I did a fresh install of CentOS 7 on an Acer Inspire T.  It is a terminal-only installation (no GUI).  I connected the CentOS 7 box to a cable modem via an ethernet cable, and the cable modem is lighting up at the point of connection to indicate that the CentOS 7 box is connected.  But when I log in as root and type yum install nano, the terminal replies with Could not resolve host: mirrorlist.centos.org.  What do I have to do in order to be able to successfully use yum install commands on this CentOS 7 box?EDIT: As per @MarkPlotnick's advice, I am trying the steps in this tutorialTyping nlmcli d resulted in:  DEVICE     TYPE         STATE         CONNECTIONeno1       ethernet     unmanaged     --lo         loopback     unmanaged     -- wlp3s0     wifi         unmanaged     -- I then type nmtui and get the following screen shot:  http://cdn.krizna.com/wp-content/uploads/2014/08/Setup-network-on-centos-7.png However, in the screen that follows when I chose Edit a connection, the only active options are Add and Quit.  By contrast, the Edit and Delete options are not activated so they cannot be selected. When I click Add, and then Ethernet it asks me for:Profile Name:  Device:Cloned MAC Address:MTU:  I imagine the profile name can be anything, but what do I put for the other three?  When I called my ISP, they told me my MAC address is in the format 11;aa11a1;a1;aa, where a represents some letter, and 1 represents some digit.  But when I try to type this in the field for Cloned MAC address, it forces the format to be 11:aa:11:.... and so on, where the characters are separated by colons at intervals that are different from what the ISP gave me.  Also, the ISP did not know what my MTU is, or what to put for Device.  So how do I find the correct values for these parameters?  Note: When I type dmesg | -i Ethernet, the terminal replies with 0.5056601 r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded.  Does this provide information that we can use to fix this problem and connect to the internet?Also note that /etc/sysconfig/network-scripts/ifcfg-eno1 was changed to allow ssh connections to a different computer when the ethernet cable is connected to that other computer instead of to the internet.  The contents of ifcfg-eno1 are:  [root@localhost ~]# cat /etc/sysconfig/network-scripts/ifcfg-eno1TYPE=EthernetBOOTPROTO=staticIPADDR=192.168.100.2NETMASK=255.255.255.0NAME=eno1UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxDEVICE=eno1NM_CONTROLLED=noONBOOT=yesAs per @garethTheRed's link, I changed /etc/sysconfig/network-scripts/ifcfg-eno1 to:  [root@example ~]# cat /etc/sysconfig/network-scripts/ifcfg-eno1DEVICE=eno1BOOTPROTO=dhcpNM_CONTROLLED=noPERSISTENT_DHCLIENT=1ONBOOT=yesTYPE=EthernetDEFROUTE=yesPEERDNS=yesPEERROUTES=yesIPV4_FAILURE_FATAL=yesIPV6INIT=yesIPV6_AUTOCONF=yesIPV6_DEFROUTE=yesIPV6_PEERDNS=yesIPV6_PEERROUTES=yesIPV6_FAILURE_FATAL=noNAME=eno1
Could not resolve host: mirrorlist.centos.org
centos;terminal;yum;ethernet;modem