If you are a network administrator, be sure to upgrade to Windows systems are very familiar with. Under normal circumstances Windows security vulnerabilities announced every month, and given the appropriate patches. But this does not mean that your network of Windows systems only require periodic upgrades and patches: for Cisco routers and switches, the same system should be regularly upgraded.
Unless your company has full-time network management team, or for work upgrading routers and switches are usually ranked in the bottom of the list of work, and work the top of the list are generally Windows systems the task of upgrading and patching. Of course, Windows systems, compared with Cisco equipment, there are more vulnerabilities, so they give priority to upgrading Windows system and no errors.
However, the list of your work on routers and switches, system upgrades should not be placed in the most important position. The priority of this work to judge a number of factors, including the following three:
* Patch for serious flaw: and other network devices or applications, like, Cisco routers and switches will be vulnerable. Also, because the network routers and switches are all an important part of architecture, it must immediately be repaired vulnerabilities exist.
* Add new feature: unless the bug is only for repair, or most of the new version of Cisco IOS will include some new features. Routers and switches periodically update the system, means you can increase the adoption of the new features make their job easier.
• Keep the latest version: "The latest version of" perhaps the most indefensible updated sound reasons. At that time, if your router IOS need to interact with a variety of different tools work, then it becomes important to maintain the latest version of the. For example, if you are using SNMP network management tools, then you must make sure that the router using the appropriate version of the IOS.
Once you have recognized the routers and switches should be upgraded, what to do next? Maybe you have not upgraded the router a long time, perhaps you have never done so, then you definitely need some guidance. To help smooth upgrade, I will guide you step by step upgrade of the Cisco IOS operating (this paper, we address the routers, switches, upgrade, with similar).
Set point
First, for each of the network routers and switches, you have to know their type, RAM size, Flash memory size, and the IOS version currently installed. Through the show version command, the above can be queries to.
Router # show version
Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-IS-L), Version 12.3 (12), RELEASE SOFTWARE (fc3)
Technical Support: http://www.Cisco.com/techsupport
Copyright (c) 1986-2004 by Cisco Systems, Inc.
Compiled Tue 30-Nov-04 02:33 by kellythw
Image text-base: 0x03094EA4, data-base: 0x00001000
ROM: System Bootstrap, Version 11.0 (10c) XB1, PLATFORM SPECIFIC RELEASE SOFTWARE (fc1)
BOOTLDR: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0 (10c) XB1, PLATFORM SPECIFIC RELEASE SOFTWARE (fc1)
ccie-termserver uptime is 1 week, 5 days, 2 hours, 17 minutes
System returned to ROM by power-on
System restarted at 13:55:11 CDT Wed Apr 20 2005
System image file is "flash: / c2500-is-l.123-12.bin"
Cisco AS2511-RJ (68030) processor (revision K) with 14336K/2048K bytes of memory.
Processor board ID 22798335, with hardware revision 00000000
Bridging software.
X.25 software, Version 3.0.0.
1 Ethernet / IEEE 802.3 interface (s)
1 Serial network interface (s)
16 terminal line (s)
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read ONLY)
Configuration register is 0x2102
Router #
From the above example, we can see the router type is Cisco 2511, IOS version 12.3 (12), Memory 16 MB (14,336 K + 2,048 K), Flash memory 16 MB.
In the option to upgrade the IOS image, the above information is important to choose basis. I recommend these to keep the information written to a table. So that when we next upgrade at the time of this router, you can not repeat the query device information, saving time to upgrade.
Find suitable IOS image
Next, is the information by the above query to search for a suitable IOS image version. Remember that the official must obtain from Cisco Systems IOS image, while maintaining institutions must have official contact.
In fact, if you do not enter a user name and password, you can not access the Cisco Software Download Center. Because of this reason, I explain in the next will screenshot with the appropriate site to facilitate them to learn. Figure A shows the user logs on the software center of the web interface.
Figure A
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Click the link to enter Cisco IOS Software Cisco IOS Software page, as shown in Figure B.. Then click on what you want to upgrade to the Cisco IOS software name. Listed here are generally the latest version, but if your router memory or Flash memory is too small, you may only use the earlier version of IOS.
Figure B
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In this case, I chose the IOS 12.3 (although the latest version is 12.4, but 12.3 can be considered a relatively new). Click the version of the link, the browser version will enter into detailed data page, which contains version information, hardware compatibility lists, bug lists and other information, as shown in Figure c.
Figure C
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Then click on the link to download, and you will see IOS Upgrade Planner, as shown in Figure d. As the upgrade Cisco IOS is a complex process, so by Cisco IOS Upgrade Planner to help users select the correct IOS version. Users only need to fill in the device type, memory size, Flash memory size, and can demand.
Figure D
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Using the Cisco IOS Upgrade Planner, you must choose three options: platform, version and software feature set. Remember, not every router can be installed on all versions and all of the feature set, and often appears you are using a router does not support the feature set you want the situation. So usually, you need to you want to have the feature set to select a version of IOS (not necessarily the most recent version) to make this feature set in your router to work.
Also, be sure to enter the correct version number, to ensure that you download a stable version of IOS. There are many versions of Cisco IOS, the differences are as follows:
· GD - General deployment release, is the most stable version.
· ED - Early development version, which means there will be more bug.
· LD - limited edition
· DF - Extended Edition
For our network equipment, generally should be installed GD version, This is the largest patch contains the latest version. In this case, my old 2511 router expect from the current 12.3 (12) version upgrade. First, I will select Cisco IOS Upgrade Planner router platform (2501-2525), and then select the IP PLUS feature set. After the system will limit my choice in a few IOS version, as shown in Figure e.
Figure E
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Next, I would choose a newer version: 12.3.13a (LD). (For example, the reason I did not follow the conventional choice GD version). The next page is very important, it contains selected IOS version of the system demand, as shown in Figure f.
Figure F
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We note that this version of the IOS router equipment needs with 16 MB RAM and 16 MB flash memory. Therefore, before making the next step, we need to check the equipment back the information to see whether the IOS needs. Over time, the new IOS will gradually increase in size, which requires the old section of our routing equipment to upgrade the memory and flash memory in order to install the new version of IOS.
In this case, I was lucky, no need to upgrade the router memory and flash memory you can install new IOS. If you're not so lucky, you must upgrade to install the selected version, you can try to turn around and choose a different functional groups (such as options, rather than IP ONLY IP PLUS), this functional group on the demand for flash memory and lower. Or you can go back to select a smaller version of IOS.
Click I Agree button and agree to the end user license agreement (EULA) can be downloaded after the upgrade version of the IOS image has. Figure g shows. .
Figure G
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Click the download link, the system will ask what position you want to save the file. Usually I would save the C: drive.
Test new version of IOS
If your network is small, or only one or two routers you need to upgrade, then do not conduct any testing. On the contrary, for medium-sized network environment, the new IOS test link is very important. Testing process is as follows:
One. In the standby router IOS tests download
2. After testing, consider how to deploy to the remote router. Because you already know the IOS system requirements, it should first consider whether all of the pending upgrade IOS routers are in line with the demand for memory and flash memory. Do not forget to upgrade the hardware upgrade will greatly increase the time needed IOS.
3. Time to upgrade a router, and will upgrade the timing of non-working hours (including the upgrade download the file to work on the router). If you do not have enough bandwidth, it is best to burn CD in the new version of IOS, and router operating on the host's local PC, or copy the IOS to the PCMCIA card and insert it into the corresponding slots in the router (such as the 3600 series router).
Started to upgrade
With IOS, we need to TFTP server before upgrading the IOS image downloaded to the router. I tend to use TFTP server does not need to install a small software TFTPD32.exe, you can download the software online for free. TFTP server can use other, other, we can even use another Cisco router as a TFTP server.
Between the router and TFTP server to connect with the PING test. Then use the copy tftp flash command to copy the new IOS image to the router. (Need to enter the TFTP server's IP address or server name).
Also the copy before the system will ask whether to erase existing Flash memory. Usually in the IOS upgrade, we will select erase existing Flash memory contents. The following is an example of operation:
Router # copy tftp flash
Address or name of remote host []? 10.253.1.1
Source filename []? C2500-is-l.123-13a.bin
Destination filename [c2500-is-l.123-13a.bin]?
Accessing tftp: / / 10.253.1.1/c2500-is-l.123-13a.bin ...
Erase flash: before copying? [Confirm] yes
Erasing device ... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee ... erased
Loading c2500-is-l.123-13a.bin from 10.253.1.1 (via Serial0/0.1): !!!!!!!!!!!!!!!!!!!!!!!
Verifying checksum ... OK (0xA6B7)
931088 bytes copied in 205.461 secs (4532 bytes / sec)
Router #
[Note: I deliberately cut the IOS file size small to reduce the copy time]
Restart the router
This is the final step in IOS upgrade process. If you are upgrading in non-working hours, then immediately after the upgrade to restart the router, see the updated system can work properly.
And if you are at work on upgrading the router, you can wait until after work and then restart the router. In addition, we can set the router automatically restart the command reload at the time.
After rebooting, double-click each of the function should check the router and the importance of communication between the host, view the configuration file is still preserved the contents of your previous configuration. In general, a major upgrade may result in the loss of some function or configuration file is reset.