7 Replies Latest reply on Mar 9, 2018 8:06 PM by gmichaud-verreault

    Network configuration for PI Servers

    flost

      Helo together,

       

      I´m thinking about different ways how to handle Server Name and IP-Address for PI Servers. The current reason is beginning of planning for my next upgrade (hardware, OS and PI applications) of my PI Servers. The background is to minimise the Impact on data collection and data retrieval while an upgrade happens. In my case there is no collective so I do not take this into account.

       

      Due to my knowledge there are two common ways to do an upgrade:

       

      1) Setting up new Servers with new Server Names and IP Adress. In the first step the same versions of the PI applications like on the legacy Servesr will be installed. After data move the applcaitons will be updated. After this the Interface nodes Need to be reconfigured to send the data to the new PI Data Archive Server. Clients also need to be reconfigured to retrieve the data from the new Servers (from Data Archive as well as from AF-Server).

      2) Shutting down the old Servers and installing the new Servers with the same Server Names and same IP-Adresses. In the first step the same versions of PI applications like on the legacy Servers will be installed. After data move the applications will be updated. In this case the clients and Interface nodes do not need to be reconfigured.

       

      So far nothing new. there are some points to be considered for these ways:

       

      1) The buffer queues on Interface nodes are dedicated for an PI Data Archive Server. If you change the PI Server for buffering a new buffer queue is beeing generated. The data insinde the old buffer queue will not be delivered to the new PI Server. This means that you have to carefully plan the configuration switch to avoid data loss. If you have redundand Interfaces it is more complicated.

      2) While installing and the update process there is no access to the data. In Addition you have to make sure that the new Server will have the same PI Server ID as the old Server had. It could also be an problem with Network routing or other IT related topics when there are different servers with the same name and IP Adress (e.g. it is not possible to have the same name and IP-Adress in the Network).

       

      The last times we did an upgrade we used way 1. Im currently trying to evaluate a new way. Therfor I hope for hints and comments from you:

       

      My idea is to create an DNS alias for my PI Servers. The alias would be pointing to the current Server name. In case of an upgrade I would prepare the new Server. When it is finished I would change the DNS Alias. So no configuration chage should be nessesary on clients and Interface nodes.

      I need more information about the PI Server IDs in this Scenario. There is some additional study of the administration guides nessesary.

       

      Are there any hints or comments for this Scenario? Anything that I did not take into acount? Any experiances with this apporach? How do you handle this when you do an upgrade?

       

      Kind Regards

       

      Florian

        • Re: Network configuration for PI Servers
          Steve Boyko

          Typically we install the same version of PI on a new server, with a new name and new IP address, with a backup of the current server's configuration and data. Once that is working, we do the cut-over.

           

          At cut-over, the old server is shut down, data and configuration copied over again to the new server. The old server gets a temporary IP address and the new server gets the old server's IP address. Either DNS aliasing is used or the new server is renamed to the old server's name.

           

          The procedure to retain the server ID on a move is documented here:

          to share Copy https://livelibrary.osisoft.com/LiveLibrary/content/en/server-v10/GUID-1BF18FBA-C9B2-4CC7-AF24-338C2B920FE9

           

          This article talks about changing server IP addresses and how it affects interfaces:

          https://techsupport.osisoft.com/Troubleshooting/KB/3282OSI8

          5 of 5 people found this helpful
            • Re: Network configuration for PI Servers
              flost

              Hi Steve,

               

              sounds good. Thank you for the two links. It is good to know where to look.

               

              If my knowledge is right the interfaces will start buffering at the moment when you shut down the old Server. After renaming the new one the interfaces will connect to the new Server and will start sending the buffered data. I will take this method into account for my planning.

               

              I have an additional question: At which state do you update the new Server to the new version? Bevor or after the Interfaces send data to the new Server?

               

              Kind regrads

               

              Florian

                • Re: Network configuration for PI Servers
                  Steve Boyko

                  I always upgrade after the interfaces resuming sending data. I like to do only one change at a time, so that if things go awry, I have an idea why.

                  1 of 1 people found this helpful
                    • Re: Network configuration for PI Servers
                      flost

                      Fully agree. Thank you for clarifying.

                        • Re: Network configuration for PI Servers
                          gmichaud-verreault

                          I would also highly suggest isolating the machines (firewall, disable the NIC, etc.) before doing any of this. I have seem customers create a new server and seeing the data being dumped before the backup is restored causing data loss too many times.

                           

                          My usual rough plan is (assuming a move and upgrade):

                          • Go through all the interfaces / connectors / custom app and make sure that buffering is enabled and in a good state
                          • Isolate the new and old server from the network
                          • Take a backup and move to the new server
                          • Upgrade the new server (As Steve mention, if there are a lot of custom apps in play, I may skip this step and perform it later)
                          • Rename / Re-IP the old server, then rename / re-IP the new one to the previous name/ip
                          • Do a healthcheck of the PI Data Archive and look at the tuning parameters / file structure
                          • Take the new server back on the network (disable firewall, re-enable NIC card, etc.)

                           

                          Gabriel

                          1 of 1 people found this helpful
                  • Re: Network configuration for PI Servers
                    rbeadle

                    When I last did an upgrade it was a requirement for us to both rename and change the IP address to meet the requirements of a merger. So option one choose us. I actually like option one; it allowed us to set a new DA server restore a most recent backup and have a fully working DA server with very little interruption on the production side(in parallel ). Once the DA server was fully in place, we redirected the interface nodes from the old DA server to the new DA server. We then redirected the clients to consume data from the new data archive  (it was also important for us to use the PI Firewall to prevent users from writing to the old DA server once the interfaces were reconfigured).

                     

                    We then use the PI-to-PI interface between the old server and the new server to back-fill the gap between the last backup and  the time of the interface switch.