1. Create new file with editors, vi, pico, nano and so on.
Linux_Srv> pico script_batch
2. Edit the file
#! /bin/sh or #! /bin/bash (whatever you are currently using shell)
ifconfig eth0 192.168.11.1
:
:
[whatever you want to execute when system bootup]
3. Save
4. Make it executable
Linux_Srv> chmod +x script_batch
5. Copy the file to /etc/init.d/
Linux_Srv>cp script_batch /etc/init.d/
6. Update the system
Linux_Srv>update-rc.d script_batch defaults
7. Reboot the system and the script will be automatically executed.