Tnsnames oracle где лежит
I have an Oracle tnsnames.ora file from my previous workplace. I want to pick it up with my newly installed PL SQL Developer on another computer. I have copied the file into ..ORACLE/product/11.2.0/client_32/NETWORK/ADMIN but PL SQL Developer cannot find it.
When it starts it is not showing me any choice of database. In About->i->TNSNames I dont see any lines
I have found a number of advices to look for it in Tools->Preferences->Database->. but I dont have a Database tab in my preferences.
How can I fix it?
Once I had the same problem. I found, that my PLSQL Developer had one more file tnsnames.ora in a program folder (the same folder, where file plsqldev.exe is situated). Make sure that it is not your case.
Local Naming Parameters
This section lists and describes the tnsnames.ora file parameters that comprise connect descriptors. Configuration parameters fall into the following categories:
General Syntax of tnsnames.ora
The basic syntax for a tnsnames.ora file is shown in Example 6-1.
Example 6-1 Basic Format of tnsnames.ora File
In the preceding example, DESCRIPTION contains the connect descriptor, ADDRESS contains the protocol address, and CONNECT_DATA contains the database service identification information.
ADDRESS
To define a single listener protocol address. Put this parameter under either the ADDRESS_LIST parameter or the DESCRIPTION parameter.
Chapter 4, "Protocol Address Configuration" for descriptions of the correct parameters to use for each protocol
Multiple Address Lists in tnsnames.ora
The tnsnames.ora file also supports connect descriptors with multiple lists of addresses, each with its own characteristics. In Example 6-3, two address lists are presented. The first address list features client load balancing and no connect-time failover , affecting only those protocol addresses within the ADDRESS_LIST . The second protocol address list features connect-time failover and no client load loading balancing, affecting only those protocol addresses within the ADDRESS_LIST . The client first tries the first or second protocol address at random, then tries protocol addresses three and four sequentially.
Example 6-3 Multiple Address Lists in tnsnames.ora
Oracle Net Manager supports only the creation of one protocol address list for a connect descriptor.
SOURCE_ROUTE
To enable routing through multiple protocol addresses.
When you set to on or yes , Oracle Net uses each address in order until the destination is reached.
To use Oracle Connection Manager, an initial connection from the client to Oracle Connection Manager is required, and a second connection from Oracle Connection Manager to the listener is required.
Put this parameter under either the DESCRIPTION_LIST parameter, the DESCRIPTION parameter, or the ADDRESS_LIST parameter.
Сетевая служба TNS Listener – достаточно мощный инструмент, почти полностью контролирующий доступ к СУБД и предоставляющий возможность доступа к командам ОС. Листенер состоит из двух исполняемых и нескольких конфигурационных файлов.
Исполняемые файлы tnslsnr и lsnrctl расположены в директории $ORACLE_HOME/bin (переменная $ORACLE_HOME отображает путь к директории, в которую установлена СУБД). Конфигурационные файлы расположены в директории $ORACLE_HOME/network/admin. Рассмотрим подробнее назначение этих файлов.
LOAD_BALANCE
To enable or disable client load balancing for multiple protocol addresses.
When you set the parameter to on , yes , or true , Oracle Net progresses the list of addresses in a random sequence, balancing the load on the various listener or Oracle Connection Manager protocol addresses. When you set the parameter to off , no , or false , Oracle Net tries the first address in the address list. If the connection fails and the failover parameter is enabled, then Oracle Net tries the addresses sequentially until one succeeds.
Put this parameter under either the DESCRIPTION_LIST parameter, the DESCRIPTION parameter, or the ADDRESS_LIST parameter.
on for DESCRIPTION_LIST
Режимы работы Листенера
В зависимости от конфигурации, описанной в listener.ora, служба Листенера может работать в трех различных режимах:
- Database – предоставляет удаленный доступ к конкретной базе. Этот режим является стандартным и потому более всего распространен.
- PLSExtProc – предоставляет доступ к командам операционной системы через процедуры PL/SQL.
- Executable – предоставляет удаленный доступ к командам операционной системы. Он позволяет продуктам Oracle, таким как, например, Oracle EBusiness Suite и Oracle Database общаться между собой через Листенер.
На рисунке ниже показан Листенер, сконфигурированный в двух режимах: Database и PLSExtProc. За подключение к СУБД отвечает сервис с именем «orcl9» (режим Database), за выполнение внешних процедур отвечает сервис PLSExtProс.
Мы же в следующей статье блога перейдем к очень интересному вопросу – атакам на службу Листенера. Применим пошаговую стратегию, начав со стандартных атак на незащищенную службу и постепенно переходя ко все более сложным вариантам атак, на защищенную службу Листенера. Большинство примеров будет работать как старой версии СУБД Oracle 8i, которая, тем не менее, до сих пор (. ) встречается в корпоративных сетях, так и на самый распространенный на данный момент версии 11g.
ENABLE
The keepalive feature on the supported TCP transports can be enabled for a net service client by putting (ENABLE=broken) under the DESCRIPTION parameter in the connect string. The keepalive feature allows the caller to detect a terminated remote server, although typically it takes 2 hours or more to notice. On the client side, the default for tcp_keepalive is off . Operating system TCP configurables, which vary by platform, define the actual keepalive timing details.
Protocol Address Section
The protocol address section of the tnsnames.ora file specifies the protocol addresses of the listener.
ADDRESS
Use the parameter ADDRESS to define a single listener protocol address.
Embed this parameter under either the ADDRESS_LIST parameter or the DESCRIPTION parameter.
ADDRESS_LIST
Use the parameter ADDRESS_LIST to define a list of protocol addresses. If there is only address list, ADDRESS_LIST is not necessary.
Embed this parameter under either the DESCRIPTION parameter or the DESCRIPTION_LIST parameter.
Sqlnet.ora
Этот конфигурационный файл отвечает за сетевые настройки Листенера. В нем нас прежде всего интересуют опции, связанные с безопасностью, - это на стройки шифрования передачи данных, аутентификации и разграничения прав доступа к Листенеру по IP-адресам (Valid Node Checking).
RECV_BUF_SIZE
To specify, in bytes, the buffer space for receive operations of sessions. This parameter is supported by the TCP/IP, TCP/IP with SSL, and SDP protocols.
Put this parameter under the DESCRIPTION parameter or at the end of the protocol address.
Additional protocols might support this parameter on certain operating systems. Refer to the operating system-specific documentation for additional information about additional protocols.
The default value for this parameter is specific to the operating system.
Setting this parameter in the connect descriptor for a client overrides the RECV_BUF_SIZE parameter at the client-side sqlnet.ora file.
Oracle Database Net Services Administrator's Guide for additional information about configuring this parameter
To instruct Oracle Net to optimize the transfer rate of data packets being sent across the network with a specified session data unit (SDU) size.
Put this parameter under the DESCRIPTION parameter.
8192 bytes (8 KB).
512 to 65535 bytes.
Setting this parameter in the connect descriptor for a client overrides the DEFAULT_SDU_SIZE parameter at client-side sqlnet.ora file.
Oracle Database Net Services Administrator's Guide for complete SDU usage and configuration information
Lsnrctl
Lsnrctl является консольной утилитой, используемой для администрирования Листенера. С ее помощью можно управлять Листенером как локально, так и удаленно. Команды управления включают в себя возможность настройки протоколирования событий, смены пароля или удаленного перезапуска Листенера.
Connect Descriptor Descriptions
Each connect descriptor is contained within a DESCRIPTION parameter. Multiple connect descriptors are characterized by the DESCRIPTION_LIST parameter. These parameters are described next.
DESCRIPTION
Use the DESCRIPTION parameter as a container for a connect descriptor.
Embed this parameter under the DESCRIPTION_LIST parameter.
DESCRIPTION_LIST
Use he DESCRIPTION_LIST parameter defines a list of connect descriptors for a particular net service name.
Tnslsnr
Сердце Листенера, отвечающее за весь основной функционал службы, – процесс tnslsnr, который выполняет роль прокси-сервера и перенаправляет запросы от клиента непосредственно к СУБД. Процесс tnslsnr по умолчанию запускается с привилегиями пользователя Oracle в ОС UNIX и с привилегиями пользователя
Local System в ОС Windows NT/2000/2003. Так как учетная запись «oracle», создаваемая при установке СУБД на UNIX-системах, не имеет административных привилегий, риск поставить под угрозу весь сервер при компрометации Листенера в UNIXсистемах по умолчанию ниже.
Connect Data Section
The connection data section of the tnsnames.or a file specifies the name of the destination service.
CONNECT_DATA
Use the parameter CONNECT_DATA to define the service to which to connect.
Embed this parameter under the DESCRIPTION parameter.
CONNECT_DATA permits the following subparameters:
FAILOVER_MODE
Use the parameter FAILOVER_MODE to instruct Oracle Net to fail over to a different listener if the first listener fails during runtime. Depending upon the configuration, session or any SELECT statements which were in progress are automatically failed over.
This type of failover is called Transparent Application Failover (TAF) and should not be confused with the connect-time failover FAILOVER parameter.
Embed this parameter under the CONNECT_DATA parameter.
FAILOVER_MODE supports the following subparameters:
BACKUP : Specify the failover node by its net service name. A separate net service name must be created for the failover node.
TYPE : Specify the type of failover. Three types of Oracle Net failover functionality are available by default to Oracle Call Interface (OCI) applications:
session : Fails over the session; that is, if a user's connection is lost, a new session is automatically created for the user on the backup. This type of failover does not attempt to recover selects.
select : Allows users with open cursors to continue fetching on them after failure. However, this mode involves overhead on the client side in normal select operations.
none : This is the default, in which no failover functionality is used. This can also be explicitly specified to prevent failover from happening.
METHOD : Specify how fast failover is to occur from the primary node to the backup node:
basic : Establishes connections at failover time. This option requires almost no work on the backup database server until failover time.
preconnect : Pre-establishes connections. This provides faster failover but requires that the backup instance be able to support all connections from every supported instance.
RETRIES : Specify the number of times to attempt to connect after a failover. If DELAY is specified, RETRIES defaults to five retry attempts.
DELAY : Specify the amount of time in seconds to wait between connect attempts. If RETRIES is specified, DELAY defaults to one second.
The installation process creates a tnsnames.ora file on each node.
The tnsnames.ora file acts as a repository of net service names. Each net service name is associated with a connect identifier. A connect identifier is an identifier that maps a user-defined name to a connect descriptor. A connect descriptor contains the following information:
The network route to the service, including the location of the listener through a protocol address
The SERVICE_NAME parameter, with the value set to the name of a database service
The SERVICE_NAME parameter you use in the tnsnames.ora file is singular, because you can specify only one service name. The SERVICE_NAME parameter is different from the service_names database initialization parameter. The service_names database parameter defaults to the global database name, a name comprising the db_name and db_domain parameters in the initialization parameter file. When you add service names using SRVCTL or Oracle Enterprise Manager Cloud Control, it lists additional cluster-managed services for the database.
The tnsnames.ora file is located in both the Grid_home \network\admin and Oracle_home \network\admin directories. By default, the tnsnames.ora file is read from the Grid home when Oracle Grid Infrastructure is installed.
With Oracle Clusterware 11 g Release 2 and later, the listener association no longer requires tnsnames.ora file entries. The listener associations are configured as follows:
Oracle Database Configuration Assistant (DBCA) no longer sets the LOCAL_LISTENER parameter. The Oracle Clusterware agent that starts the database sets the LOCAL_LISTENER parameter dynamically, and it sets it to the actual value, not an alias. So listener_ alias entries are no longer needed in the tnsnames.ora file.
The REMOTE_LISTENER parameter is configured by DBCA to reference the SCAN and SCAN port, without any need for a tnsnames.ora entry. Oracle Clusterware uses the Easy Connect naming method with scanname : scanport , so no listener associations for the REMOTE_LISTENER parameter are needed in the tnsnames.ora file.
Example 6-2 Adding a Second Listener to an Oracle RAC Database
If you created a database named orcl1 , to add a second listener, listening on port 2012, use a command similar to the following command to have the database register with both listeners on startup:
Oracle Database Net Services Administrator's Guide for more information about the tnsnames.ora file
This chapter provides a complete listing of the tnsnames.ora file configuration parameters.
This chapter contains the following topics:
Multiple Address Lists in tnsnames.ora
The tnsnames.ora file also supports connect descriptors with multiple lists of addresses, each with its own characteristics. In , two address lists are presented. The first address list features client load balancing and no connect-time failover , affecting only those protocol adresses within the ADDRESS_LIST . The second protocol address list features connect-time failover and no client load loading balancing, affecting only those protocol addresses within the ADDRESS_LIST . The client first tries either the first or second protocol address at random, then tries protocol addresses three and four sequentially.
Example 6-3 Multiple Address Lists in tnsnames.ora
DESCRIPTION_LIST
To define a list of connect descriptors for a particular net service name.
Overview of Local Naming Parameters
This tnsnames.ora file is a configuration file that contains net service name s mapped to connect descriptor s for the local naming method, or net service names mapped to listener protocol addresses.
A net service name is an alias mapped to a database network address contained in a connect descriptor. A connect descriptor contains the location of the listener through a protocol address and the service name of the database to which to connect. Clients and database servers (that are clients of other database servers) use the net service name when making a connection with an application.
By default, the tnsnames.ora file is located in the ORACLE_HOME/network/admin directory. Oracle Net will check the other directories for the configuration files. For example, the order checking the tnsnames.ora file is as follows:
The directory specified by the TNS_ADMIN environment variable. If the file is not found in the directory specified, then it is assumed that the file does not exist.
If the TNS_ADMIN environment variable is not set, then Oracle Net will check the ORACLE_HOME/network/admin directory.
On Microsoft Windows, the TNS_ADMIN environment variable is used if it is set in the environment of the process. If the TNS_ADMIN environment variable is not defined in the environment, or the process is a service which does not have an environment, then Microsoft Windows scans the registry for a TNS_ADMIN parameter.
Oracle operating system-specific documentation
Protocol Address Section
The protocol address section of the tnsnames.ora file specifies the protocol addresses of the listener. If there is only one listener protocol address, then use the ADDRESS parameter. If there is more than one address, then use the ADDRESS_LIST parameter.
Optional Parameters for Address Lists
For multiple addresses, the following parameters are available:
SEND_BUF_SIZE
To specify, in bytes, the buffer space for send operations of sessions. This parameter is supported by the TCP/IP, TCP/IP with SSL, and SDP protocols.
Additional protocols might support this parameter on certain operating systems. Refer to the operating system-specific documentation for additional information about additional protocols.
Put this parameter under the DESCRIPTION parameter or at the end of the protocol address.
The default value for this parameter is operating system-specific.
Setting this parameter in the connect descriptor for a client overrides the SEND_BUF_SIZE parameter at the client-side sqlnet.ora file.
Oracle Database Net Services Administrator's Guide for additional information about configuring this parameter
General Syntax of tnsnames.ora
The basic syntax for a tnsnames.ora file is shown in . DESCRIPTION contains the connect descriptor, ADDRESS contains the protocol address, and CONNECT_DATA contains the database service identification information.
Example 6-1 Basic Format of tnsnames.ora File
DESCRIPTION
To specify a container for a connect descriptor. Put this parameter under the DESCRIPTION_LIST parameter.
Multiple Descriptions in tnsnames.ora
A tnsnames.ora file can contain net service names with one or more connect descriptors. Each connect descriptor can contain one or more protocol addresses. Example 6-2 shows two connect descriptors with multiple addresses. DESCRIPTION_LIST defines a list of connect descriptors.
Example 6-2 Net Service Name with Multiple Connect Descriptors in tnsnames.ora
Oracle Net Manager does not support the creation of multiple connect descriptors for a net service name when using Oracle Connection Manager.
Connect-Time Failover and Client Load Balancing with Oracle Connection Managers
When a connect descriptor in a tnsnames.ora file contains at least two protocol addresses for Oracle Connection Manager , parameters for connect-time failover and load balancing can be included in the file.
Example 6-4 illustrates failover of multiple Oracle Connection Manager protocol addresses.
Example 6-4 Multiple Oracle Connection Manager Addresses in tnsnames.ora
In Example 6-4, the syntax does the following:
The client is instructed to connect to an protocol address of the first Oracle Connection Manager, as indicated by:
The first Oracle Connection Manager is instructed to connect to the first protocol address of another Oracle Connection Manager. If the first protocol address fails, then it tries the second protocol address. This sequence is specified with the following configuration:
The Oracle Connection Manager connects to the database service using the following protocol address:
Example 6-5 illustrates client load balancing among two Oracle Connection Managers and two protocol addresses:
Example 6-5 Client Load Balancing in tnsnames.ora
In Example 6-5, the syntax does the following:
The client is instructed to pick an ADDRESS_LIST at random and to failover to the other if the chosen ADDRESS_LIST fails. This is indicated by the LOAD_BALANCE and FAILOVER parameters being set to on .
When an ADDRESS_LIST is chosen, the client first connects to the Oracle Connection Manager, using the Oracle Connection Manager protocol address that uses port 1630 indicated for the ADDRESS_LIST .
The Oracle Connection Manager then connects to the database service, using the protocol address indicated for the ADDRESS_LIST .
Connect-Time Failover and Client Load Balancing with Oracle Connection Managers
When a connect descriptor in a tnsnames.ora file contains at least two protocol addresses for Oracle Connection Manager , parameters for connect-time failover and load balancing can be included in the file.
illustrates failover of multiple Oracle Connection Manager protocol addresses.
Example 6-4 Multiple Oracle Connection Manager Addresses in tnsnames.ora
The client is instructed to connect to an protocol address of the first Oracle Connection Manager, as indicated by:
The first Oracle Connection Manager is then instructed to connect to the first protocol address of another Oracle Connection Manager. If the first protocol address fails, then it tries the second protocol address. This sequence is specified with the following configuration:
The Oracle Connection Manager then connects to the database service using the following protocol address:
illustrates client load balancing among two Oracle Connection Managers and two protocol addresses:
Example 6-5 Client Load Balancing in tnsnames.ora
The client is instructed to pick an ADDRESS_LIST at random and to failover to the other if the chosen ADDRESS_LIST fails. This is indicated by the LOAD_BALANCE and FAILOVER parameters being set to on .
When an ADDRESS_LIST is chosen, the client first connects to the Oracle Connection Manager, using the Oracle Connection Manager protocol address that uses port 1630 indicated for the ADDRESS_LIST .
The Oracle Connection Manager then connects to the database service, using the protocol address indicated for the ADDRESS_LIST .
Connect Descriptor Descriptions
Each connect descriptor is contained within the DESCRIPTION parameter. Multiple connect descriptors are characterized by the DESCRIPTION_LIST parameter. These parameters are described in this section.
Overview of Local Naming Parameters
This tnsnames.ora file is a configuration file that contains net service name s mapped to connect descriptor s for the local naming method, or net service names mapped to listener protocol address es.
A net service name is an alias mapped to a database network address contained in a connect descriptor. A connect descriptor contains the location of the listener through a protocol address and the service name of the database to which to connect. Clients and database servers (that are clients of other database servers) use the net service name when making a connection with an application.
By default, tnsnames.ora is located in the $ORACLE_HOME/network/admin directory on UNIX operating systems and in the ORACLE_HOME \network\admin directory on Windows operating systems. tnsnames.ora can also be stored the following locations:
The directory specified by the TNS_ADMIN environment variable or registry value
On UNIX operating systems, the global configuration directory. For example, on the Solaris Operating System, this directory is /var/opt/oracle .
FAILOVER
To enable or disable connect-time failover for multiple protocol addresses.
When you set the parameter to on , yes , or true , Oracle Net, at connect time, fails over to a different address if the first protocol address fails. When you set the parameter to off , no , or false , Oracle Net tries one protocol address.
Put this parameter under the DESCRIPTION_LIST parameter, the DESCRIPTION parameter, or the ADDRESS_LIST parameter.
Do not set the GLOBAL_DBNAME parameter in the SID_LIST_ listener_name section of the listener.ora . A statically configured global database name disables connect-time failover.
on for DESCRIPTION_LIST , DESCRIPTION , and ADDRESS_LIST .
6 Answers 6
If you are certain your tnsnames.ora file is correct (e.g. by testing the connection with the Oracle Net Config Assistant, or logging in successfully with SQLplus), and you are able to open the PLSQL Developer application, but you still can't connect to the database in PLSQL Developer, then follow these steps:
In PLSQL Developer (version 11.0) go to Help/Support Info
Click the TNS Names tab. If the path in PLSQL Developer is wrong it will be blank (no tns file found) or incorrect (wrong tns file in use)
On the Info tab scroll down to the TNS File entry and to see the path for the tns file PLSQL Developer is using. Very likely this is wrong.
To correct the path:
open a command prompt
navigate to the PLSQL Developer directory in Program Files
enter this command:
*path is to the directory containing your tnsnames.ora file - for me this is: c:\Oracle\product\11.2.0\client_1\network\admin
A new PLSQL Developer UI will open and you should be able to connect.
Make sure you have a Windows environment variable TNS_ADMIN set to the same path
- On Windows 7 you go to Start, Control Panel, System, Advanced System Settings, Environment Variables to view/add/update environment variables
Answer is correct, just noting additionally, TNS_ADMIN argument should be to the path only, do not enter tnsnames.ora into the argument, it is assumed
Which Oracle client are you using?
Oracle 64bit 11g client isn't support in PLSQL Developer. Try to install 32bits client.
It's not that the client isn't supported but if you run a 32 bit Oracle 11g client you need to run a 32 bit PLSQL installation. If you run a 64 bit Oracle 11g client you need to run a 64 bit PLSQL installation
I had the same problema, but as described in the manual.pdf, you have to:
- PATH: Needs to include the Instant Client directory where oci.dll is located
- TNS_ADMIN: Needs to point to the directory where tnsnames.ora is located.
- NLS_LANG: Defines the language, territory, and character set for the client.
Check if tnsnames.ora not saved as text file with an additional hidden .txt extension. Windows File Explorer will not show it by deafult settings.
I recently had the problem of deleting the tnsnames.ora from the path where I had it, my solution was to create an environment variable called TNS_NAME with the value the path where the tnsnames.ora file is located and ready
You most certainly have a databases tab in sql developer (all versions I've used in the past have this). Maybe check again? Perhaps, you're looking in the wrong location.
On a mac, the preferences is under "Oracle SQL Developer" (top left) -> Preferences -> Database -> Advanced -> section called Tnsnames Directory is where you specify the file.
On windows (going from memory so might have to search if this isn't correct) Tools -> Preferences -> Database -> Advanced -> section called Tnsnames Directory is where you specify the file.
See this image
This chapter provides a complete listing of the tnsnames.ora file configuration parameters.
This chapter contains these topics:
Multiple Descriptions in tnsnames.ora
A tnsnames.ora file can contain net service names with one or more connect descriptors. Each connect descriptor can contain one or more protocol addresses. Example 6-2 shows two connect descriptors with multiple addresses. DESCRIPTION_LIST defines a list of connect descriptors.
Example 6-2 Net Service Name with Multiple Connect Descriptors in tnsnames.ora
ADDRESS_LIST
To define a list of protocol addresses. If there is only one listener protocol address, then ADDRESS_LIST is not necessary. Put this parameter under either the DESCRIPTION parameter or the DESCRIPTION_LIST parameter.
Optional Parameters for Lists
For multiple addresses, the following parameters are available for usage:
FAILOVER
Use the parameter FAILOVER to enable or disable connect-time failover for multiple protocol addresses.
When you set the parameter to on , yes , or true , Oracle Net, at connect time, fails over to a different address if the first protocol address fails. When you set the parameter to off , no , or false , Oracle Net tries one protocol address.
Embed this parameter under either the DESCRIPTION_LIST parameter, the DESCRIPTION parameter, or the ADDRESS_LIST parameter.
on for DESCRIPTION_LIST s, DESCRIPTION s, and ADDRESS_LIST s
LOAD_BALANCE
Use the parameter LOAD_BALANCE to enable or disable client load balancing for multiple protocol addresses.
When you set the parameter to on , yes , or true , Oracle Net progresses through the list of addresses in a random sequence, balancing the load on the various listener or Oracle Connection Manager protocol addresses. When you set the parameter to off , no , or false , Oracle Net tries the protocol addresses sequentially until one succeeds.
Embed this parameter under either the DESCRIPTION_LIST parameter, the DESCRIPTION parameter, or the ADDRESS_LIST parameter.
on for DESCRIPTION_LIST s
RECV_BUF_SIZE
Use the parameter RECV_BUF_SIZE to specify, in bytes, the buffer space for receive operations of sessions. This parameter is supported by the TCP/IP, TCP/IP with SSL, and SDP protocols.
The default value for this parameter is operating-system specific. The default for the Solaris 2.6 Operating System is 32768 bytes.
Setting this parameter in the connect descriptor for a client overrides the RECV_BUF_SIZE parameter at the clientside sqlnet.ora file.
Use the parameter SDU to instruct Oracle Net to optimize the transfer rate of data packets being sent across the network with the session data unit (SDU) size you specify.
Embed this parameter under the DESCRIPTION parameter.
512 bytes to 32768 (32 KB)
Setting this parameter in the connect descriptor for a client overrides the DEFAULT_SDU_SIZE parameter at clientside sqlnet.ora file.
SEND_BUF_SIZE
Use the parameter SEND_BUF_SIZE to specify, in bytes, the buffer space for send operations of sessions. This parameter is supported by the TCP/IP, TCP/IP with SSL, and SDP protocols.
The default value for this parameter is operating-system specific. The default for the Solaris 2.6 Operating System is 8192 bytes.
Setting this parameter in the connect descriptor for a client overrides the SEND_BUF_SIZE parameter at the clientside sqlnet.ora file.
SOURCE_ROUTE
Use the parameter SOURCE_ROUTE to enable routing through multiple protocol addresses.
When you set to on or yes , Oracle Net uses each address in order until the destination is reached.
To use Oracle Connection Manager, an initial connection from the client to Oracle Connection Manager is required, and a second connection from Oracle Connection Manager to the listener is required.
Embed this parameter under either the DESCRIPTION_LIST parameter, the DESCRIPTION parameter, or the ADDRESS_LIST parameter.
TYPE_OF_SERVICE
Use the parameter TYPE_OF_SERVICE parameter to specify the type of service to use for an Oracle Rdb database. This parameter should only be used if the application supports both an Oracle Rdb and Oracle database service, and you want the application to load balance between the two.
Embed this parameter under the DESCRIPTION parameter.
Tnsnames.ora
В этом файле хранится соответствие кратких имен (Net Service Names) длинным дескрипторам соединений для упрощения межсетевого взаимодействия. Нам это файл интересен тем, что в нем может находиться информация о SSL-сертификатах, используемых для аутентификации. В нем также могут храниться данные для подключения к другим серверам СУБД, в том числе и SID. Пример одной записи из файла Tnsnames.ora:
Здесь мы видим, что на хосте с IPадресом 192.168.40.14 на порту 1521 запущена служба Листенера. У базы данных, установленной на этом сервере, SID равно ORCL102.
Listener.ora
Этот конфигурационный файл отвечает за связь Листенера с СУБД. Для нас важнейшим моментом является хранимая в нем строка подключения, которая со держит такие параметры подключения, как системный идентификатор (SID) и порт, на который будут приниматься запросы для данного SID. Как будет ясно в дальнейшем, эта информация является во многом определяющей при проведении начального этапа проникновения в СУБД Oracle. Этот файл очень важен для нас – получив к нему доступ с возможностью внесения модификаций, мы сможем обойти такие ограничения безопасности, как пароль на службу Листенера и протоколирование событий. Пример конфигурационного файла:
Здесь мы видим, что на хосте с именем Ora, на порту 1521 запущен экземпляр базы данных. Кроме того, в этом файле могут храниться такие параметры, как пароль на доступ к Листенеру, директория хранения логфайлов и пр. Изменения в конфигурации Листенера могут быть сделаны напрямую путем правки файла listener.ora или с использованием командного интерфейса утилиты lsnrctl.
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