Oracle RAC Database Monitoring

Standard Installation

If you're not using Linux servers or want to install the plugin manually, follow the steps below.

Prerequisites

• Download and install the latest version of the Site24x7 Linux agent in the server where you plan to run the plugin.
• Python 3.7 or higher version should be installed.
• Install oracledb module for python

   pip3 install oracledb
  

Database User and Required Privileges

Create a dedicated Oracle RAC user for the RAC monitoring plugin and grant the required privileges.

CREATE USER {username} IDENTIFIED BY "{password}";

GRANT CREATE SESSION TO {username};

GRANT SELECT ON SYS.V_$PARAMETER TO {username};
GRANT SELECT ON SYS.V_$DATABASE TO {username};
GRANT SELECT ON SYS.V_$INSTANCE TO {username};

GRANT SELECT ON SYS.GV_$SYSMETRIC TO {username};
GRANT SELECT ON SYS.GV_$SYSSTAT TO {username};
GRANT SELECT ON SYS.GV_$STATNAME TO {username};
GRANT SELECT ON SYS.GV_$SYSTEM_EVENT TO {username};
GRANT SELECT ON SYS.GV_$INSTANCE TO {username};

Installation

• Create a directory named oracle_rac.

   mkdir oracle_rac
   cd oracle_rac/

• Install the oracledb python module.

   pip3 install oracledb

• Download the below files oracle_rac.cfg and oracle_rac.py place it under the oracle_rac directory.

   wget https://raw.githubusercontent.com/site24x7/plugins/master/oracle_rac/oracle_rac.py && sed -i "1s|^.*|#! $(which python3)|" oracle_rac.py
   wget https://raw.githubusercontent.com/site24x7/plugins/master/oracle_rac/oracle_rac.cfg

• Execute the below command with appropriate arguments to check for the valid json output:

    python3 oracle_rac.py --hostname "localhost" --port "1521" --sid "SID" --username "USERNAME" --password "PASSWORD" --oracle_home "ORACLE_HOME"

• After the above command with parameters gives the expected output, please configure the relevant parameters in the oracle_rac.cfg file.

   [RAC1]
   hostname = "localhost"
   port = "1521"
   sid = "ORCL"
   username = "oracle_rac_username"
   password = "oracle_rac_password"
   tls = "false"
   wallet_location = "/opt/oracle/product/19c/dbhome_1/network/admin/wallets"
   oracle_home = "/opt/oracle/product/19c/dbhome_1/"
  
   [RAC2]
   hostname = "localhost"
   port = "1521"
   sid = "ORCL"
   username = "oracle_rac_username"
   password = "oracle_rac_password"
   tls = "false"
   wallet_location = "/opt/oracle/product/19c/dbhome_1/network/admin/wallets"
   oracle_home = "/opt/oracle/product/19c/dbhome_1/"

Linux

• Place the oracle_rac under the Site24x7 Linux Agent plugin directory:

   mv oracle_rac /opt/site24x7/monagent/plugins

Windows

• Since it's a Python plugin, to run the plugin in a Windows server please follow the steps in this link. The remaining configuration steps are the same.

• Further, move the folder oracle_rac into the Site24x7 Windows Agent plugin directory:

   C:\Program Files (x86)\Site24x7\WinAgent\monitoring\Plugins\oracle_rac
  

The agent will automatically execute the plugin within five minutes and send performance data to the Site24x7 data center.

Supported Oracle RAC Metrics

Global Cache Metrics

Name	Description
GC CR Block Received Per Second	Number of consistent read blocks received per second from other RAC instances via Global Cache
GC Current Block Received Per Second	Number of current blocks received per second from other RAC instances
GC Average CR Get Time	Average time taken to retrieve consistent read blocks from another RAC instance
GC Average Current Get Time	Average time taken to retrieve current blocks from another RAC instance
GC CR Blocks Served Total	Total number of consistent read blocks served to other RAC instances
GC Current Blocks Served Total	Total number of current blocks served to other RAC instances
GC CR Block Received Total	Total number of consistent read blocks received from other instances
GC Current Block Received Total	Total number of current blocks received from other instances
Global Cache Blocks Lost	Number of blocks lost during interconnect transmission between RAC nodes
Global Cache Blocks Corrupted	Number of corrupted blocks detected during inter-instance communication

Global Cache Performance Metrics

Name	Description
Global Cache Average Block Receive Time	Average time required to receive blocks from other RAC instances
Global Cache Block Access Latency	Latency experienced when accessing blocks via the Global Cache
Global Cache Service Utilization	Total number of global cache blocks exchanged across RAC instances

GC Wait Analysis

Name	Description
GC CR Request Avg Wait Time	Average wait time for consistent read block requests
GC Current Request Avg Wait Time	Average wait time for current block requests
GC CR Block Busy Avg Wait Time	Average wait time when consistent read blocks are busy
GC Current Block Busy Avg Wait Time	Average wait time when current blocks are busy
GC Buffer Busy Acquire Avg Wait Time	Average wait time while acquiring global cache buffers
GC Buffer Busy Release Avg Wait Time	Average wait time while releasing global cache buffers
GC CR Request Wait Count	Total number of consistent read block request waits
GC Current Request Wait Count	Total number of current block request waits
GC CR Block Busy Wait Count	Number of waits due to busy consistent read blocks
GC Current Block Busy Wait Count	Number of waits due to busy current blocks
GC Buffer Busy Acquire Wait Count	Number of waits while acquiring global cache buffers
GC Buffer Busy Release Wait Count	Number of waits while releasing global cache buffers

RAC Interconnect Metrics

Name	Description
Interconnect Bytes Received Per Second	Amount of data received per second through the RAC interconnect
Interconnect Bytes Sent Per Second	Amount of data transmitted per second through the RAC interconnect

RAC Cluster Health Metrics

Name	Description
cluster_name	Name of the Oracle RAC cluster database
Active RAC Nodes	Number of active RAC instances in the cluster
RAC Nodes Down	Number of RAC nodes currently unavailable

RAC Node Discovery

Name	Description
RAC_Node_Details	Per-instance details including instance name, host name, instance number, and status