Then I decided to work with GNS3 as Root by invoking GNS3 in commandline in with user root. Everthing is going well until I save the project, the problems which occured to me are
1. GNS3 cannot save the workspace outside root directory (it just process as it saved the project, but actually it is not!!)
2. I cannot open project file (*.net) by double click it (open with default application), I have to open it from commandline (but my friend, same os version, has not!!??).
At last, I decided to work with GNS3 in Windows Vista. But the problem mostly occured in Windows Vista is that it does not provide telnet client at first installation. So I have to install telnet client in Control Panel > Program and Features > (on left pane) Turn windows feature on and off and activate telnet client.
Working with Windows telnet is not a comfortavle way for me, then I install the PuTTY for telnet client. The command that we have to config in Edit > Preferences > General > Terminal command is "start C:\progra~1\PuTTY\putty.exe -telnet 127.0.0.1 %p"
---[ For Windows Vista ]---
1. We have to use address 127.0.0.1 instead of localhost (%h) and %p is the router port number for telnet (console connection)
2. We have to change the path to PuTTY from C:\Program Files\PuTTY\putty.exe to C:\progra~1\PuTTY\putty.exe since it will error (Windows thainks that "C:\Program" is telnet program, ToT)
3. the word "start" is to invoke the commandline application
---[ For Both, Windows Vista and Ubuntu Jaunty ]---
1. The path specifies (both workspace and IOS path) in the project file (*.net) cannot use relative path, we have to enter the absolute path only!!