Oracle EM error Solution

Oracle provides a Web-Based Enterprise Manager (EM.

First, enter

Http: // localhost: 1158/em

You can view the port in the/oraclehome/install/portlist. ini file. Different databases have different ports.
After logging on to em, the interface is displayed, but an error is reported: java. lang. Exception: Exception in sending Request: null. If many functions are unavailable, the system prompts you to log on again. Note: The database version here is Oracle 10g. Although Oracle 11g has been released, Oracle 10g is still used due to the company's project requirements and needs. Solution:

1. Find the following file
$ ORACLE_HOME \ db_1 \ $ HOSTNAME \ sysman \ config \ emd. properties
2. The default value of agentTZRegion is GMT, which can be changed to your time zone. For example:
AgentTZRegion = Asia/Shanghai
3. Stop dbconsole to make the time zone settings take effect and restart OracleDBConsole:
Run emctl stop dbconsole

However, I reported another error when running this command.
Environment variable ORACLE_SID not defined. Please define it.

In this case, we can set ORACLE_SID by running the following command.
Set oracle_sid = orcl

Then we can use
Emctl stop dbconsole
Emctl start dbconsole
To restart the OracleDBConsole: