9 Replies Latest reply: Mar 21, 2013 10:53 AM by sb92075 RSS

    tnsnames or OID

    997007
      I'm considering the use of tnsnames for simplicity of installation and ease of maintenance in my environment, rather than staying with OID. There are about 300 desktops, and 6 Oracle servers to maintain with oracle connections to the IIS webserver on the Microsoft platforms.
      The IIS admin tells me when I change tnsnames, IIS has to be rebooted since it doesn't recognize the connection string changes in the tnsnames update. I've never seen this
      type of problem before, does anyone have experience with using tnsnames for connection to the IIS server and if any parameters, connection pools, or config has to be done on
      the IIS side to allow for changes to the tnsnames file?
      Thanks in advance,
      Kim
        • 1. Re: tnsnames or OID
          sb92075
          994004 wrote:
          I'm considering the use of tnsnames for simplicity of installation and ease of maintenance in my environment, rather than staying with OID. There are about 300 desktops, and 6 Oracle servers to maintain with oracle connections to the IIS webserver on the Microsoft platforms.
          The IIS admin tells me when I change tnsnames, IIS has to be rebooted since it doesn't recognize the connection string changes in the tnsnames update. I've never seen this
          type of problem before, does anyone have experience with using tnsnames for connection to the IIS server and if any parameters, connection pools, or config has to be done on
          the IIS side to allow for changes to the tnsnames file?
          Thanks in advance,
          Kim
          why do you post question regarding IIS behavior in this Oracle forum?
          • 2. Re: tnsnames or OID
            JustinCave
            994004 wrote:
            I'm considering the use of tnsnames for simplicity of installation and ease of maintenance in my environment, rather than staying with OID. There are about 300 desktops, and 6 Oracle servers to maintain with oracle connections to the IIS webserver on the Microsoft platforms.
            How does putting a tnsnames.ora file on 300 desktops along with pushing changed versions of the file to all 300 desktops simplify installation and ease maintenance over a centralized OID repository? That's a bit like saying that you want to move toward maintaining /etc/hosts files on every machine rather than using DNS to resolve a host name to an IP address.

            Justin
            • 3. Re: tnsnames or OID
              TSharma-Oracle
              How does putting a tnsnames.ora file on 300 desktops along with pushing changed versions of the file to all 300 desktops simplify installation and ease maintenance over a centralized OID repository? That's a bit like saying that you want to move toward maintaining /etc/hosts files on every machine rather than using DNS to resolve a host name to an IP address.
              Justin, He has all Windows environment. He can make a centarlized network drive and map it to every desktop and server which is a piece of cake for system admins.

              I do agree with you in case of multiple OS environments.
              • 4. Re: tnsnames or OID
                JustinCave
                But even if we assume that all machines are Windows boxes, that they all successfully mount the network drive every single time, etc. this configuration is, at best, no better than the OID configuration. And that assumes that the intention is to have a centralized file which is not always what organizations really do. If you've already got OID working, I'm hard-pressed to envision why you'd ever want to move to using local naming. I can imagine situations where local naming is sufficient so that it makes no sense to invest the time to get OID up and running and convert over to OID. I can't see why you'd want to go back.

                Justin
                • 5. Re: tnsnames or OID
                  TSharma-Oracle
                  I second you on this.
                  • 6. Re: tnsnames or OID
                    997007
                    It's the case that OID usage is diminishing while tnsnames has always been a standard connection technology. A consistent tnsnames file may be pushed out quite easily of use of a common share would work.
                    I'm still asking if anyone knows of a reason for a connection problem to the web server if a change were made in tnsnames and the webserver was not rebooted causing a short down time ?
                    Thanks for your responses.
                    • 7. Re: tnsnames or OID
                      JustinCave
                      Is there a reason that you don't test the IIS portion of your question in your environment (presumably in dev)? I'm pretty sure that IIS itself has no idea what a tnsnames.ora file is and, therefore, isn't caching anything. Your application, however, could well be. Most three-tier applications are going to have a connection pool, those connections will be opened when the application starts (using the old TNS entry). At a minimum, for most three-tier applications, you'd need to dump the connection pool and the easiest way to do this is generally to reboot the application server. This has nothing to do with Oracle and everything to do with your application.

                      Justin
                      • 8. Re: tnsnames or OID
                        sb92075
                        994004 wrote:
                        It's the case that OID usage is diminishing while tnsnames has always been a standard connection technology. A consistent tnsnames file may be pushed out quite easily of use of a common share would work.
                        I'm still asking if anyone knows of a reason for a connection problem to the web server if a change were made in tnsnames and the webserver was not rebooted causing a short down time ?
                        Thanks for your responses.
                        I suspect that IIS, like similar software, reads tnsnames.ora only when it starts.
                        tnsnames.ora, like any text file, is static.
                        It would be wasteful for IIS, or similar software, to re-read tnsnames.ora file for every access to the DB.
                        If & when, tnsnames.ora is changed, then IIS is oblivious to the change until after the next restart of IIS.
                        • 9. Re: tnsnames or OID
                          TSharma-Oracle
                          The answer to your question is it depends upon the application configuration. Some application like .net applications reads tnsnames.ora entry and save this information in the memory. So if you change this information , your application needs to read this entry again and load it into a cache. BUT BUT I don't think you need to reboot the IIS for this. You can just flush and load the 'application pool' whch takes less than 3 seconds in normal environments. But yes you do need to reload that tnsnames.ora into the memory if application is designed that way.