Problem

I have installed the RHEL 6.8 on a server and after assigning the IP address to the system when I restarted the network services IP address changed to local IP.

[root@dbappweb ~]# service network restart
Shutting down interface eth0:                              [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
[root@dbappweb ~]#

Checking the IP details which is showing only the loopback address.

[root@dbappweb ~]# ifconfig
lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:914598 errors:0 dropped:0 overruns:0 frame:0
          TX packets:914598 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:75014763 (71.5 MiB)  TX bytes:75014763 (71.5 MiB)

Reason

The IP address of the system reset to the local because while configuring the IP address on the ethernet card I have selected the value ‘no’ for On boot.

Solution

Use any method of the methods given below:

Change through the command line

• Edit the network configuration file and change the value of the parameter ONBOOT from ‘no’ to ‘yes‘

  [root@dbappweb ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0

  DEVICE=eth0
  HWADDR=b4:b5:2f:55:ce:a8
  TYPE=Ethernet
  UUID=e2f7b63b-a106-4173-ba85-3b931c9a6718
  ONBOOT=yes
  NM_CONTROLLED=yes
  BOOTPROTO=none
  IPADDR=10.20.1.22
  NETMASK=255.255.255.0
  GATEWAY=10.20.1.1
  USERCTL=no
  PEERDNS=yes
  IPV6INIT=no

• Restart the network services and check the IP details

  [root@dbappweb ~]# service network restart
  Shutting down interface eth0:                              [  OK  ]
  Shutting down loopback interface:                          [  OK  ]
  Bringing up loopback interface:                            [  OK  ]
  Bringing up interface eth0:  Determining if ip address 10.20.1.22 is already in use for device eth0...
  [root@dbappweb ~]#

  [root@dbappweb ~]# ifconfig
  eth0      Link encap:Ethernet  HWaddr B4:B5:2F:55:CE:A8
            inet addr:10.20.1.22  Bcast:10.20.1.255  Mask:255.255.255.0
            inet6 addr: fe80::b6b5:2fff:fe55:cea8/64 Scope:Link
            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
            RX packets:5690194 errors:0 dropped:0 overruns:0 frame:0
            TX packets:472539 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:1000
            RX bytes:1016205668 (969.1 MiB)  TX bytes:233489969 (222.6 MiB)
  
  lo        Link encap:Local Loopback
            inet addr:127.0.0.1  Mask:255.0.0.0
            inet6 addr: ::1/128 Scope:Host
            UP LOOPBACK RUNNING  MTU:65536  Metric:1
            RX packets:914598 errors:0 dropped:0 overruns:0 frame:0
            TX packets:914598 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:0
            RX bytes:75014763 (71.5 MiB)  TX bytes:75014763 (71.5 MiB)

Change through the graphical interface

• Run the setup command to launch the graphical interface for the network cards on the system.
• You can see the On boot is not selected for the eth0 in the network configuration.
  

  01 IP Address changed to local after restarting the network services in Linux

• Select the On boot option for the eth0 in the network configuration and save the network configuration.
  

  02 IP Address changed to local after restarting the network services in Linux

• Now restart the network service and check the IP details

  [root@dbappweb ~]# service network restart
  Shutting down interface eth0:                              [  OK  ]
  Shutting down loopback interface:                          [  OK  ]
  Bringing up loopback interface:                            [  OK  ]
  Bringing up interface eth0:  Determining if ip address 10.20.1.22 is already in use for device eth0...
  [root@dbappweb ~]#

  [root@dbappweb ~]# ifconfig
  eth0      Link encap:Ethernet  HWaddr B4:B5:2F:55:CE:A8
            inet addr:10.20.1.22  Bcast:10.20.1.255  Mask:255.255.255.0
            inet6 addr: fe80::b6b5:2fff:fe55:cea8/64 Scope:Link
            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
            RX packets:5690194 errors:0 dropped:0 overruns:0 frame:0
            TX packets:472539 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:1000
            RX bytes:1016205668 (969.1 MiB)  TX bytes:233489969 (222.6 MiB)
  
  lo        Link encap:Local Loopback
            inet addr:127.0.0.1  Mask:255.0.0.0
            inet6 addr: ::1/128 Scope:Host
            UP LOOPBACK RUNNING  MTU:65536  Metric:1
            RX packets:914598 errors:0 dropped:0 overruns:0 frame:0
            TX packets:914598 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:0
            RX bytes:75014763 (71.5 MiB)  TX bytes:75014763 (71.5 MiB)

Note: I have faced this issue in RHEL 6.8.