Some useful commands to work with vi
| i | insert |
| r | replace |
| 9yl | copy nine characters from cursor position, e.g 192.168.1.0 192.168.1 will be copied |
| p | paste what you have copied |
| x | delete character |
| :wq | write and quit (save and close) |
| /search_string | find search_string |
| n | go to next occurrence of search_string |
| N | go to previous occurrence of search_string |
| dd | delete line |
| 10dd | delete next 10 lines |
| yy | copy line |
| 10yy | copy next 10 lines |
| r | replace current character at cursor |
| R | replace current word at cursor |