The role of Sqlnet.ora in monitoring

The two most commonly used features of

  Sqlnet.ora are:
Client action = = connection is used to specify the order in which the names of the client's name resolution queries are named. ==>> NAMES. Directory_path= (TNSNames, Onames, hostname)
The service side works with the client at the same time = authentication Mode ==>> sqlnet. Authentication_services

Sqlnet.ora content details see official documentation: HTTP://DOCS.ORACLE.COM/CD/B19306_01/NETWORK.102/B14213/ sqlnet.htm#netrf006
Configure Sqlnet.ora to restrict IP access oracle http://blog.csdn.net/leshami/article/details/6629141
Some important parameters and explanations:
1.bequeath_detach
Controls signal handling switches in UNIX systems, by default No, that is, signal handling is open.
2.default_sdu_size
Specifies the size of the session data Unit (SDU), which is bytes, and it is recommended that you set this parameter on both the client side and the server side to ensure that the same SDU size is used when linking. If the client-side and server-side configured values do not match, the smaller ones are used.
3.log_directory_client/log_directory_server
Specifies the location of the client-side/server log file
4.NAMES. Default_domain
Sets the domain for client resolution names
5.NAMES. Directory_path
Specifies the order of the client name resolution method, by default names.directory_path= (TNSNames, Onames, hostname)
value can be tnsnames, LDAP (dictionary server), Hostname/ezconnect,cds (Distributed Environment), NIS (Network Information Service (NIS)
6.sqlnet_allowed_ Logon_versioNS
Specifies the version sqlnet_allowed_logon_versions= (10,9,8)
7.SQLNET of Oracle running the link. Authentication_services
Specifies to start one or more authentication services
Authentication Methods Available with Oracle Net services:
None for No Uthentication methods. A valid username and password can is used to access the database.
All to all authentication methods
nts for Windows NT native authentication
8.SQLNET. Inbound_connect_timeout
Specifies the time when the client does not have a successful link timeout. Oracle interrupts the link and complains when the timeout expires.
9.ssl_version
Specifies the version of the SSL link,
10.TCP. Excluded_nodes
Specifies that nodes that are not allowed access to Oracle can use the hostname or IP address
11.TCP. Invited_nodes
Specifies that clients that are allowed access to DB have a higher priority than tcp.excluded_nodes.
12.TCP. Validnode_checking
uses this parameter to enable the two parameters above.
13.TNSPING. Trace_directory
Use this parameter to specify the directory of the tnsping trace file, by default, $oracle_home/network/trace directory
More parameter information see: ORACLE Database Net Services Reference

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The sequential way of parsing a query when connected experiment: ==>> NAMES. Directory_path= (TNSNames, Onames, hostname)

Instructions on the official document: use the parameter NAMES. Directory_path to specify the "naming methods used for client name resolution lookups.
NAMES. directory_path==>> specifies the order in which name resolution queries are used for client-side naming methods. No connection mode in this parameter will be available.
[Oracle@ocm1 admin]$ Cat Tnsnames.ora
BYS3 =
(DESCRIPTION =
(address = (PROTOCOL = TCP) (HOST = 192.168.1.211) (PORT =1521)
(Connect_data =
(SERVER = dedicated)
(service_name = BYS3)
)
)

1. Configuration Sqlnet.ora contains: names.directory_path= (tnsnames), can only use the local name in TNSNames, easy connection will error

Example:
[Oracle@ocm1 admin]$ VI Sqlnet.ora
NAMES. Directory_path= (TNSNames)
~
[ORACLE@OCM1 admin]$ sqlplus BYS/BYS@BYS3--use local name to connect
Sql*plus:release 10.2.0.1.0-production on Fri 17 11:13:16 2014
Copyright (c) 1982, +, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition release 11.2.0.4.0-production
With the partitioning, OLAP, Data Mining and real application testing options
Sql> exit

[ORACLE@OCM1 admin]$ sqlplus BYS/BYS@192.168.1.211:1521/BYS3--Use simple connection method, cannot connect
Sql*plus:release 10.2.0.1.0-production on Fri 17 11:13:27 2014
Copyright (c) 1982, +, Oracle. All rights reserved.
ERROR:
Ora-12154:tns:could not resolve the connect identifier specified

2. Configuration Sqlnet.ora contains: names.directory_path= (Tnsnames,ezconnect), at this time use TNSNames in this place name and simple connection can be

[oracle@ocm1 admin]$ cat Sqlnet.ora
NAMES. Directory_path= (tnsnames,ezconnect)
Use this place name and easy connection in TNSNames
[oracle@ocm1 admin]$ sqlplus bys/bys@bys3
SQL *plus:release 10.2.0.1.0-production on Fri 11:18:47 2014
Copyright (c) 1982,%, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition release 11.2.0.4.0-production
with the partitioning, O LAP, Data Mining and real application testing options
Sql>

[Oracle@ocm1 admin]$, Sqlplus bys/bys@192.168.1. 211:1521/BYS3
Sql*plus:release 10.2.0.1.0-production on Fri before 11:13:59 2014
Copyright (c) 1982,%, Orac Le. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition release 11.2.0.4.0-production
with the partitioning, O LAP, Data Mining and real application testing options
Sql> exit
############################################# ####

Service side and client at the same time = = Authentication Way ==>> sqlnet. Authentication_services

There are three parameters:
None for no authentication methods. A valid username and password can is used to access the database.
All to all authentication methods
NTS for Windows NT native authentication---this is only useful for Windows.

When client and server sqlnet.authentication_services= (all) cannot log in with aa/bb username password. One side is none to connect.

1. Server-side does not configure Sqlnet.ora files, the client configuration sqlnet.authentication_services= (all), you can log on normally.

[Oracle@ocm1 admin]$ Cat Sqlnet.ora
NAMES. Directory_path= (Tnsnames,ezconnect)
Sqlnet. Authentication_services= (All)
[Oracle@ocm1 admin]$ Sqlplus Bys/bys@bys3
Sql*plus:release 10.2.0.1.0-production on Fri 17 11:24:45 2014
Copyright (c) 1982, +, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition release 11.2.0.4.0-production
With the partitioning, OLAP, Data Mining and real application testing options

Sql>

2. When client and server are configured simultaneously: sqlnet.authentication_services= (All) cannot login with aa/bb username password

--The next step:
[Oracle@bys3 admin]$ Cat Sqlnet.ora
Sqlnet. Authentication_services= (All)
Test from OCM1 Host: Login error: ORA-12641:
[Oracle@ocm1 admin]$ Sqlplus Bys/bys@bys3
Sql*plus:release 10.2.0.1.0-production on Fri 17 11:27:29 2014
Copyright (c) 1982, +, Oracle. All rights reserved.
ERROR:
Ora-12641:authentication Service failed to initialize
At this point, the client or one of the server's Sqlnet.ora changed to Sqlnet.authentication_services= (NONE), you can connect-the same as the first step of the experiment.