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  Check your Network Interface Card cat /sys/class/net/eth0/carrier or, cat /sys/class/net/eth0/operstate if the result is 0 or down , it means your NIC to cable is not connected . if the result is 1 or up , it means your NIC to cable is connected .    

IP Masquerade is a networking function in Linux similar to the one-to-many (1:Many) NAT (Network Address Translation) servers found in many commercial firewalls and network routers. For example, if a Linux host is connected to the Internet via PPP, Ethernet, etc., the IP Masquerade feature allows other "internal" computers connected to this Linux box (via PPP, Ethernet, etc.) to also reach the Internet as well. Linux IP Masquerading allows for this functionality even though these internal machines don't have an officially assigned IP address . MASQ allows a set of machines to invisibly access the Internet via the MASQ gateway. To other machines on the Internet, the outgoing traffic will appear to be from the IP MASQ Linux server itself. In addition to the added functionality, IP Masquerade provides the foundation to create a HEAVILY secured networking environment. With a well built firewall, breaking the security of a well configured masquerading sys...

systemd does not use /etc/inittab file to change the default runlevel. systemd uses symlinks to point to the default runlevel. You have to delete the existing symlink first before creating a new one. # rm /etc/systemd/system/default.target example to switch to runlevel 3 : # ln -sf /lib/systemd/system/multi-user.target /etc/systemd/system/default.target next example if you want to switch to run level 5 : # ln -sf /lib/systemd/system/graphical.target /etc/systemd/system/default.target another options that may apply : poweroff.target --> runlevel 0 rescue.target    --> runlevel 1 multi.user.target --> runlevel 2,3,4 graphical.target --> runlevel 5 reboot.target --> runlevel 6 source: http://fedoraproject.org/wiki/Systemd

basic usage to access the remote server $ rdesktop (serveraddr) example to access the computer on 192.168.1.1 $ rdesktop 192.168.1.1 to enable full screen mode $ rdesktop -f 192.168.1.1 to set spesific windows size $ rdesktop -g 800x600 192.168.1.1 (some common screen resolution can be use: 800x600, 1024x768, 1280x1024) sharing files to share a local directory with windows os remote server $ rdesktop -r disk:(sharename)=(path) (serveraddr) example to access the remote server on 192.168.1.1 and the sharing directory /home/vadya/pub/ using network share name "sharing" $ rdesktop -r disk:sharing=/home/vadya/pub 192.168.1.1 optimizing speed enabling compression (-z) and disabling mouse events (-m) will reduce network bandwidth and can make the connection much more responsive.  $ rdesktop -z -m 192.168.1.1 using a smaller color palette helps reduce network bandwidth $ rdesktop -a 16 192.168.1.1 source: http://wiki.rrc.uic.edu/wiki/RRC-SCS:_Using_rd...