Oracle RAC Uptime Test

In most production environments, it is essential to monitor the uptime of critical servers in the infrastructure. By tracking the uptime of each of the servers, administrators can determine what percentage of time a server has been up. Comparing this value with service level targets, administrators can determine the most trouble-prone areas of the infrastructure.

In some environments, administrators may schedule periodic reboots of their servers. By knowing that a specific server has been up for an unusually long time, an administrator may come to know that the scheduled reboot task is not working on a server.

The Oracle RAC Uptime Test monitors the uptime of every node in an Oracle cluster.

Target of the test : Oracle Cluster

Agent deploying the test : An internal agent

Outputs of the test : One set of results for each node in the Oracle cluster being monitored

Configurable parameters for the test
  1. TEST PERIOD - How often should the test be executed
  2. Host – The host for which the test is to be configured
  3. Port - The port on which the server is listening
  4. orasid - The variable name of the oracle instance

  5. service name - A ServiceName exists for the entire Oracle RAC system. When clients connect to an Oracle cluster using the ServiceName, then the cluster routes the request to any available database instance in the cluster. By default, the service name is set to none. In this case, the test connects to the cluster using the orasid and pulls out the metrics from that database instance which corresponds to that orasid. If a valid service name is specified instead, then, the test will connect to the cluster using that service name, and will be able to pull out metrics from any available database instance in the cluster.

    To know the ServiceName of a cluster, execute the following query on any node in the target cluster:

    select name, value from v$parameter where name =’service_names’

  6. User – In order to monitor an Oracle RAC, a special database user account has to be User – In order to monitor an Oracle database server, a special database user account has to be created in every Oracle database instance that requires monitoring. A Click here hyperlink is available in the test configuration page, using which a new oracle database user can be created. Alternatively, you can manually create the special database user. When doing so, ensure that this user is vested with the select_catalog_role and create session privileges.

    The sample script we recommend for user creation (in Oracle database server versions before 12c) for eG monitoring is:

    create user oraeg identified by oraeg create role oratest;

    grant create session to oratest;

    grant select_catalog_role to oratest;

    grant oratest to oraeg;

    The sample script we recommend for user creation (in Oracle database server 12c) for eG monitoring is:

    alter session set container=<Oracle_service_name>;

    create user <user_name>identified by <user_password> container=current default tablespace <name_of_default_tablespace> temporary tablespace <name_of_temporary_tablespace>;

    Grant create session to <user_name>;                                 

    Grant select_catalog_role to <user_name>;

    The name of this user has to be specified here.

  7. Password – Password of the specified database user
  8. Confirm password – Confirm the password by retyping it here.
  9. REPORTMANAGERTIME – By default, this flag is set to Yes, indicating that, by default, the detailed diagnosis of this test, if enabled, will report the shutdown and reboot times of the device in the manager’s time zone. If this flag is set to No, then the shutdown and reboot times are shown in the time zone of the system where the agent is running (i.e., the system being managed for agent-based monitoring, and the system on which the remote agent is running - for agentless monitoring).
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Has Oracle server been restarted?:

Indicates whether this node has been rebooted during the last measurement period or not.

Boolean

If this measure shows 1, it means that the node was rebooted during the last measurement period. By checking the time periods when this metric changes from 0 to 1, an administrator can determine the times when this node was rebooted.  The detailed diagnosis of this measure, if enabled, indicates the date/time at which the node was shutdown, the date on which it was restarted, the duration of the shutdown, and whether the node was shutdown as part of a maintenance outine. 

Uptime since the last measurement:

Indicates the time period that this node has been up since the last time this test ran.

Secs

If the node has not been rebooted during the last measurement period and the agent has been running continuously, this value will be equal to the measurement period. If the node was rebooted during the last measurement period, this value will be less than the measurement period of the test. For example, if the measurement period is 300 secs, and if the node was rebooted 120 secs back, this metric will report a value of 120 seconds.  The accuracy of this metric is dependent on the measurement period – the smaller the measurement period, greater the accuracy.

Uptime:

Indicates the total time that the node has been up since its last reboot.

Mins

Administrators may wish to be alerted if a node has been running without a reboot for a very long period. Setting a threshold for this metric allows administrators to determine such conditions.