Retail Pro 9 Loopback Adapter Installation and Explanation

It has been found that creating a loopback adapter is necessary in some cases. The reason needed for a loopback adapter is because of DHCP configurations, Off-Network installs, and Wireless Network Adapters.

We have seen in cases where the Retail Pro 9 installation can fail. The reason why the failure took place could be indicated in the following log file.

C:\Program Files\RetailPro9\Rpro9Install.LOG

In the following log file entries you can see the failure took place because of the inability to create the TNSListener service. This is in direct relation to not have having a loopback adapter installed.

Here is an example of a good log file.

7-25-2011 : 14:59:06 | Ora11g_CreateListener: Starting
7-25-2011 : 14:59:06 | Ora11g_CreateListener: NetcaExe : D:\Oracle\ODS11gr1\bin\netca.bat
7-25-2011 : 14:59:06 | Ora11g_CreateListener:NetcaRsp : D:\RetailPro9\OraTmp\netca.rsp
7-25-2011 : 14:59:06 | Ora11g_CreateListener:NetcaCmdline : /silent /responseFile "D:\RetailPro9\OraTmp\netca.rsp"
7-25-2011 : 14:59:06 | Modification by adding cmd.exe
7-25-2011 : 14:59:06 | Ora11g_CreateListener NetcaExe : CMD.EXE
7-25-2011 : 14:59:06 | Ora11g_CreateListener:NetcaCmdline :� /C D:\Oracle\ODS11gr1\bin\netca.bat /silent /responseFile "D:\RetailPro9\OraTmp\netca.rsp"
7-25-2011 : 14:59:33 | Ora11g_WaitForService:Starting
7-25-2011 : 14:59:48 | Ora11g_WaitForService:Ending
7-25-2011 : 14:59:48 | Ora11g_CreateListener:Ending

Here is an example of a bad log file.

10-29-2009 : 16:32:02 | Ora11g_CreateListener:Starting
10-29-2009 : 16:32:02 | Ora11g_CreateListener:NetcaExe : C:\Oracle\ODS11gr1\bin\netca.bat
10-29-2009 : 16:32:02 | Ora11g_CreateListener:NetcaRsp : C:\WINDOWS\\OraTmp\netca.rsp
10-29-2009 : 16:32:02 | Ora11g_CreateListener:NetcaCmdline : /silent /responseFile "C:\WINDOWS\\OraTmp\netca.rsp"
10-29-2009 : 16:32:12 | Ora11g_CreateListener:Service Does not exist : OracleODS11gr1TNSListener
10-29-2009 : 16:32:12 | Ora11g_WaitForService:Starting
10-29-2009 : 16:32:12 | Ora11g_WaitForService:OracleODS11gr1TNSListener : Service does not exist
10-29-2009 : 16:32:12 | Ora11g_CreateListener:Service Will not start : OracleODS11gr1TNSListener
10-29-2009 : 16:32:12 | Ora11g_CreateListener:Ending
10-29-2009 : 16:32:12 | Ora11g_InstallProc:Ora11g_CreateListener FAILED
10-29-2009 : 16:32:12 | The Database has failed to install, aborting installation.� Please contact your support department.

Typically the need for a loopback adapter can be found in two ways. You can have a failed attempt at installing the Retail Pro 9 application. This reason for failure would be indicated in the log file above. The second reason would be indicated in unexplained disconnections from the Retail Pro 9 application. These disconnections would occur during usage of the Retail Pro 9 app. The common problems are DHCP configuration, Wireless Network Adapters and Off-Network installs.

The issue is that on the DHCP server end, things can be configured to:

a. dynamically assign an IP address from a pool of IP's
b. dynamically assign an IP address/hostname from a pool of IP's and hostnames.

Most DHCP servers associate each IP address in the pool with a hostname in DNS. Thus, depending on how the hostname is retrieved, you may get the local Windows Machine Name (set by setting the machine name in the control panel) or you may get the DHCP assigned hostname (retrieved from DNS). What ends up happening is that you get a mixture of hostnames and IP addresses embedded in configuration files, and the DB control doesn't start.

The same thing would happen if you were to do an off-network install. When you are off-network, you would get the local machine name returned whenever a query to get the hostname is done. If you were to connect this to the network after the fact, then the servers would not start because the runtime calls to get the hostname would not match the off-network config-time call for the hostname which was embedded in multiple configuration files and directory names.

It is necessary for RetailPro9 to have a consistent connection to the Oracle install for data integrity and session consistency. We have found that this is especially necessary when RetailPro9 is installed on a laptop machine. In most cases the laptop has a Wireless Network Adapter. It's possible that this Wireless Network Adapter is the primary adapter, dependent on which order the network adapters were installed. In this case the Wireless Network Adapter becomes the primary network adapter and thus becoming the network adapter that Oracle uses to maintain the network connection. This can become a problem due to the nature of wireless networks and their inability to maintain a connection. This creates an unstable environment for RetailPro9. A loopback adapter is needed in this case.

When you install a loopback adapter, the loopback adapter assigns a local IP address for your computer. After you install a loopback adapter on your computer, you have at least two network adapters on your computer: your own network adapter and the loopback adapter. RetailPro9?s database needs to have Windows using the loopback adapter as the primary adapter in cases where DHCP and Wireless networks are involved.

The primary adapter is determined by the order in which you installed the adapters: it is the last adapter installed. If you install additional network adapters after you install the loopback adapter, you need to un-install the loopback adapter and re-install it.

Below you will find a link to the Oracle Knowledge Base that covers installation and removal of loopback adapters for a series of Windows installs. Included are discussions on the loopback adapters functionality and when it is necessary.

http://download.oracle.com/docs/cd/B19306_01/install.102/b14316/reqs.htm#BABGCEAI