Configuring the Loopback Adapter on Microsoft Windows
One of the most missed configuration issue when installing Oracle Database on Windows systems is failure to configure the Loopback adapter prior to installing the software on DHCP clients. Many Oracle products such as Database Control, Database Listener, Weblogic Server either standalone or bundled in JDeveloper use the machine IP address and or host name during the installation and may fail to function properly when either changes.
You can prevent this issue by configuring the Loopback Adpater on your DHCP machine prior to installing Oracle products. This document will detail the setup and configuration on Windows hosts in particular this install was done on Windows 7 Ultimate.
Run the Command Prompt using Run As Administrator and enter
hdwwiz.exe to start the Add Hardware Wizard.
Click the Next button to continue.
Select the “Instal the hardware that I manually select from a list (Advanced)” and click the Next button to continue.
Scroll down and select Network adapters and click the Next button.
On the Select Network Adapter screen select Microsoft for the Manufacturer and select Microsoft Loopback Adapter for the Network Adapter. Click the Next button to continue.
On the confirmation screen click the Next button to install the Microsoft Loopback Adapter.
Once the installation is complete click the Finish button to exit the Add Hardware Wizard.
Now we need to configure the adapter. In the Control Panel open the Network and Sharing Center. Click the Change adapter settings on the left hand side of the panel.
On the Network Connections screen select Local Area Connection with the type of Microsoft Loopback Adapter. Right click the adapter and select properties.
On the Properties pages select Internet Protocol Version 4 (TCP/IPv4) and click the Properties button.
On the Internet Protocol Version 4 (TCP/IPv4) Properties page enter IP information for an IP address in one of the private address space (10.x.x.x , 172.16.x.x or 192.168.x.x). Care should be taken when choosing your address that it is also not in the same address range as your work or home network settings.
Once you have entered the IP information click the OK button to continue. You will be taken back to the Properties page for the Local Area Connection, click the Close button to finalize the changes.
The last thing we need to do to complete this to add an entry to the hosts file. The hosts file in Windows can be found in
C:\Windows\System32\drivers\etc\. Back in the command prompt that was opened as the administrator bring up Notepad like below.
Add a line at the bottom that includes the IP address you added for the Loopback Adapter along with the name of the machine.
# Copyright (c) 1993-2009 Microsoft Corp. # # This is a sample HOSTS file used by Microsoft TCP/IP for Windows. # # This file contains the mappings of IP addresses to host names. Each # entry should be kept on an individual line. The IP address should # be placed in the first column followed by the corresponding host name. # The IP address and the host name should be separated by at least one # space. # # Additionally, comments (such as these) may be inserted on individual # lines or following the machine name denoted by a '#' symbol. # # For example: # # 18.104.22.168 rhino.acme.com # source server # 22.214.171.124 x.acme.com # x client host # localhost name resolution is handled within DNS itself. # 127.0.0.1 localhost # ::1 localhost 192.168.4.111 wrath.oracledistilled.com wrath
Once you are done, save and exit notepad. With all of that complete you should now be able to ping by name successfully.
C:\Windows\system32>ping wrath Pinging wrath.oracledistilled.com [192.168.4.111] with 32 bytes of data: Reply from 192.168.4.111: bytes=32 time<1ms TTL=128 Reply from 192.168.4.111: bytes=32 time<1ms TTL=128 Reply from 192.168.4.111: bytes=32 time<1ms TTL=128 Reply from 192.168.4.111: bytes=32 time<1ms TTL=128 Ping statistics for 192.168.4.111: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 0ms, Maximum = 0ms, Average = 0ms C:\Windows\system32>
Having the Loopback Adapter installed and configured on a machine that used DHCP prior to installing Oracle products will save you a lot of headache when the IP or host name of the machine changes when you change networks.