11 Replies Latest reply: Jan 15, 2014 3:22 AM by fb767351-a660-4b18-9a9f-73bc141f6a0c RSS

    Some dba and OS related confusions

    fb767351-a660-4b18-9a9f-73bc141f6a0c

      Hi All,

       

      I have few doubts related to database and OS perspective. Could pelase someone let remove my these doubts and clarify below questions:

       

      Qus1: Can we have two listener.ora file with same default port number 1521?

       

      Qus2: Why do we create two groups "dba" and "oinstall" while installing oracle database?

       

      Qus3: If my database is in archive log mode and in case archiver process is killed then redo will be archived or not otherwise what will happen?

       

      Qus4: If I have catalog database for RMAN metadata. And in case catalog database is crashed. Will I be able to use RMAN backupsets for restore the database?

       

      Qus5: What is needed to run "some_path/root.sh" script while installing the oracle database at last step?

       

      Qus6: How can we get to know what are the database running in my server from OS level itself means if any database is shutdown or crashed, can we get to know about those database from OS level itself? If yes then please specify the command?

       

      Qus7: How can we configure UDP protocol for my listener?

       

      Qus: If I am updating one table and update query is going on. Inbetween OS gets shutdown then when it is back my transaction will rolledback. Please let me know how it happenes means is there any process to do this or something else?

       

      Please clarify above questions.

       

       

      Regards,

      Michel

        • 1. Re: Some dba and OS related confusions
          rp0428
          Qus1: Can we have two listener.ora file with same default port number 1521?

          1. Your two sons, both named 'Bill' are in the living room playing

          2. You are outside

          3. You yell 'Bill come out here right now' through an open window.

          4. Which son should come outside to see what you want?

           

          Sometimes you just need to use common sense.

           

          When you post questions like the ones you posted you should also post what you think the answer is and why and ask if you are correct.

           

          Also post a link to the document or article (if there is one) where you got your information. The reason for that is that most people don't bother reading the Oracle documentation first. So BEFORE posting search the Oracle documentation.

          • 2. Re: Some dba and OS related confusions
            sb92075

            > So BEFORE posting search the Oracle documentation.

             

            which can be found at URL below

             

            Oracle Database Online Documentation 12c Release 1 (12.1)

            • 3. Re: Some dba and OS related confusions
              fb767351-a660-4b18-9a9f-73bc141f6a0c

              Hi rp0428/Sb,

               

              I do study oracle documents.I agree that first question I should not have asked. But rather than all question are senerio based so I thought I don't get those in oracle documentation.

               

               

              Regards,

              Michel

              • 4. Re: Some dba and OS related confusions
                JohnWatson

                fb767351-a660-4b18-9a9f-73bc141f6a0c wrote:

                 

                Hi All,

                 

                I have few doubts related to database and OS perspective. Could pelase someone let remove my these doubts and clarify below questions:

                 

                Qus1: Can we have two listener.ora file with same default port number 1521?

                 

                Qus2: Why do we create two groups "dba" and "oinstall" while installing oracle database?

                 

                Qus3: If my database is in archive log mode and in case archiver process is killed then redo will be archived or not otherwise what will happen?

                 

                Qus4: If I have catalog database for RMAN metadata. And in case catalog database is crashed. Will I be able to use RMAN backupsets for restore the database?

                 

                Qus5: What is needed to run "some_path/root.sh" script while installing the oracle database at last step?

                 

                Qus6: How can we get to know what are the database running in my server from OS level itself means if any database is shutdown or crashed, can we get to know about those database from OS level itself? If yes then please specify the command?

                 

                Qus7: How can we configure UDP protocol for my listener?

                 

                Qus: If I am updating one table and update query is going on. Inbetween OS gets shutdown then when it is back my transaction will rolledback. Please let me know how it happenes means is there any process to do this or something else?

                 

                Please clarify above questions.

                 

                 

                Regards,

                Michel

                Michel, you need to work on your learning technique. In the Oracle environment, "when in doubt - try it out". This applies to three of your questions:

                1. Try to start two listeners, listening on the same port and address. Then try different addresses.

                3. Kill the archiver process(es). You'll see the result soon enough.

                4. Again, test it.

                You also have some documentation questions:

                2. There is a chapter on this in the installation guide, though I suppose it is bit vague about "why". You need to think about the situation where you have several databases on one machine with different DBAs, and you need to restrict the DBAs' access to only their own DB.

                7. The Net Services Admin guide describes configuring the supported protocols.

                8. The Concepts Guide has  chapter describing the background processes which will answer this.

                That leaves two:

                5. I don't understand what you are asking.

                6. If I understand you correctly there is no definitive answer on Unix, though you can infer it from looking at various files such as oratab or the contents of your dbs directories. On Windows, look at the Windows services

                • 5. Re: Some dba and OS related confusions
                  fb767351-a660-4b18-9a9f-73bc141f6a0c

                  Hi John,

                   

                  Thanks for your indirect answers. This will make me learn more and for first three question definitely I will try as in practical.

                   

                  Regards,

                  Michel.

                  • 6. Re: Some dba and OS related confusions
                    rp0428
                    I do study oracle documents.I agree that first question I should not have asked.

                     

                    That isn't what I said. What I said was this:

                    When you post questions like the ones you posted you should also post what you think the answer is and why and ask if you are correct.

                    You can ask any question you need clarification about. But it is a big help when you tell us WHAT you think the answer is and WHY you think that:

                     

                    That lets us see if the reasons you are using make sense and what information you may be missing. It isn't going to help you if the only answer we can give you is YES or NO; you need to understand WHY the answer is correct as my example illustrated.

                    • 7. Re: Some dba and OS related confusions
                      cgswong

                      Q1: Can we have two listener.ora file with same default port number 1521?

                      A1. If on the same machine then only if they are listening on different virtual IPs, otherwise not on the same machine. As previously stated, you can try this out for yourself.

                       

                      Q2: Why do we create two groups "dba" and "oinstall" while installing oracle database?

                      A2. For role separation such that if you multiple software installations and/or databases on the same machine, all will have access to the central inventory owned by the primary "oinstall" group, while the other installations/databases can be owned by other secondary groups (i.e. "dba", "dba1", and so on). Taken a step further you can have different oracle software owners with the same primary "oinstall" group but different secondary groups.

                       

                      Q3: If my database is in archive log mode and in case archiver process is killed then redo will be archived or not otherwise what will happen?

                      A3. I like the idea of testing this out for yourself so I'll leave this to you ;-)

                       

                      Q4: If I have catalog database for RMAN metadata. And in case catalog database is crashed. Will I be able to use RMAN backupsets for restore the database?

                      A4. This depends on a few things but in the simplest case, assuming you have the control file, only need to recover a datafile, and the backup data is still available (as specified by the CONTROL_FILE_RECORD_KEEP_TIME parameter), then yes.

                       

                      Q5: What is needed to run "some_path/root.sh" script while installing the oracle database at last step?

                      A5. You must have access to the root account (directly or indirectly via sudo as an example) at the command line.

                       

                      Q6: How can we get to know what are the database running in my server from OS level itself means if any database is shutdown or crashed, can we get to know about those database from OS level itself? If yes then please specify the command?

                      A6. There are two different questions here, namely check for running databases, and check database status. To check for running databases from the OS there are some options, the most basic is likely the command:

                      ps -eaf | grep ora_pmon | grep -v grep

                       

                      The above checks for running processes, pipes that output through a 'grep' filter for commands having 'ora_pmon' (Oracle PMON process), which in turn is filtering out the command used to do the check itself (i.e. having 'grep' in the command).

                       

                      To check the status you'll need to scrap the alert log file for certain strings. You could also use 'srvctl status database -d <dbname>' if that is available, but it will only give online/offline status.

                       

                      Q7: How can we configure UDP protocol for my listener?

                      A7. Don't worry about this, it's taken care of auto-magically. Read the Oracle networking documentation for information.

                       

                      Q8: If I am updating one table and update query is going on, in between OS gets shutdown then when it is back my transaction will be rolled back. Please let me know how it happens meaning is there any process to do this or something else?

                      A9. There's nothing that you need to do, it's handled internally by the database. I highly recommend reading through the concepts documentation for full understanding of this, as well as how things generally work inside the Oracle database.

                       

                      Hope this helps.

                      • 8. Re: Some dba and OS related confusions
                        jgarry

                        fb767351-a660-4b18-9a9f-73bc141f6a0c wrote:

                         

                        Hi rp0428/Sb,

                         

                        I do study oracle documents.I agree that first question I should not have asked. But rather than all question are senerio based so I thought I don't get those in oracle documentation.

                         

                         

                        Regards,

                        Michel

                        So, this is homework or interview?  Nothing wrong with asking those questions as long as you are clear about it.  But you are best served being guided through how to answer them rather than being given the answer.

                        • 9. Re: Some dba and OS related confusions
                          fb767351-a660-4b18-9a9f-73bc141f6a0c

                          Hi Jgarry,

                           

                          Its all related to interview

                           

                          Regards,

                          Michel

                          • 10. Re: Some dba and OS related confusions
                            fb767351-a660-4b18-9a9f-73bc141f6a0c

                            Defintely Sir I'll take care henceforth.

                            • 11. Re: Some dba and OS related confusions
                              fb767351-a660-4b18-9a9f-73bc141f6a0c

                              Thanks a lot Cgswong for providing those answers.