ubunt to get a iP address by DHCP

After installing the Ubuntu OS ,  if you want let  it to get the ip address by DHCP ,you shoule follow this kind of  step :

1.  to find witch card is your network card  with command :“  ip linik  ”   

for example :

 

in this example we can figure out the "ens33"  is the real card the  physical card.  so we need to configure it .

2. To change the fie of this card. 

the path is : /etc/network 

with 'ls'  we can list the  files  

the target is "interfaces" 

with command "vi intercases" we could change it . for example:

in this example  , i changed the card name with    with my real network card,  witch means ens33.

then save it .

3. restart the sevice of your computer's network  , by " " then  you can get the ip address by DHCP.