Tim’s Network Corner

Upgrading a 3550/3560 IOS can be done in serveral ways which depend on what you want to upgrade and how you want to upgrade.

First of all your upgrade probably depends on what you want to upgrade:

A. Only upgrading the IOS, not the GUI web interface.
B. Upgrading the IOS and the web GUI ( IOS Package)

When only upgrading the IOS, only the .bin file is uploaded to the switch. When upgrading the IOS and web GUI you probably have downloaded/received a .tar file from Cisco. The tar file contains both the .bin file and a directory with web files.

The upgrade itself can be done in 4 ways:

1. By using the web GUI
2. By using the Cisco Network Assitant ( downloadable from the cisco website for free )
3. By using the copy tftp: flash: command
4. By using the archive command

1. The web GUI
The web GUI is an easy way to administer the switch when nothing more then a network connection and a webbrowser is available. It can be accessed by going to http(s)://IP_SWITCH:8080. Once done, you are able to click on the top of the screen on “software upgrade” to select a new IOS package and upgrade the software.

2. The Network Assistant

The network assistant is a tool that is very usefull for daily maintenance of Cisco Network devices. It actually contains a build in TFTP server which is used for upgrading the IOS’s. When logged on to the Network Assistant click on the “Maintenance” tab and than on the “software upgrade… “sub menu. It then shows all switches and switchtypes with the current IOS installed. Select the ones you would like to upgrade and click “upgrade settings”. You are then asked to supply the mode of upgrading, use the internal TFTP server (normal) or use a remote TFTP server and to supply the tar archive file or the path and ip adress of the remote tftp server, depending on which mode has been chosen.

3. Copy tftp: flash:
3550 switches have a minimum of 16 MB flash memory. A standard IOS is probably around 6 MB in size, so you can store 2 IOS’s in the switch at the same time. Make sure there is enough space before copying an IOS or IOS package.

The command show flash: or dir flash: will show you the contents of the flash memory and the free space on it. To use this method to install a new IOS package, you probably do not have enough space on the flash memory. Because besides to the current installed IOS and the copied .tar file, the contents of the .tar file should be extracted and this normally is more than 16 MBs in size. So the copy tftp: flash: command is usually used when upgrade the IOS only. To free up space the old ios can be deleted by entering the following command:

delete flash:/c3550-i5q3l2-mz.121-13.EA1.bin

When enough space has been freed the new IOS can be downloaded to the switch from TFTP.

copy tftp://10.0.0.1/IOSPATH/IOSNAME.bin flash:/NEW_IOS.bin

If you have several IOS’s on the system, you have to prevent it from booting the wrong IOS.

boot system flash:NEW_IOS.bin makes sure the right IOS is booted when the switch rebootes.

reload the switch to load the new IOS

4. The Archive command.
The archive command is easier to use then the previously described method because it automates the commands used above into one command.
For example: It can copy and extract IOS packages, delete old ioses and set the boot parameter to the newly installed IOS.

The syntax of the (in my opinion) most common used command is as follows:

archive download-sw source
/leave-old-sw : Keeps old IOS software on the switch
/overwrite : Overwrites all IOS software files
/reload : Reload when software has been installed
/safe : Don’t change anything, just install the IOS

The source can be a http, https, ftp or tftp URL. When credentials are to be used for the server, these can be supplied by prepending username:password@ in front of the server URL.

An example of the command could be: archive download-sw tftp://192.168.20.2/c3560-ipbasek9.tar.gz