When it comes to building your toolbox we all have a few select favorites. Many tools come and go but there are those that have stuck around for the long haul. The ones you install on new computers and the ones you keep on a thumb drive, for portability.
Below is a list from my toolbox, 7 free tools for Network Administrators.
Once called Ethereal, this application is handy for troubleshooting networks and applications. With the plethora of options available, you can filter by protocols, IP addresses, and more.
Additionally, it makes a great learning resource for understanding TCP/IP communications.
Because Wireshark is such a powerful tool, I recommend reading Laura Chappell’s Wireshark 101.
This application makes it easy to do maintenance tasks such as uploading firmware to network devices and downloading backups of configuration files from network devices. If you have a template configuration file you can also upload them using TFTPD32.
My #1 most-used tool. Whether it’s consoling, ssh, or telnetting into a switch this is the application I use. It’s lightweight and simple to use. I can log all of my output to a text file which I have written about previously. It also interfaces with SuperPutty if you like using tabs.
This open source tool is used for graphing. It utilizes RRDTool, templates, and data acquisition methods to graph your network. I primarily use it to graph interfaces of my switches and routers. The result is a nicely formatted trend of your data utilization.
Installing Cacti does require Linux knowledge. Cacti 0.8 Beginner’s Guide helped me install and understand Cacti.
Before I discovered RANCID I was manually backing up my routers and switches configuration files. There were times where I was devastated because a router failed and I had no documentation of it’s configuration. Time was wasted reconfiguring the router. With proper configuration, RANCID will use cron to log into your network hardware and download a copy of it’s latest configuration. This saved my ass so many times. You get plenty of sleep knowing your config files are backed up regularly.
Angry IP Scanner
I find myself using this often to see what devices are active on a subnet. You can give it a range or have it scan a subnet and it will let you know if a host was alive on a specific IP address and what hostname was discovered on that IP.
Not exactly free but if you buy Cisco you probably have millions of these. One component Cisco doesn’t give you is the USB adapter. The latest hardware has a mini USB console port now but the last time I used it I was unable to get it working.
I keep a console cable with me at all times. My recommendation is to keep a couple of the USB to serial adapters. Keep one in your bag and keep one in the car. You’ll never know when you need it.
If you’re studying for your CCNA be sure to check out:
While not official resources they are excellent additional study material.
There are endless amounts of tools available to get the job done. Which one you use will be based on preference and ease of use. In the list above, all but two are simple to use and install. RANCID and Cacti take a little more effort to get them working properly.
Of all the tools, Putty and Cacti are my favorite. I use both all the time at the workplace. There are new tools introduced every year and some which are catered towards specific scenarios.
What tools do you use?