| Oracle SNMP Support Reference Guide
This chapter covers the following topics:
This manual documents four Oracle products that provide SNMP support. These products are:
The Oracle Servers (Oracle7 and Oracle8) are the relational database management systems (RDBMS) developed and sold by Oracle Corporation. These RDBMS include the database that stores information, as well as the server software that accesses and manipulates that information.
For more information about Oracle Server, see the Oracle Server Concepts manual specific to your system.
The Listener is a protocol-independent application listener that receives connections on behalf of applications running over a variety of underlying protocols. The Listener is a component of SQL*Net, Oracle's remote data access product, enabling client/server and server/server communications across any network. It runs as a single process or task.
For more information about the Listener, see the manual Understanding SQL*Net.
Oracle Names is a product that provides a directory service, by making database address and database link information available to all nodes throughout the network.
For more information about Oracle Names, see the manual Oracle Names Administrator's Guide.
Oracle Enterprise Manager provides Oracle database administrators with an intuitive, easy-to-use interface and a high degree of automation through remote task execution and reactive and proactive management capabilities. It also scales to accommodate both very large database configurations, while being flexible enough to handle installations with many databases. Oracle Enterprise Manager includes an open-architecture design, providing third-party vendors and customers with the ability to integrate their applications into Oracle Corporation's system management platform.
Six MIBs support these products, as follows.
The public Network Services MIB (as described in RFC 1565) contains generic variables designed to apply to all types of network service applications. Oracle has implemented those variables of this MIB that are relevant to three of the Oracle services:
Specific values for these variables are retrieved from a variety of sources, including configuration files, tables internal to the network service application, and from the master agent itself.
The Listener does not make use of any Network Services MIB variables.
The public RDBMS MIB is the proposed standard MIB for relational databases that has been defined by the IETF Working Group. This MIB allows for database discovery, identification of the database, and characterization of database size and activity level.
The public RDBMS MIB includes management variables that are both:
While this MIB makes a clear distinction between the database and its server, at this time the Oracle database subagent only recognizes the standard Oracle configuration of one database to one server. Thus, it does not account for the Oracle Parallel server or gateways.
The information in this MIB is mostly retrieved from dynamic performance tables (V$ tables) and the INIT.ORA configuration file of the Oracle7 and Oracle8 Servers.
The private Oracle Database MIB contains additional RDBMS statistics that are specific to the Oracle7 architecture. Like the public RDBMS MIB, the private Oracle Database MIB derives most of its information from dynamic performance tables of the database and from the INIT.ORA database configuration file.
The private Oracle Database MIB is platform-independent. Thus, one Oracle7 or Oracle8 Server MIB applies, whether supported on MVS or Windows or SCO. This allows a DBA to use one MIB, regardless of the number of platforms being managed.
In addition to the private database MIB, Oracle has defined private MIBs for the following products:
This section briefly covers how SNMP object identifiers (OIDs) are assigned, as it pertains to the MIBs that Oracle has implemented. Specifically, this section covers the following topics:
For more information on SNMP OIDs, see any of the standard SNMP texts listed in the preface.
For easy reference, tables listing the object identifiers for each object of a given Oracle-implemented MIB can be found in the appendix covering that MIB.
The SNMP standard (RFC 1442) specifies that an object identifier (OID) be used to uniquely identify each object. An OID is a sequence of elements that indicates a hierarchical organization of identifiers. These elements take the form of a series of "dotted" integers, similar in format to an Internet address.
An example OID for an private Oracle MIB variable follows:
In this OID:
Each of the elements listed above are assigned by entities outside Oracle. Thus, all objects within the Oracle ID space (that is, those objects to which Oracle has assigned OIDs), share the root OID 22.214.171.124.4.1.111.
Continuing use of the above example OID for illustration, Oracle has defined the elements of its private ID space as follows:
In addition to the four private Oracle MIBs that fall within Oracle OID space, Oracle is implementing portions of two public MIBs (Network Services MIB and RDBMS MIB) that fall outside Oracle OID space. The object IDs for the variables in these MIBs have been assigned in their respective RFCs.
An example OID for a public RDBMS MIB variable follows:
In this OID, the first four elements (126.96.36.199) match those for the Oracle root ID, indicating that this object falls under the iso, org, dod and internet objects. The fifth element (2), however, indicates that this object falls within the Internet management OID space. The seventh element (39) indicates that this object falls within the public RDBMS MIB. All variables of the public RDBMS MIB share this root OID of 188.8.131.52.2.1.39 The ninth element (2) indicates that this object is part of the rdbmsDbInfoTable. The eleventh element (3) identifies this as the leaf object rdbmsDbInfoSizeUnits.
An example OID for a public Network Services MIB variable follows:
In this OID, the first four elements (184.108.40.206) match those for the Oracle root ID, indicating that this object falls under the iso, org, dod and internet entities. The fifth element (2), however, indicates that this object falls within Internet management OID space. The seventh element (27), indicates that this object falls within the public Network Services MIB. All variables of the public Network Services MIB share this root OID of 220.127.116.11.2.1.27. The ninth element (1) indicates that this object is part of the applTable. The tenth element (6) identifies this as the leaf object applOperStatus.
Because variables in Oracle's MIBs are defined in tables, there can be multiple instances of a single variable. If, for example, there are two Oracle databases running on a given managed node, each database will have its own value for MIB variables such as applInboundAssociations, rdbmsDbName, and rdbmsSrvInfoDiskReads.
Not all variables are indexed on a per-service basis, as described above. It is also possible for a variable to have many instances for a single database. For example, while rdbmsSrvParamEntry describes a single database configuration parameter, that same managed node will have many instances of rdbmsSrvParamName.
To uniquely identify the multiple instances of these variables, each MIB table is indexed by one or more variables which, together, uniquely identify the rows of the table. (These index variables are conceptually equivalent to the primary key of a relational database table.) To refer to a particular instance of a variable, concatenate the variable's OID with the values of the index variables of the MIB table to which the variable belongs.
For instance, rdbmsDbName is defined within the rdbmsDbTable, which is indexed by the variable rdbmsDbIndex. For example, assume two databases are running on a host, one with SNMP index 2, the other with SNMP index 4. Then the name of the first database can be specified by concatenating the OID for rdbmsDbName (18.104.22.168.22.214.171.124.1.1.4) with the appropriate value of rdbmsDbIndex (2), or 126.96.36.199.188.8.131.52.184.108.40.206. Similarly, the name of the second database is the value of 220.127.116.11.18.104.22.168.22.214.171.124.
If a table is indexed by more than one variable, add the appropriate value of each index variable to the end of the OID, in the order they are listed in the table's MIB definition INDEX clause, separated by dots. The size (oraXDbDataFileSizeAllocated, or 126.96.36.199.188.8.131.52184.108.40.206.3) of the fifth data file (5) of the second database on the above host (whose rdbmsDbIndex is 4) is the value of 220.127.116.11.18.104.22.16822.214.171.124.3.4.5.