtually…
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Cisco – VPN Issues From A 6509
I’m doing IPSec tunnels from a 6509 at a remote facility to an ASA. The tunnel would establish, traffic would send from the 6500 to the remote client, the remote client would answer, but it would never go back through the 6500…strange. I noticed that the ASA said that the connection was using NAT traversal,…