[这个贴子最后由yikaikai在 2002/12/10 10:00am 编辑]
Environment:
Oracle Intelligent Agent 9.0.1 (9i)
Frequently Asked Questions:
OVERVIEW:
1. What functions do the Intelligent Agent perform?
2. How does the Intelligent Agent do all that?
3. What are the major changes in the Agent with version 9i?
4. How do I start and stop my 9i Intelligent Agent?
5. What are the *.q files that I see in my Agent Directory?
CERTIFICATION:
6. Is the Agent supported on a system running DHCP?
7. Does the Agent require DNS resolution?
8. Does the Intelligent Agent work on Clustered Configurations?
INSTALLATION / CONFIGURATION:
9. Which CD-ROM contains the Intelligent Agent?
10. Can I run multiple Agents on a single server?
11. What is the name of the Intelligent Agent executable and where is it located?
12. Can the Intelligent Agent function on a node that does not have an Oracle database installed?
13. Which database releases are compatible with the 9i Agent?
14. Can I use the Intelligent Agent Release 9i to gather data on a remote host?
15. Where does the Intelligent Agent put its necessary support files?
16. How is the Intelligent Agent configured?
17. Which Intelligent Agent releases support Oracle EnterPRise Manager Release 9i?
18. Which version of the Oracle Intelligent Agent should I use? Can I download required patches?
19. Can I upgrade the Intelligent Agent without upgrading the database?
How do I do that?
20. Is it possible to upgrade to Intelligent Agent Release 9i without having to re-submit existing jobs or events?
21. What version of TCL does the Intelligent Agent Release 9i use?
22. Does Intelligent Agent 9i work on a machine with multiple network interface cards(NICs)?
23. What permissions should be assigned to the dbsnmp executable and who should start the Agent?
24. How do I change the dbsnmp passWord and is this password secure?
25. I need to change the hostname on my system. How can I make sure my Agent gets updated?
26. In the past, I couldn’t discover multiple Listener.ora files. Is this still a problem?
27. Can I change the TCP port numbers used by the Agent and Data Collection Cartridge?
TROUBLESHOOTING:
28. If my Agent doesn’t discover all the services running on my server, where do I start the troubleshooting the problem?
29. What is "Clean Starting" the Agent and how do I perform this Operation?
30. How to do I activate logging and tracing for my 9I Agent and Data Collection Cartridge?
31. In my dbsnmp.log file, I am finding an NMS-0001 error that says I can't connect to the SNMP Master Agent. Should I worry?
32. Does the DBSNMP database user pose a security problem?
33. What should I do if I see an error like "VNI 4009: Unable to contact the Agent" within the Enterprise Manager console?
34. Can I use the Remote Diagnostics Agent (RDA) to collect information for my Intelligent Agent’s configuration?
Questions with Answers
OVERVIEW:
1. What functions does the Intelligent Agent perform?
The Intelligent Agent provides the following core services:
Event management capabilities for the host machine, databases, listeners, concurrent managers, forms servers, Oracle HTTP listeners, etc.
Job execution and scheduling capabilities on the host machine, databases, listeners, concurrent managers, forms servers, Oracle HTTP listeners, etc.
Statistical data collection for the Performance Manager and Capacity Planner
Sending SNMP traps for events related to the database, listener or host
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2. How does the Intelligent Agent do all that?
The Intelligent Agent makes extensive use of an extended version of the TCL programming language. All job and event scripts are written in TCL and have the ability to do anything TCL can do. See the TCL document for details. Data collection is performed by making calls to the operating system or by accessing data in a monitored database.
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3. What are the major changes in the Agent with version 9i?
The major changes and new features in the 9i Agent are:
Data Gatherer (ODG) functionality has been fully integrated into the Intelligent Agent. Thus, the ODG is no longer a separate process.
A new control utility called "agentctl" has been introdUCed to start, stop, or check the status of the Agent.
Upon startup, a single dbsnmp process is created on UNIX platforms.
Administrators can suspend jobs, events and data collections on a target by using the Agent's agentctl utility.
Intelligent Agent Release 9i is also redesigned to handle a large number of events at the same time.
A new watchdog script runs in the background that restarts the Agent if it goes down. If the watchdog attempts to restart the Agent, information is written to the dbsnmp.nohup file (UNIX) and the Oracle<home>Agent.nohup file (Windows NT/2000).
For details on the 9i Intelligent Agent, please refer to the Oracle Intelligent Agent User's Guide Release 9i which is available as part of the Oracle Enterprise Manager documentation set.
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4. How do I start and stop my 9i Intelligent Agent?
For the 9i Agent on UNIX, a new Agent control utility called "agentctl" is used. The relevant agentctl commands are:
agentctl start agent
agentctl stop agent
agentctl status agent
agentctl restart agent (to stop and start the Agent using a single command)
On Windows NT, you can start and stop the Intelligent Agent service from the start menu: Start = Settings = Control Panel = NT Control Panel = Services screen.
On Windows 2000, you can start and stop the Agent Services: Go to Start menu = Settings = Control Panel = Administrative Tools = Services. Select the OracleAgent service. Right mouse click and select (start,stop, etc.). To modify the Startup Type, right mouse click and select Properties and edit the Startup Type as needed.
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5. What are the *.q files that I see in my Agent directory?
The ‘q’ files are state files maintained by the Agent. The files contain vital information about the jobs and events registered with the Agent, as well as authorized users and OMSs that have communicated with the Agent. The ‘q’ files are encrypted and the hostname of the system is used as part of the encryption key. The Agent reads these files each time the dbsnmp process is started. If the files are missing, the Agent will create new ones during startup. The files are also updated each time a job / event is processed or a new request is received.
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CERTIFICATION
6. Is the Agent supported on a system running DHCP?
Oracle does not recommend using DHCP as a method for oBTaining and IP Address for systems running the Intelligent Agent. Depending on the how your DCHP is configured, you may be receiving a new IP Address each time the system is rebooted. The Intelligent Agent needs a static IP Address in order to maintain communication with the Management Server. You can setup DHCP such that the IP Address never eXPires for that system, but you will not be able to launch the EM Reports WebSite if it’s running on the same system.
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7. Does the Agent require DNS hostname resolution?
The Intelligent Agent does require DNS resolution for communication with the Management Server. The DNS resolution must also include an entry in the DNS reverse lookup tables (nslookup). This depth of resolution was introduced during the EM 2.x timeframe to ensure resolution between domains.
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8. Does the Intelligent Agent work in a Clustered Environment?
The Intelligent Agent should work on supported Oracle Server Cluster Configurations. Development usually posts white papers discussing these configurations on Oracle Technology Network (OTN).
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INSTALLATION / CONFIGURATION
9. Which CD-ROM contains the Intelligent Agent?
If the Intelligent Agent is available for your platform, it will be installable from the Oracle Server CD-ROM. It should also be included on the 9iAS and Oracle applications 11i CD-ROMs.
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10. Can I run multiple Agents on a single server?
Because of TCP Port issues, you can only run one Intelligent Agent on a server. The Intelligent Agent must use port 1748 and 1754. These ports are not configurable and must be available when the Agent is started. As a best practice, if you have multiple installations of Oracle on a system, Oracle recommends that you keep only one dbsnmp executable from the most current release (i.e. rename the other dbsnmp executables). This will ensure that the wrong Agent is not started on the system.
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11. What is the name of the Intelligent Agent executable and where is it located?
The name of the Intelligent Agent executable has not changed. It is still called dbsnmp and it is located in $ORACLE_HOME/bin on Unix and %ORACLE_HOME\BIN on Windows NT/2000.
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12. Can the Intelligent Agent function on a node that does not have an Oracle database installed?
Yes it can. It can perform host-level management or management of non-database services like: Concurrent Managers, HTTP Servers, Form Servers, etc.
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13. Which database releases are compatible with the 9i Agent?
An Intelligent Agent can monitor and manage a database whose version is the same or lower than the Intelligent Agent's version. For example, Intelligent Agent Release 9i supports database versions 9i, 8.1.7.x, 8.1.6.x, and 8.0.6.x.
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14. Can I use the Intelligent Agent Release 9i to gather data on a remote host?
Yes, but only database-specific data will be collected from the remote host. If host information is required for Performance Manager or Capacity Planner, you will need to install and run an Intelligent Agent on that host.
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15. Where does the Intelligent Agent put its necessary support files?
The Agent’s files are located under the $ORACLE_HOME/network/agent/ subdirectory. This directory contains state files, output files and other directories used by the Agent. You should NOT modify / remove any Agent files unless directed by Oracle Support.
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16. How is the Intelligent Agent configured?
Since Release 7.3.3, Intelligent Agent configuration is automatic. The Agent reads a series of files to determine the Oracle Services that exist on the system as well as the hostname information. You will need to confirm your network configuration is setup correctly for TCP/IP (This includes setting up the DNS server for forward and reverse hostname lookups) and verify the databases on the server are listed in the Listener.ora file. The 9i Intelligent Agent does not recognize the Oracle Net feature that allows automatic registration of databases with the listener.
Please consult the Oracle Intelligent Agent User's Guide for more details.
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17. Which Intelligent Agent releases support Oracle Enterprise Manager Release 9i?
Intelligent Agent releases 9i, 8.1.7, 8.1.6.x, 8.0.6.x are supported with Enterprise Manager Release 9i. However, release 9I of the Intelligent Agent is highly recommended since it supports the complete set of features available from the Enterprise Manager 9i Console.
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18. Which version of the Oracle Intelligent Agent should I use? Can I download required patches?
Assuming that you are running the latest version of Enterprise Manager, we recommend that you upgrade to the latest available Intelligent Agent whenever possible. Not only does this provide you with the latest improvements but also newly released functionality that may only be available with the most recent Intelligent Agent. The most recent patches for the Oracle Intelligent Agent are available from Oracle Support or Oracle MetaLink.
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19. Can I upgrade the Intelligent Agent without upgrading the database? How do I do that?
Yes. You can upgrade the Intelligent Agent on a machine that is running earlier versions of the database. In these circumstances you need to install the Intelligent Agent into a new 9i Oracle home. If you have Jobs and Events registered with the older version Agent, you will need to run the upgrade script ‘nmumigr8’.
Please consult the Oracle Intelligent Agent User's Guide for more details or see <Note.160427.1>
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20. Is it possible to upgrade to Intelligent Agent Release 9i without having to re-submit existing jobs or events?
Yes. If you are upgrading to Release 9i* from Agent Release 8.1.7 or 8.1.6 or 8.0.6, then you can use a command line tool called nmumigr8 to migrate jobs, events and data collections. The migration tool "nmumigr8" is located under the 9i Agent's ORACLE_HOME/bin directory.
* Agent Release 9i must be installed in a new ORACLE_HOME.
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21. Does the Intelligent Agent 9i work on a machine with multiple network interface cards(NICs)?
Yes. Beginning with version 8.1.7, the Agent has the option of configuring the networking interface environment. By default, the 9i Agent will bind to the primary NIC on the machine and listen on that NIC for incoming job/event/data collection requests. Alternatively, you can configure the Agent to a) bind to a user specified NIC or b) bind to all NICs on the machine.
Please consult the Oracle Intelligent Agent User's Guide for more details.
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22. What version of TCL does the Intelligent Agent Release 9i use?
The 9i Intelligent Agent uses TCL Release 8.2.3.
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23. What permissions should be assigned to the dbsnmp executable and who should start the Agent?
On UNIX systems, the Intelligent Agent needs to run with a ‘setuid of root’ privilege. This is not the same as having the root user start the Agent. The Agent should be started as the ‘Oracle’ or equivalent user – not ‘root’. With the setuid bit turned on, the Agent will run jobs and events as the OS User assigned in the Node section of the EM Preferred Credentials. A check of the Agent’s permissions, should return:
-rwsr—s-- root <group>
On NT, Oracle recommends starting the Agent Service with the NT System account. This is setup automatically for you when the Agent is installed. If you change the startup account to another account, you may experience difficulties running jobs or events.
On both Unix and NT, the OS User defined in the Node section of the EM Preferred Credentials should have read / write to the ORACLE_HOME directory.
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24. How do I change the dbsnmp password and is this password secure?
You can change the dbsnmp password by first changing the password in the database and then adding a new line to the Agent’s snmp_rw.ora file:
SNMP.CONNECT.<service_name>.PASSWORD=<password>
-where <service_name> is the name of the database as it appears in the EM Console and the Agent’s snmp_ro.ora file.
New in 9i, if the password is changed in the snmp_rw.ora file, the first time the agent is started the parameter listed above will change and the password will become encrypted. This ensures the password is secure for this account. As a side note, some platforms will not allow white spaces around the equal sign.
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25. I need to change the hostname on my system. How can I make sure my Agent gets updated?
If the hostname gets changed where the Agent is running, the Agent’s state files (‘q’ files) will no longer be valid because the hostname is used as part of their encryption key. Unfortunately, the process to update the Agent is manual. You will need to save the jobs and events that are registered against the services on that node to the EM Job/Event Library, then ‘clean start’ the Agent (see <Note. 71913.1>
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26. In the past, I couldn’t discover multiple Listener.ora files. Is this still a problem?
The 9i Intelligent Agent can now discover listeners defined in multiple listener.ora files. This eliminates the need to keep all your listeners defined in a single listener.ora file.
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27. Can I change the TCP port numbers used by the Agent and Data Collection Cartridge?
Yes. You can change the TCP port number used by the Data Gathering Collection Cartridge. This cartridge is built into the 9I Intelligent Agent. The default ports are 1808 and 1809. You can now change these ports if needed.
Please consult the Oracle Intelligent Agent User's Guide for more details.
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TROUBLESHOOTING
28. If my Agent doesn’t discover all the services running on my server, where do I start the troubleshooting the problem?
If the Agent doesn’t discover all the services on your system, you will need to check the configuration files used by the Agent. The 9i Agent writes discovery errors in the nmiconf.log file.
Please consult <Note.166666.1> for more details on troubleshooting the discovery process.
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29. What is 'Clean Starting' the Agent and how do I perform this operation?
Under specific conditions, Oracle Support may recommend ‘clean starting’ the Agent. This is the process of cleaning up the Agent’s state files (‘q’ files). It is usually required when the Agent and the OMS because out of sync with each other or when the hostname of the system has changed.
Please consult <Note.71913.1> for more details on how the clean start the Agent process.
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30. How to do I activate logging and tracing for my 9I Agent and Data Collection Cartridge?
The tracing and logging parameters have changed for the 9i Intelligent Agent.
Please consult the Oracle Intelligent Agent User Guide or <Note.177236.1> for specific details.
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31. In my dbsnmp.log file, I am finding an NMS-0001 error that says I can't connect to the SNMP Master Agent. Should I worry?
No, this is a normal error unless you have a supported master SNMP agent running on your machine. What this error means is that the Intelligent Agent will not be able to respond to standard SNMP queries performed by a management station such as HP Openview. However, all Oracle Enterprise Manager functionality will still be available.
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32. Does the DBSNMP database user pose a security problem?
No. The DBSNMP user and password used by the Intelligent Agent to connect to the database are configurable.
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33. What should I do if I see an error like "VNI 4009: Unable to contact the Agent" within the Enterprise Manager console?
This is a very common error and could be as simple as the Agent is not started or as complicated as network resolution problems. Please refer to <<Note.166666.1 for a troubleshooting path on how to resolve this issue.
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34. Can I use the Remote Diagnostics Agent (RDA) to collect information for my Intelligent Agent’s configuration?
Currently, the RDA does not provide any detailed information on the actual Intelligent Agent process or configuration. However, it does gather information on the Network Configuration and the OS that might be helpful for Oracle Support when dealing with Intelligent Agent issues. There are plans to enhance the RDA to collect Intelligent Agent specific information in a later version.
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