Shulou(Shulou.com)06/02 Report--

What I share with my friends today is the deployment of the GNS3 environment and two testing methods for interoperability.

Before we begin, we need to know what GNS3 is:

GNS3 is a network virtual software with a graphical interface that can run on multiple platforms (including Windows, Linux, and MacOS, etc.). Cisco network equipment administrators or people who want to pass the Cisco certification exam such as CCNA,CCNP,CCIE can use it to complete the relevant experimental simulation operations. At the same time, it can also be used to virtually experience the Cisco Internet operating system IOS or to verify the relevant configuration that will be deployed on a real router.

To put it simply, it is a graphical front end of dynamips, which is easier to use and more operable than using virtual software such as dynamips directly.

GNS3 integrates the following software:

1.Dynamips: a simulator that allows users to run Cisco system (IOS) directly.

2.Dynagen: is the front end of the text display of Dynamips

3.Pemu:PIX firewall device simulator.

4.Winpcap:windows platform is a free, public network access system. Develop the winpcap item

The aim is to provide win32 applications with access to the underlying network layer; to design excellent network topologies; to simulate Cisco routing devices and PIX firewalls; to simulate simple Ethernet, ATM and frame Relay switches; to be able to load and save to Dynamips configuration formats, that is to say, good compatibility for virtual software using the dynamips kernel to support the export of some file formats (JPEG, PNG, BMP and XPM)

Next, I would like to share with you the path of the software you need to deploy this environment in my cloud disk:

Link: https://pan.baidu.com/s/13bRylSWS87xjv_8jN_F7-Q

Extraction code: r99a

After all this folder has been downloaded, the following three files will be used this time:

Now we can install the GNS3 software:

1. First of all, let's double-click the following program to install, where the version we installed is 1.3, which is stable.

two。 Do not check the following two options when entering the steps shown in the following figure, because the automatic download will take a long time when you install it later, and it will prompt you that the download failed

3. Next, let's go into the choice of path. what we must pay attention to at this time is that the path must not have Chinese characters or spaces and symbols:

4. After selecting the installation path and entering the installation progress, you will jump out of the installation interface of the previously selected WinPcap virtual machine, where the options are directly defaulted, and then the installation is completed:

5. After the installation is finished, we click finish, and then the following screen pops up. In this interface, we can see that the YSE option is prompted to be bold, but we need to select NO here, because if we choose, we will be prompted to pay $200 to learn CCNA:

6. Later, we will be prompted to start GNS3. At this time, we are not in a hurry, because the overall environment has not yet been deployed. Then we return to the desktop and get the following GNS3 icon as follows:

Next, let's install Wireshark:

Again, as above, let's take a look at what Wireshark is:

Wireshark (formerly known as Ethereal) is a network packet analysis software. The function of network packet analysis software is to capture network packets and show the most detailed network packet data as much as possible. Wireshark uses WinPCAP as the interface to exchange data messages directly with the network card.

In the past, network packet analysis software was very expensive or dedicated to profitable software. The emergence of Ethereal changed all that. Under the protection of the GNUGPL General license, users can obtain the software and its source code free of charge, and have the right to modify and customize their source code. Ethereal is one of the most extensive network packet analysis software in the world.

Next, we will install the Wireshark software:

We find the following program in the downloaded file and double-click to open it:

Enter the following screen prompt, we need to check the desktop icon display, and do the following:

The path is selected by default, and then you will be prompted to install winpacp in the next step, because we have already installed it before, so check the option here.

Also do not run the software after the installation is completed. Return to the desktop at this time to get the icon shown in the following figure:

At this point we can open GNS3, so we can optimize it.

Choose not to pop up the pop-up box on the welcome screen:

At this point, we will officially enter the GNS3 interface, and jump out of the New Project prompt box to allow us to save and create a new project. At this time, our new project will be saved under the default path. If you want to quit halfway, you can save it directly under this path. When you do it later, you can choose to open it under this path and continue. Here we do not create a new project, but choose to cancel:

At this point, we will take into account the user interface of GNS3. Let me introduce the composition of the interface:

What we need to remind you here is that after installing the image file, you must start GNS3 to optimize, otherwise the occupancy rate of the system CUP will reach 100%, and the computer will be very stuck, so here a special tip must be optimized!

First of all, let's load the image (here the image file ends with .bin). Here we select the c3725 image with the highest version. After loading, we select automatic decompression, and the system will automatically convert the mirrored IOS file to image file.

The latter option is to enter the interface of Idle-PC by default. Here, it is worth calculating for Idle. After later calculation, it is used to optimize the occupancy rate of CPU, so that the computer will not stutter. If we do not calculate here, click finish, and a routing information that has been added will be displayed:

At this time, our new router can be either a router (this router is a service provider router) or a switch by adding a layer 2 service veneer. We can drag the built router into our topology console. At this time, the right side of the interface will indicate the status of the router (red is not on, green is on), and then we can turn on the router. There are two ways to enable it. The above operations are shown in the figure below:

Note: the opening button of the toolbar above is that no matter how many routers or other devices are in the control area, just click or this open button will open all of them.

At this point, if we have two routers, we can connect, as shown in the following figure:

At this point, we click the toolbar to open, the two routers are all turned on, but at this time the CPU occupancy rate will be very high, so we can calculate the Idle value for optimization (Idle value calculation can only be carried out after the router is started, but cannot be calculated when the router is turned off), right-click on the open router, select Idle-PC to enter the calculation, and select the one with the symbol "*" at the end as the optimal Idle value. Then select it, after the application, the utilization of CPU will be reduced. The specific operation is shown in the following figure:

At this point, the status of the router is running. Then we can double-click the router that is already running in the topology area to get its running interface as shown in the following figure. Our later operation is to operate it with commands in this interface:

In addition, the Wireshark crawl package we installed earlier can also be used for data crawling. The specific operations are as follows:

At this point, let's give a simple example:

1. Double-click on the R1 router, and the RR1# mode displayed is privileged because it contains the symbol "#"

two。 We enter the command: disable hit enter, and the result we get is R1 >, which is user mode because it contains the symbol ">"

3. The command that we re-enter the privileged mode is: enable, and the command that returns the privileged input is: disable.

4. At this point, we are typing the command: enter configure terminal and the result is R1 (config) #. This mode is global because it contains (config): the router can be effectively configured in this mode.

The command to return to the upper layer is: exit can enter the beginning when he does not know what the command is all about, and then press TAB to complete and change the words. if he does not know what to write later, he can enter "?" To inquire:

Enter the command: end, you can fall back from any mode to privileged mode.

Let's next set up the router address:

For example: R1 IP address: 192.168.8.8, subnet mask: 255.255.255.0

R2 IP address: 192.168.8.10, subnet mask: 255.255.255.0

Step 1: enter interface fastEthernet 0ram 0 to enter interface mode

Step 2: enter ip address 192.168.8.8 255.255.255.0

Step 3: enter no shutdown (enable the interface)

The specific operation is shown in the following figure:

At this time, the settings of the R2 router are the same as those of R1. Friends can refer to the above actions and set up the R2 router accordingly.

Next, we can verify whether the next two routers are connected, enter the command in R1, enter end into privileged mode, and then enter ping 192.168.8.10 to hit enter. At this time, we can see the status of interconnection. In the case, there are a total of five data, four connected, and one is not connected, not connected to general purpose. " It means to get through with "!" It means. In addition, we can also use packet capture to obtain the transmitted data. All operations are as follows:

We can also use CRT to open commands for the above operations

Again, let's take a look at what CRT is:

SecureCRT is a terminal emulation program that supports SSH (SSH1 and SSH2). To put it simply, it is the software that logs into the host computer of UNIX or Linux server under Windows.

SecureCRT supports SSH, as well as Telnet and rlogin protocols. SecureCRT is an ideal tool for connecting operations, including Windows, UNIX, and VMS. Encrypted files can be transferred by using the included VCP command line program.

Next, we install CRT. At this time, the CRT file we downloaded is a compressed package, and we need to extract it to the current folder. (it should be noted here that the Microsoft antivirus software included in the computer has file monitoring and isolation, and this function is turned off in advance. In order to prevent one of the important programs from being automatically deleted after decompression, you need to enter the password after clicking the decompression: SPOTO. Double-click the application shown in the following figure in the unzipped file to open and run the installation:

After entering the default settings for installation, select a shortcut to create on the desktop, do not modify the installation path by default, and do not run it for the time being after the installation is completed. Click finish to return to the desktop and you will get the desktop icon as shown below:

At this time, if we open the software directly, there is only a 30-day trial period, and there will be a charge if we want to use it after the end.

Next, it's time for welfare! At this point, we need to use the cracking patch under the unzipped file, but we cannot use it directly. We need to put this application under the installation path of CRT. The specific operation process is shown below:

At this point, the cracked patch package in the working directory must choose to run as an administrator to get the following interface:

Then click on the lower left corner of the Patch, will automatically enter the working directory, at this time will jump out of the CRT application, click on it to choose to open will display the successful interface, click OK will pop up the working directory again, this time shows the LicenseHelper application, click it to choose to open will also jump out of the success prompt, then click OK to enter the CRT software to enter the secret key.

At this point, we double-click to open the CRT application on the desktop, jump out of the path and go to the next step, select enter the activation code, and then enter the contents of the crack patch into the activation bar and click finish, as shown in the figure below:

Then CRT will pop up a setting, select the option shown in the figure, and click OK. At this time, the CRT can be used and is permanently activated, and then select the access form, as shown in the figure below:

At this point, we go to the GNS3 simulator to set up the relevant settings:

1. Click Edit to edit and select settings

two。 In Console applications in General, you can see that the default terminal is putty.exe.

3. At this point, we need to set it to remote CRT software, select SecureCRT after the drop-down, and then click Set to update the path.

4. Click OK to finish

The specific operation is shown in the following figure:

Later, the way to open the middle section in GNS3 is to use CRT to open it, and we will try it:

Step 1: pull two routers to the console and connect them with a network cable (R1 and R2, respectively)

Step 2: click to start running

Step 3: when we double-click R1, we will automatically jump the interface to CRT.

Step 4: double-click the R2 router at this time, and it will automatically jump to a new window in CRT. If we want to switch back and forth between the two interfaces in CRT, the buttons we press are: Alt+1 and Alt+2.

At this point, our experiment is successful, and we can open CRT remotely in GNS3.

Because there is a simulator in GNS3, our next experiment is to verify the interconnection of two virtual PCs in two ways.

The first one is to use the built-in VPC to connect the switch and interwork.

Step 2: we pull out a router in GNS3 and change its display name to SW (switch)

Step 3: change the icon to the switch

Step 4: change the configuration and add a two-layer veneer

Step 5: drag two more VPC at this time, and use the network cable to connect with the switch respectively. What you need to note at this time is that the interface of the router begins with 0 in the switch, and the interface of the layer 2 veneer switch begins with 1. After the connection is completed, click to display the port.

Step 6: click on all to configure the switch SW. Double-click the icon of SW to enter the remote CRT

Step 7: enter conf t to enter global mode, and then enter no ip routing (turn off routing function), and then turn off routing function to become the switch.

Step 8: at this time, we double-click the following PC1 and PC2 to generate two interfaces in CRT, and then we first assign the IP address to PC1. Enter: ip 192.168.8.8 255.255.255.0, enter: enter to configure the IP address and subnet mask. The operation in PC2 is the same input: ip 192.168.10 255.255.255.0, enter the IP address and subnet mask.

Step 9: at this time, we can verify whether the two PCs can communicate with each other. At this time, we use PC1 input: ping 192.168.8.10. The specific steps are shown in the following figure:

If it is shown that it is interoperable, the experiment is successful.

The second is to use Vmware to connect the interconnection of switches in GNS3.

Step 1: clear the PC in the console and connect the network cable, leaving only the SW switch

Step 2: open the Vmware virtual machine and open two win10 clients

Step 3: set up the network card. The VMnet settings bound to each network card are different. Select a WWIN10 client, right-click the network selection settings in the lower right corner, select custom at the network connection, and select VMnet1 (host mode only).

Step 4: at this time, the two clients need to configure a network card respectively. At this time, we click the edit on the upper toolbar, select the virtual network editor, in which we can add VMnet, click to change the setting and select the network bit: VMnet2, click add drop-down to select the network bit: VMnet2, click OK to add it. It is important to note that one of them uses DHCP service to assign the IP address to the virtual machine. Do not check this item in order to avoid conflict. At this point, our second client can set the network to custom VMnet2 (host mode only) as described in step 2.

Step 5: go back to GNS3, click on the icon bar on the left, select the PC client, select Host, drag two Host hosts to the topology console, and click to connect with the network cable. At this time, VMnet1 is selected on the host1, connecting the 1x0 port on the switch, and VMnet2 is also selected on the host2, which shows the port and opens all ports.

Step 6: set the IP address and subnet mask on the virtual machine. We select network and network sharing center in a win10, change adapter settings, right-click on Ethernet selection properties, IPv4 protocol, enter IP address 192.168.8.8, subnet mask generation: 255.255.255.0 The other win10 has the same operation before. Enter the IP address 192.168.8.10 in the IPv4 protocol and generate the subnet mask as 255.255.255.0.

Step 7: before whether the ping is connected, you need to turn off the firewall of the two win10 clients, because the packets cannot be intercepted the same when the firewall is on.

Step 8: when entering GNS3, we use Host1 ping Host2 to select grab packet at Host2 (right-click on the network cable from Host2 to switch and select to enable grab packet, interface select 1Make1)

Step 9: enter the first win10 client (this one of IP:192.168.8.8), call out cmd, enter the command: ping 192.168.8.10-t (long spell), hit enter, then the interconnection is displayed in the cmd, and the data interconnection between the two hosts is also shown in the data capture packet.

The specific steps are shown in the following figure:

All the above experiments and steps show that our environment deployment and two interoperability tests for GNS3 today are successful.

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