Database Reference
In-Depth Information
■
this section covers the setup of an alternative solution that uses a lightweight open source dedicated proxy.
If you choose to use this option, make sure that you gain the consent of your network administrators.
Caution
This means we can run our own proxy server that doesn't require Cloud Control to know about Active Directory
authentication and still authenticate against the corporate proxy with all the corporate security rules in place.
To install, download and unzip the distribution to
/opt/ntlmaps
. If you are on RedHat or something similar, Python is
already available as part of the standard distribution. Otherwise, you'll also need to install Python. NTLMAPS uses a
configuration file,
server.cfg
. You'll need to enter values for the following:
PARENT_PROXY
: The IP address of the parent server
•
PARENT_PORT
: The port on which the parent listens
•
USER
: The configured Active Directory name
•
PASSWORD
: The configured AD password for the user
•
NT_DOMAIN
: The NT domain name
•
Once this is done, start the proxy server manually for the time being by executing the supplied script,
python main.py
. By default, NTLMAPS uses port 5865. This should probably be acceptable. Whichever route you
take, you should now configure Internet access for the OMS server(s) using the NTLMAPS address as the proxy
address in step 2 in the preceding “Configuring Proxy Server Access” section. Once the proxy is working OK, the next
step is to configure a Linux service by using
chkconfig
. The script I use is an open source script available in the code
repository for this topic.
Notifications
One of the major roles for Enterprise Manager is to trigger alerts when managed targets encounter an event that
requires attention. Classic examples of this occur when a web server is down or when a data store is running out of
space as data is added. Enterprise Manager splits this task into two distinct phases: alerting and notification. Both
areas are configurable from the Cloud Control menu bar.
The alert phase is concerned with recording the occurrence of a particular event, usually driven by a certain
metric. This information becomes visible on the target home page after processing by the management server.
The fact that alerts fire but do not necessarily raise alarms for administrators is a common cause of confusion for
users new to the product.
The notification phase, by contrast, is the process of sending the details of the alert by some method to allow an
appropriate administrator to respond to the alert condition. For example, a DBA might be paged to let her know that
a database's system tablespace is dangerously low on space and that she should add space to the tablespace urgently.
Notifications traditionally take place via e-mail, but they can also be routed via SNMP, perhaps to an operational
control center, by PL/SQL procedures that a DBA or database developer might write or by running an operating
system command (perhaps a shell script) on the management server.
Once you have successfully installed Enterprise Manager and while logged in using the
SYSMAN
account, one of
your first tasks should be to add a notification method that can be used to notify the administrators you set up. In this
example, you will use e-mail, because that is by far the most common method encountered in real installations.
To start the process, choose Setup
➤
Notifications
➤
Notification Methods, as shown in Figure
4-21
.
