top of page
Search
kingkatharina1984

Download Ios Image Cisco Router 2600: A Comprehensive Tutorial



This document explains how to download a software image to a Cisco 2600/2800/3800 Series Router using Trivial File Transfer Protocol (TFTP) over the first LAN port using the ROMmon tftpdnld command.


Note: As detailed in Cisco bug ID CSCdk81077 (registered customers only) , for Cisco 2600 and 1720 Series Routers running the ROM monitor command tftpdnld, the command might report a bad checksum comparison when it loads Cisco IOS software images of Cisco IOS Software Release 12.0(2.2)T or later.




Download Ios Image Cisco Router 2600




Xmodem can be used on a group of routers (see Components Used) and is used in disaster recovery situations where the router has no valid Cisco IOS software or bootflash image to boot from and hence, only boots up in ROMmon. This procedure can also be used where there are no Trivial File Transfer Protocol (TFTP) servers or network connections, and a direct PC connection (or through a modem connection) to the router console is the only viable option. Because this procedure relies on the console speed of the router and the serial port of the PC, it can take a long time to download an image. For example, to download Cisco IOS Software Release 12.1(16) IP Plus image to a Cisco 1600 Series Router with a speed of 38400 bps takes approximately 25 minutes.


It is also important to note that the -sdata-rate option is only available on the Cisco 1600 Series Routers and was implemented to overcome the console baud rate limitation of 9600 bps. If you specify -sdata-rate of 115200 bps for example, you can increase the download rate and hence, reduce download time. Other Cisco routers support console speeds up to 115200 bps. Therefore, the -sdata-rate option is not required.


Ensure that the PC serial port uses a 16550 universal asynchronous transmitter/receiver (UART) if you download a Cisco IOS software image through the router console speed at 115200. If the PC serial port does not use a 16550 UART, it is recommended that you use a speed of 38,400 or lower.


In this example, configure Windows HyperTerminal for 8-N-1 at 9600 bps and connect your PC serial port to the console port of the router. Once connected, you need to get into the ROMmon prompt (rommon 1>). Typically, if the router software image and bootflash image are both corrupt, the router only comes up in ROMmon mode. If the former is not true and you need to get into the ROMmon prompt, you need to change the configuration register (typically 0x2102 as given by show version ) to 0x0:


6. Per the message above, you need to exit your 115200 bps HyperTerminal session and restart a new one at 9600 bps. Once connected, the router ROMmon prompt appears. Verify that the download was successful with a dir flash :


This example Windows HyperTerminal is configured for 8-N-1 at 9600 bps. Connect your PC serial port to the console port of the router. Once connected, get into the ROMmon prompt (rommon 1>). Typically, if the router has a Cisco IOS software image and a bootflash image that are both corrupt, the router only comes up in ROMmon mode. If the former is not true and you need to get into the ROMmon prompt, then you need to change the configuration register (typically 0x2102 as given by show version ) to 0x0 as follows:


The standard procedure uses the default console speed of 9600 bits per second. Xmodem is a slow transfer protocol, and the transfer of a file as large as a Cisco IOS software image could take an long time. An increase to the console speed on the 3600 router helps decrease the time it takes to do the xmodem file transfer.


It would be nice if your idea worked of taking an image file from an 1800 and loading it on a 2600. But this would not work. There are things in each image file that are unique to the platform on which it runs. If you could get an 1800 image loaded into flash on 2600 then the 2600 would refuse to load the image.


Yes that would be your chance to get the IOS copy. I am not sure what you are doing/plan to do with your 2600 but one thing to be aware of is what feature set is supported in the image of your current 2600 and what feature set is supported in the 2600 that you may find. Basic routing is certainly supported in any feature set. But if you want to do SSH then you need to make sure that the image includes crypto support. Some of the advanced features for the router require certain feature sets. Good luck in your search.


After downloading one of the iOS images to your computer, you can watch the video below to add the image file to the Graphical Network Simulator-3 and also subscribe to our YouTube channel to support us!


GNS3 offers multiple ways to emulate IOS. For older images, we use and maintain Dynamips; an emulator dedicated to emulate some Cisco hardware. Dynamips can run unmodified IOS images. In the new GNS3 1.4, there is a way to run a second category of switches and routers. These are classified as Routing and Switching virtual machines (or R+Svms) for short. What are the differences? Here are the major differences:


The steps to download IOS of the real router to your PC are as followsWiring the real router to the PCConfigure the real router as a TFTP serverDownload IOS with your PC TFTP clientWiring the real router to the PCWire the actual router and PC to which you want to download IOS. Connect the Ethernet interface of the router and PC with a UTP cable. Since you need to configure the router, you also need to connect the console.


Download the IOS file from the actual router using the TFTP client on your PC. and you can install an additional TFTP client on Windows 10. Configure an IP address/subnet mask that can communicate with the router and download the IOS file from the command prompt using the tftp command.


If the IOS upgrade goes smoothly and the checksum verifies correctly, then it is safe to reboot your router to load the new IOS image. Once the router becomes reachable again, you should verify the new IOS loaded correctly with the show version command:


So far we copied a couple of files but how do we know that these files are valid? When we downloaded the Cisco IOS image, I showed you the MD5 checksum that Cisco publishes on their website. We can verify this checksum on our router:


Most routers will select the first filename that they find on the flash memory so in our case, it means it would boot the older IOS image. We can change this with the boot sytem command:


You have now learned how to upgrade your Cisco IOS image through TFTP, FTP and SCP. You have seen how this can be done from your computer to your router/switch or between two routers. We also checked how to verify the integrity of the file with the MD5 checksum and how to configure your router to boot the new IOS image.


Dynamips is a Cisco router emulator. Supported platforms are 1700, 2600, 3600, 3700 and 7200 routers. Each IOS has an associated Idle PC value. Idle PC is used to map the idle instruction of the running IOS to the idle instruction of the UNetLab platform. With a good Idle PC value, the CPU usage should be less than 10% for each instance.


The MD5 File Validation feature allows you to generate the MD5checksum for the Cisco IOS image stored on your router and compareit to the value posted on Cisco.com to verify that the image onyour router is not corrupted.


You can obtain the MD5 value for your system image from theSoftware Center at Cisco.com. The most convenient way to get thisvalue is to click the name of the file prior to download. Forexample, if you select the 12.2.2T4 Release for the 3640 Platformwith the Enterprise Plus Feature Set, before clicking the Downloadbutton, you can click the filename for the image(c3640-js-mz.122-2.T4.bin) and the image information will bedisplayed.


Image information typically includes the Release, Description,File Size, BSD Checksum, Router Checksum, Date Published, and MD5value for the image. You should record the MD5 value for the imageprior to download. However, if you do not have the MD5 value for apreviously downloaded image, you can select the same image onCisco.com (using the same process you would use to download theimage) to get the MD5 value.


Replace 10.253.15.72 with the IP address of your PC, andreplace c2600 with the name of your IOS. (You can locate the name of the IOS onthe working router using the show flashcommand.)


On the console of the nonworking router while in ROMmonmode, use the set command to displaythe current settings, which the program will use to download the IOS via TFTP. (Fora Cisco example of these steps, check out this Ciscodocumentation.)


On a final note, keep in mind that different models of Ciscorouters and different Cisco firmware versions respond differently. For example,these commands performed on a 2600 series router may not work on a 3600 seriesrouter. However, the basic process remains the same.


I used this method to convert a ciscoap3502 putting a ip on interface g0 . I can ping int intraface for a short time.When I try to run. archive download-sw /force-reload /overwrite t -k9w7-tar.defaultError opening t -k9w7-tar.default no shuch file or directory


I downloaded a fresh IOS Lwapp image from the Cisco Support online.Finally, TFTP came to rescue. The AP was at a remote location so I was hesitating from using this step. But it worked perfectly.


GNS3 is free network simulator software. It emulates and simulates routers, switches, and other networking devices. Cisco uses proprietary software for its routers and switches. This software is known as Cisco IOS. GNS3 can run Cisco IOS. Since Cisco IOS is protected by copyright laws, GNS3 does not include any Cisco IOS in its default installation. It only provides a platform to use Cisco IOS, but it does not provide any Cisco IOS itself. To use a Cisco device in GNS3, you need to download and import its IOS to GNS3.


All installed IOS image files are listed in the right pane of the Dynamips -> IOS routers option. Select the file which you want to manage. Once the IOS file is selected, control options will be highlighted in the bottom section. 2ff7e9595c


0 views0 comments

Recent Posts

See All

Comments


bottom of page