We basically have four options for managing a database. If we have a small number of databases we might look at using the sqlplus sysdba command line access and grind through administration. We also have a database monitor that is installed by default with the database cloud service. We can dive into this database through the monitor and look at log running queries, tablespace sizes, and generic utilization. We can also connect with sql developer and look at the new DBA interfaces that were added in the latest release in early 2016. The fourth and final way of administering is to look at commercial management tools like Oracle Enterprise Manager (OEM) or other tools that aggregate multiple systems and servers and give you exposure beyond just the database. These commercial tools allow you to look at they layer that you are most interested in. You can get a PeopleSoft Management Pack for OEM that allows you to look at purchase order flow, or payroll requests. You can get diagnostics and tuning packs for the application server and database that allows you to look at what part of the PeopleSoft implementation is taking the longest. Is it the network connection? It is a poorly tuned Java Virtual Machine that is memory thrashing? It is a sql statement that is waiting on a lock? Is it a storage spindle that is getting hammered from another application? Is it a run away process on your database server that is consuming all of the resources? All of these questions can be answered with a monitoring tool if you not only know how to use it but what is available for free and what you need to purchase to get the richer and more valuable information.
To get to the database monitor we go to the cloud services console (which changed over the weekend so it looks a little different), click on database, click on Service Console, and click on the database name.
If we click on the dbaas_monitor menu item in the hamburger menu system to the right of the service name it might fail to connect the first time. It will take the ip address of the database and try to open https://ip address/dbaas_monitor. We first need to open up port 443 to be able to communicate to this service.
To get to the network connection we need to go to the Compute Service Monitor, click on the Network tab, and change the proper port number for our server prs12cHP. If we hover over the labels on the left we see what ports we are looking for. We are specifically interested in the https protocol. If we click on the hamburger menu next to this line item we can Update the security list which pops up a new window.
To enable this protocol we enable the service and click the Update button. Once we do this we can retry the dbaas_monitor web page. We should expect a security exception the first time and need to add an exception. We login as dbaas_monitor and the password that we entered in the bottom left of the screen for the system passwords when we created the database.
At this point we can look at cpu utilization, table space usage, if the database is running, and all other monitoring capabilities. Below are the screen shots for the listener and the table sizes and storage by pluggable database.
We can look a little deeper at things like alerts, wait times, and real time sql monitoring. These are all available through command line but providing a service like this allows junior database administrators to look at stuff quickly and easily.
The biggest drawback to this system is that you get a short snapshot and not a long term historic archive of this data. If we use Enterprise Manager, which we will look at in a later blog, from a central site we collect the data in a local repository we can look back at months old data rather than live or data from the past few hours.
In summary, if we use platform as a service, we get tooling and reporting tools integrated into services rather than having to spin these up or look at everything from the command line as is done with infrastructure as a service. We get other features but we are diving into database monitoring this week. We briefly touched on database monitoring through what was historically called dbmonitor and is moving towards dbaas_monitor or a central enterprise manager pane of glass for database services in our data center and in the cloud. One of the key differentials from Oracle Database as a Service and Amazon RDS is database monitoring. We will look at database monitoring for Amazon RDS later this week and notice there are significant differences.