First of all, it can´t be considered an installation as such. To run B-header in your router you just need to save the Tcl code file in your flash memory and call it from the CLI terminal. However, there is an alternative method in case you don´t want to mess with files in your flash or where you don´t have access to a TFTP server. This is explained below in the Method 3 section. If using a TFTP server, I recommend Tftpd32. It is easy to download, install and use.



Transferring and copying the script files from the TFTP server to the router´s flash memory. This way, the scripts can be stored permanently and executed internally.

Einstein# copy tftp:// flash: bheader.tcl
Destination filename [myscript.tcl]?
Accessing tftp://
Loading tcl/myscript.tcl from (via FastEthernet0): !!
[OK - 7200 bytes]
7200 bytes copied in 0.256 secs (36328 bytes/sec)



Manually copying and pasting the scripts onto the router´s flash directory straight from the computer. This method has the advantage of not requiring a TFTP server and is practical in situations where a TFTP server is not available or where connection issues between the router and the TFTP application occur.The following script is an example of how to manually cut and paste a file from the PC directly onto the router´s flash memory without the need of a TFTP server. After entering the Tcl interpreter with tclsh, pasting the script code within the indicated brackets will save the file in flash. Alternatively, this can be prepared in the PC and copy-paste at once on the tclsh interpreter.


puts [open "flash:myfile" w+] {
  *** paste script here... ***



Executing the scripts stored on the TFTP server by invocation from the router´s Tcl interpreter. This method proved to be useful during iterative prototyping and allowed for rapid testing of modified code. In the screenshot below, the script file interfaces.tcl is executed remotely from the router.





Someone's sitting in the shade today because someone planted a tree a long time ago.

- Warren Buffett

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