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9 Freewares for Your Cisco CCNA Home Lab
If you decided to build your own Cisco home lab, then I know you're going to need the following freewares for your LAN sooner or later.These freewares I picked not because I think they're the best based on the functions but they are the ones I use in my home lab and what I think most handy for me.
By the way, I used the image above I found on the internet, if you click that image it leads you to a site where they held a freeware logo contest there, pretty cool.
Back again, I'll start with freewares that you can use to connect your PC to your Cisco Devices:
1. HyperTerminal Private Edition
Since Microsoft decided not to include hyperterminal in Windows Vista, you surely need this private edition version of HyperTerminal if you like the look of it.
You can use HT to connect to your Cisco Devices through serial connection or TCP/IP winsock.
2. Putty
Now Putty offers almost everything that you need for data communication, Telnet, SSH, RLogin, Serial Connection, proxy, anything, you name it.
One thing that I very much like from Putty is that I can change the font, color, the appearance of the Putty window.
I like to change it to be the matrix-like console, so I can get a "hacker" feel from it
3. TeraTerm
Now sometimes when given too much offers like in Putty, newbies can get confused. TeraTerm offers the solution between the HyperTerminal and Putty.
It has simpler design than Putty but flexibility to change user interface.
4. Solarwinds TFTP Server
If you're working with Cisco Devices, sooner or later you're going to need TFTP server. TFTP server is used to upload and download file to or from network devices.
You can use TFTP server to save your configuration files, backup your IOS, upgrade the IOS, store DHCP bindings if you're using your router as DHCP server, etc.
5. Kiwi Syslog Daemon
Syslog is used to receive messages from your network devices, and then display them in real time.
If you're using syslog in your LAN, you can find out immediately if your ports or devices are failing, and know exactly the errors are happening.
You can also use this Kiwi Syslog Daemon as an alert system, sending you email when one of the devices in your LAN is failing.
6. Cisco TACACS Server for Windows
This is not a software released by Cisco but more like a custom software based on Cisco source code.
If you don't know what TACACS server is, it is a server that stores your users' credentials such as user names and passwords.
If a user want to access something in your LAN, the TACACS server will check the credentials first before allowing the user to do something further.
The CCNA exam won't test you in configuring TACACS server, but it's fun to configure so try it out.
7. Wireshark
Now this baby is dangerous, you surely know Wireshark (previously named ethereal). It's a protocol analyzer, it can sniff, grab everything that running around in your network and view it.
No, I'm not telling you to sniff on your users data but Wireshark can be a very valuable learning tool for your exam.
You can use it to view what's going on behind the scene when you set up routing protocol or anything else in your LAN, see what things are transferred, see how they interact, etc.
8. PRTG Network Monitor
PRTG Network Monitor from Passler is a powerful network monitoring solution you can used to monitor your network devices, not just Cisco devices, it gathers all your devices' status and display them in graphical report.
There are other tools you can use to monitor your LAN, you can see a list from Cisco, what they recommend for monitoring Cisco devices here:
http://www.cisco.com/warp/public/732/Tech/nmp/netflow/partners/freeware/index.shtml
9. Tenable Nessus
If you want to scan your network for vulnerabilities, you can use Tenable Nessus. It's not exactly necessary for Cisco Devices since you're in control of what ports you're using for your network devices, but you can use Nessus for scanning your users' machines.
More on this you can find at my previous post.
Well, that's it the freewares that you can use in your home lab, there are vendors that produce an all in one solutions for your network such as Solarwinds and Kiwi, of course you have to pay for the advanced version.
This is fun, I found other tools when researching for this post, think I'll use it in my network and share it with you next time.
But, My Laptop Has No Serial Port???
Console cables have RJ45 connector at one end and Serial connector at the other end, the problem with this is that most of the newer laptops produced nowadays don't have any serial port.
Sure the laptops got smaller and lighter, but no serial port? This can be a slight problem for us, network engineers.
There's a way to get around this, we can use Serial to USB Converter cable. What this cable does is it converts your console cable serial connector so you can plug it to your USB port.You can see at the image on the left is an example of Serial to USB converter cable, you can find many vendors produce this kind of cable.
To use it for your laptop is an easy work, all you have to do is install the driver, some cables can just work when plugged in, and sometimes you have to find the driver update first so it can work with your OS.
This happened to me once, I got my converter ready, did the correct parameters for connection but I can't connect to the router.
I search every possible cause for hours only to find that my converter driver need to be updated. So words of note, don't forget to download your driver update.
When you done with the driver installation, the installation window will tell you where is the converter located COM1, COM2, or other.
If not, you can look at your Windows Device Manager and point to the Ports (COM & LPT), there you can find the location of your converter.
I'm not sure if this is true, but whenever you move your usb converter to other usb port, it will change the COM port number.
Just to be safe, remember where you plugged the converter for the first time and always plug there.
Next, you can use the converter to connect to the routers/switches. I used HyperTerminal Private Edition for this example:
Give a name for the connection then choose the COM port of your converter from the Connect using drop down menu.
Make sure you have the following parameters set:
- Bits per second : 9600
- Data bits : 8
- Parity : None
- Stop bits : 1
- Flow control : None
Click OK and you're ready to go.
Fix for High CPU usage when SNMP is enabled in Cisco Routers
Cisco Routers and Switches with L3 routing functions are seen to have problems with High CPU usage when SNMP is enabled. This can range anything from 15% to 40%. According to Cisco, these are low priority processes and other priority processes requiring CPU cycles are given priority over these processes and this level of CPU utilisation can be is normal. However, it is always better to be safe than sorry and get the CPU utilisation caused by SNMP to bare minimum so as to ensure the Routers function smoothly.
(...)
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Howto upgrade IOS on a 3750 switch stack
If you want to upgrade IOS on a 3750 switch stack follow this procedure
There are some new IOS commands to automate upgrading of a stack, but I use the familiar manual method.
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One Source for Pre-Owned, Used, Refurbished and New-Surplus Networking Equipment
Network Hardware Resale (NHR) is the largest provider of refurbished Cisco and used Cisco hardware including Cisco routers, switches and accessories. NHR is also an authorized reseller of new-surplus equipment from Force10, the pioneer in resilient 10 Gigabit and Gigabit Ethernet switching and routing.
NHR carries over $200 million in inventory of used Internet routers and computer network hardware including the full line of pre-owned, refurbished and used Cisco products, Juniper routers, Extreme switches, Redback routers and Foundry equipment. Our extensive Cisco inventory includes Cisco routers, Catalyst switches, access servers, Cisco security products (PIX, VPN and IDS), Cisco IP telephony or VoIP products, content and storage products, as well as all Cisco memory, modules and accessories. All NHR pre-owned equipment is backed by an industry-leading one-year warranty and support from Cisco-certified technicians.
The Network Hardware Resale Difference Over 10,000 organizations worldwide rely on NHR for high-quality, fully-guaranteed networking solutions.
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Setting Port Security on a Cisco Catalyst Switch
If you want to ensure that only a certain device—for example, a server—is plugged into a particular switch port, you can configure the MAC address of the server as a static entry associated with the switch port.
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GNS3 | Home
Howto Setup Cisco Router Auxiliary,Console and Telnet Passwords
There are five passwords used to secure your Cisco routers: console, auxiliary, telnet (VTY),enable password, and enable secret. Just as you learned earlier in the chapter, the first two passwords are used to set your enable password that’s used to secure privileged mode. This will prompt a user for a password when the enable command is used. The other three are used to configure a password when user mode is accessed either through the console port, through the auxiliary port, or via Telnet.
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Howto Recover Cisco Router Password
This ‘How to’ is written to show the step by step password recovery of the Cisco Routers. It is assumed that you have a prior knowledge of what a router is and its basic function. It is also assumed the you are having some experience of configuring the router.
Please do not follow these steps if you are a new to Routers, as this can damage the IOS or any physical interface of the router.
1.Connect a computer to the router’s Console port using the Console cable that came with your router (it is usually flat and light blue).
Use these terminal settings:
* 9600 baud rate
* No parity
* 8 data bits
* 1 stop bit
* No flow control
2.Turn the router off using the power switch and turn it back on.
3.Once text starts popping up on the screen, send the break command CTRL + B or CTRL +BREAK (sometimes it is CTRL +X). This will abort the boot and present you with a rommon 1> prompt
4.From the new prompt you need to change the configuration register using the following command: confreg 0×2142
5.If you are using an older model of router you may need to enter o/r 0×2142
6.Now you need to recycle the router with the reset command.
7.If you used the o/r command then reset the router with the I command
8.Once the router finishes restarting you will find that there are no passwords to deal with, so you can enter enabled mode carte blanche.
9.Once in enabled mode enter this: copy start run. This will copy the startup config to the running config.
10.Now, go into configuration mode with the config t command
11.Once there enter the new password with the enable secret password command (i.e. enable secret admin).
12.Now set the configuration register back to normal with this command: confreg 0×2102
13.Exit config mode and enter the command copy run start to copy the new configuration to ram.
14.Now it is time to reload your router
15.Once the router is back up you need to configure all of your interfaces with the no shutdown command or they will not work.
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Cisco Layer 2 Switch Functions
Layer 2 switch is A network device that forwards traffic based on MAC layer (Ethernet or Token Ring) addresses.
Bridging technology has been around since the 1980s (and maybe even earlier). Bridging involves segmentation of local-area networks (LANs) at the Layer 2 level. A multiport bridge typically learns about the Media Access Control (MAC) addresses on each of its ports and transparently passes MAC frames destined to those ports. These bridges also ensure that frames destined for MAC addresses that lie on the same port as the originating station are not forwarded to the other ports. For the sake of this discussion, we consider only Ethernet LANs.
Layer 2 switches effectively provide the same functionality. They are similar to multiport bridges in that they learn and forward frames on each port. The major difference is the involvement of hardware that ensures that multiple switching paths inside the switch can be active at the same time.
There are three distinct functions of layer 2 switching
1)address learning
2)forward/filter decisions
3)loop avoidance
Address learning
Layer 2 switches and bridges remember the source hardware address of each
frame received on an interface, and they enter this information into a MAC database called a forward/filter table.
Forward/filter decisions
When a frame is received on an interface, the switch looks at the destination
hardware address and finds the exit interface in the MAC database. The frame is only
forwarded out the specified destination port.
Loop avoidance
If multiple connections between switches are created for redundancy purposes,
network loops can occur. Spanning Tree Protocol (STP) is used to stop network loops
while still permitting redundancy.
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Howto Setup Cisco Router Enable Password
There are five passwords used to secure your Cisco routers: console, auxiliary, telnet (VTY),enable password, and enable secret. Just as you learned earlier in the chapter, the first two passwords are used to set your enable password that’s used to secure privileged mode. This will prompt a user for a password when the enable command is used. The other three are used to configure a password when user mode is accessed either through the console port, through the auxiliary port, or via Telnet.
You set the enable passwords from global configuration mode like this
Router(config)#enable ?
last-resort - Define enable action if no TACACS servers respond
password - Assign the privileged level password
secret - Assign the privileged level secret
use-tacacs - Use TACACS to check enable passwords
The following points describe the enable password parameters
Last-resort - Allows you to still enter the router if you set up authentication through a TACACS
server and it’s not available. But it isn’t used if the TACACS server is working.
Password - Sets the enable password on older, pre-10.3 systems, and isn’t ever used if an enable
secret is set.
Secret - Is the newer, encrypted password that overrides the enable password if it’s set.
Use-tacacs - This tells the router to authenticate through a TACACS server. It’s convenient if you
have anywhere from a dozen to multitudes of routers.
Here’s an example of setting the enable passwords
Router(config)#enable secret admin
Router(config)#enable password admin
The enable password you have chosen is the same as your enable secret. This is not recommended. Re-enter the enable password.
If you try to set the enable secret and enable passwords the same, the router will give you a nice, polite warning to change the second password. If you don’t have older legacy routers,don’t even bother to use the enable password.
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Howto setup cisco router Hostnames
You can set the identity of the router with the hostname command. This is only locally significant,which means that it has no bearing on how the router performs name lookups or how the router works on the internetwork.
Router#config t
Enter configuration commands, one per line. End with
CNTL/Z.
Router(config)#hostname debianadmin
debianadmin(config)#hostname london
london(config)#
Even though it’s pretty tempting to configure the hostname after your own name, it’s definitely a better idea to name the router something pertinent to the location. This is because giving it a hostname that’s somehow relevant to where the device actually lives will make finding it a whole lot easier. And it also helps you confirm that you are, indeed, configuring the right device.
Tags: configure router hostname, Network, setup cisco router hostname, setup router hostnameconfigure router hostname, Network, setup cisco router hostname, setup router hostname addthis_url = 'http%3A%2F%2Fwww.debianadmin.com%2Fhowto-setup-cisco-router-hostnames.html'; addthis_title = 'Howto+setup+cisco+router+Hostnames'; addthis_pub = 'david23';©2008 Debian Admin. All Rights Reserved.
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