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hello and welcome to the SAP system administration video training system administration also known as basis for people who are experienced in this covers the installation maintenance and the day-to-day running of live ASAP implementation in this session we are going to talk about the architecture of an a web application server a based ASAP system and then we’ll discuss what is an instance what are processes and what would you need to do on a daily basis while working as a system administrator so this is the system architecture diagram and various possibilities the single tiers landscape is not shown here because that is typically a mainframe processing scenario where all the processing tasks including database application and presentation processes are performed by just one computer tooth here is what s if we started with essentially a two-tier configuration is implemented using special presentation servers that are responsible only for formatting the graphical interface then SP has evolved into the well known r3 which is essentially a three-tier configuration wherein each layer runs on its own host and many different application servers can simultaneously work with the data of a database server moving on to the world of the internet the three-tier has now evolved into a multi tier system landscape we will talk more about the multi tier landscape in subsequent slides one of the most important concepts in the ASAP system admin is the concept of an instance so what is an instance an instance is an admin unit that combines ASAP system components providing one or more services the services provided by an instance are started or stopped together at the same time you can use a common instance profile to set parameters of all the components of an instant at one go also to be noted is that each instance has its own buffer areas an instance runs on one physical computer but there can be multiple instances on one computer itself usually an instance is identified by the system ID the so-called Sid s ID and the instance number so for example for this training we are going to be using the ID system so this is my ID system here and if I go to change item I can see my system number is 0-2 and this ESA is my system ID these two together determine my instance to which I will log on to during the training for those of you already experienced in system admin you would know that the term SAP instance and application server are often used synonymously so essentially an app server is a SAP instance the central instance of an SP system is is a special one because it provides services that no other instance of the system offers so for example for application server a bap these are these services would be a message messaging services and NQ work processes messaging and NQ services are only provided by a central instance we’ll study more about the kind of processes and services in subsequent slides so this slide shows us an overview of application server a BAP work processes and services services are essentially used for internal or external communications so for example

the message server here handles communications between the distributed dispatchers within the a si bap thereby enabling scalability of several parallel application servers the message server is configured only once for si P system as we saw in the previous slide is the central instance that has the a web message server the Gateway reader enables communication within SP systems or it can also enable communication between an SP system and an external application system there is only ever one Gateway for dispatcher the internet communication manager also known as ICM enables internet communication between an SP system and web protocols such as HTTP the ICM receives requests from the clients and forwards them to the ASAP system for processing and it does a lot of other clever things like it recognizes whether the request is a call for application server a vApp or application server Java and then after deciding it forwards the request accordingly it can also direct HTTP requests from an SCP system to a web server and send the response back to the ASAP system so these three services are not work processes but services typically provided by a central instance then you have the so called evap dispatcher it essentially distributes the requests that it gets from the services maybe Y egg to the external world on two different work processes now maintenance and setting up of different work processes is one of the key system admins activity so let’s have a close look at some of these so this is the dialog work process essentially when a user interacts on a screen or a GUI screen or a web screen it consumes the request goes to a dialog work process every dispatcher requires at least two dialog work processes then you have the spool process which is used for printing at least one spool work process is required for each SP system but it’s possible to configure more than one depending on your printing requirements then you have this update processes they execute the update requests you need at least one update work process per se B system but more than one can be configured background processes typically used for running bad jobs and reports that consume a lot of resources and these processes run without any interaction with the user you need at least two background processes for each SP system but more can be configured Lock Management again we discussed this this is the NQ work process that’s where the EE here again this work process is only on the central instance like we discussed before the N key work process essentially administers the lock table in the shared memory the lock table contains the logical database locks of the a vibrant time environment and only 1nq work process is needed per system so let’s look at these processes in the system itself so I’ve logged on to my IDs so I log in and if I go to transaction sf50 I can see my various work processes that we’ve just discussed so the server that I’m working on has five dialogue processes zero to four one update one and Q and then again one dialogue so

that makes it six three background processes one spool and this is a different kind of an update process and we’ll talk about it later more in the training now me as a user in this session should be represented by a dialog work process because all user interactions go to a dialog work process and the mere fact that I have this screen open in front of you means I’m consuming one dialogue process so let’s see let me highlight this and go back and see yes it’s a dialogue process with this internally generated number state is running because I’m on the screen and this is the standard program that is generating this screen that you see here this is my client and this is my user ID that I logged on with let us have a look at some of the important transactions that you would be dealing with on a daily basis when you work as a system admin so the first one is sm 0 4 or l 0 8 sm 0 4 essentially displays all the users logged on to the local instance and various admin functions are possible like logging off a user or displaying an overview of the user’s memory consumption etc so let’s have a quick look at this transaction sm 0 for so my system that I’m logged onto this only another user uses zero nine and user 0-7 is myself this is my terminal currently I’m not in any transaction on my local server this is the time how many sessions and whether it’s Glee background or a web so if I go to this tab I can set in a tracing information to find what exactly I’m doing how much memory I’m consuming I can log the user off from either this instance or system-wide and so on and so forth The Associated transaction a l08 provides very similar functionality with the difference being you cannot do any editing transaction SM 51 displays all instances that are currently active in your SP system and you cannot only access numerous other transactions from here but also execute them for a specific app server that you select so let’s have a quick look at SN 51 here of on the system there is only one server and if I go to server name administration I’ll do this again so you can see it clearly on the screen you have various things like you can shut down the server hard shut down soft shutdown deactivate or activate trees now I should be able to see it more clearly the different options you have here transaction SM 37 provides an overview of background jobs that are either plan or have already been executed and you can select these jobs and see how much time it took to execute and the report that resulted as a at the end of the background job etc so let’s have a quick look at this transaction as I’m 37 this is my user so let me see all my jobs no job I haven’t selected any job but if I put a star here and execute this again let’s see what we find might take a couple of seconds for the system to read all the jobs by all the users within this selected set of dates so here is my result list I can see the

different jobs set by different users and the status the start time the end time the duration the delay as in you might kick off the job immediately but it may not actually start immediately because there are no work processes available so there is usually a delay the name of the job the user who created it the next transaction as some 50 is what we saw previously it gives you how many work processes you have and which of these are busy so for example if you have too few dialogue processes a lot of them would be in the running status and there will not be any in the waiting status which means that if a user logs on and there is no dialogue process available he’ll just simply be innovating status you’ll see that circle which means the system is trying to do something but cannot quite so the user has to wait and that would imply you need more dialogue processes so this is a very useful transaction for day-to-day monitoring of the system and making sure you have enough processes under various categories to cater of all the things the system needs to do and all the users that need to use the system then you have transaction SM 12 which is used to monitor log entries a log table is normally managed by the NQ work process which is used for locking so that two users cannot make a change in the same table at the same time however in exceptional cases as a system admin you may need to delete the lock entry but that should be done only – careful consideration so looking at the system let me go to transaction SM 12 and this is my user so if I try to list the LA countries at the moment there are none but if I were in a different session to open up some customizing so maintain as the condition types and then go back to my original locking session and I run the same thing again I hope to get some locked entries because in this other session I have this open in change change mode so let’s give it a go I run my transaction again and here user 7 is locking several tables and now when I exit my other screen and then run the transaction again refresh this all the locks have disappeared transaction su 0 1 used for individual user maintenance so this is my transaction su zero one and the same screen that we were on previously so if I look at it I can see different elements of information language mobile phone etc but the most important thing here is the roles and authorization so if I expand this I can see these are the roles i have typically I would not expect the user to have SAP all and SAP new because this pretty much means you can do anything on the system but since this is an ID system I’ve got these profiles however if you want to do mass maintenance of users multiple users then transaction su 10 is what you need to use transaction SM 13 allows you to make sure that the update processes have run smoothly so for example if problems occur they are logged in this transaction and you can analyze them here however one caveat you need to watch that if you use this transaction to view any data the data may be of a sensitive nature for example a salary increase for the employees of a company then the system will log the fact that you’ve actually seen the data

so to be treated with caution and then you have SM 51 which is used to analyze various system messages that might be generated due to errors or communication issues with other systems so on and so forth the entries are color coded so you can easily spot the red entries and analyze and fix the errors so we have a quick look at SM 21 this is the kind of output I get so various color coded entries that I can investigate further when you have transaction sm0 – which is used for sending system messages for example if there is an important announcement if the system is going down for half an hour you can send a message to all the users on the system that the system is going down and they should save the work or something similar you can also specify an expiry date for a message you can specify whether the message is system-wide or for a specific system and so on so for example let us try to create a new system message sm0 – we already have this message existing so when somebody logs on they will see this but let me just create a new message helloworld this is going to be issued on anybody on this server and the expire starts today and expires in a month time so system message is added now if I go back or do any interaction with the system I get the message helloworld issued by this user then we move on to transaction our Z 20 and this essentially is like monitoring cockpit for the entire system it is possible to not only monitor multiple systems by RFC connections but you can also monitor systems with all releases that are still within the maintenance period of si P it can create your own views that only display the parameters you need for a specific user group and these individual views are also known as monitors the values displayed for the attributes that you are monitoring can be set using threshold values and then a warning can be for example displayed as a yellow or as a problem in color red you can also set automatic reaction so when the threshold specified is reached then a predefined reaction is triggered so let’s have a quick look at this our Z 20 so this is the kind of output I get to start with now this pretty much covers all the the whole system so if I look at SQL Server monitor I can see different you can see various parameters like disk free space the growth etc etc so we hope you enjoyed this session and hope to see you again soon thank you

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