Red Hat DIRECTORY SERVER 8.0, Руководство администратора

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Creating and Maintaining Database Links
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• It is possible for old, unencrypted data to persist in the server's database page pool
backing file, even after a successful re-import with encryption. To remove this data, stop
the server and delete the
db/guardian
file, then re-start the server. This will force
recovery, a side-effect of which is deleting the backing file. However, it is possible that
the data from the deleted file could still be recovered from the hard drive unless steps
are taken to overwrite the disk blocks that it occupied.
• After enabling encryption and importing data, be sure to delete the LDIF file because it
contains plain text values for the now-encrypted data. Ensure that the disk blocks that it
occupied are overwritten.
• The unencrypted data previously stored in the server's database may persist on disk
after a successful re-import with encryption. This is because the old database files
are deleted as part of the import process. Ensure that the disk blocks that those files
occupied are overwritten.
• Data stored in the server's replication log database is never encrypted; therefore, care
should be taken to protect those files if replication is used.
• The server does not attempt to protect unencrypted data stored in memory. This data
may be copied into a system page file by the operating system. For this reason, ensure
that any page or swap files are adequately protected.
3.3. Creating and Maintaining Database Links
Chaining
means that a server contacts other servers on behalf of a client application and then returns
the combined results. Chaining is implemented through a
database link
, which points to data stored
remotely. When a client application requests data from a database link, the database link retrieves the
data from the remote database and returns it to the client.
Section 13.5, “Monitoring Database Link Activity”
covers how to monitor database link activity.
•
Section 3.3.1, “Configuring the Chaining Policy”
•
Section 3.3.2, “Creating a New Database Link”
•
Section 3.3.3, “Chaining Using SSL”
•
Section 3.3.4, “Maintaining Database Links”
•
Section 3.3.5, “Database Links and Access Control Evaluation”
•
Section 3.3.6, “Advanced Feature: Tuning Database Link Performance”
•
Section 3.3.7, “Advanced Feature: Configuring Cascading Chaining”
3.3.1. Configuring the Chaining Policy
These procedures describe configuring how Directory Server chains requests made by client
applications to Directory Servers that contain database links. This chaining policy applies to all
database links created on Directory Server.