D-Link DFL-1600 - Security Appliance, Руководство пользователя

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2.7. Maintenance
2.7.1. Auto-Update Mechanism
A number of the NetDefendOS security features rely on external servers for automatic updates and
content filtering. The Intrusion Prevention and Detection system and Anti-Virus modules require
access to updated signature databases in order to provide protection against the latest threats.
To facilitate the Auto-Update feature D-Link maintains a global infrastructure of servers providing
update services for NetDefend Firewalls. To ensure availability and low response times,
NetDefendOS employs a mechanism for automatically selecting the most appropriate server to
supply updates.
For more details on these features see the following sections:
• Section 6.5, “Intrusion Detection and Prevention”
• Section 6.4, “Anti-Virus Scanning”
• Section 6.3, “Web Content Filtering”
2.7.2. Backing Up Configurations
The administrator has the ability to take a snapshot of a NetDefendOS system at a given point in
time and restore it when necessary. The snapshot can be of two types:
• A Configuration Backup
This is the entire current NetDefendOS configuration saved into a single file. It does not include
the installed NetDefendOS version. This is useful when restoring only the configuration.
It is important to create, at the minimum, a configuration backup on a regular basis so that a
configuration can be easily recreated in the event of hardware replacement. The alternative is to
recreate a configuration by manually adding its contents, piece by piece.
• A System Backup
This a complete backup of both the configuration and the installed NetDefendOS software saved
into a single file. This is useful if restoring. both the configuration and the NetDefendOS version
upgraded.
A complete system backup is a much larger file than a configuration backup and can be many
megabytes, it is therefore not recommended to perform this on a regular basis because of the
time involved. However, it is recommended to create this at least once when the NetDefend
Firewall is initially configured and goes live. This is because it a full system backup makes it
easier to restore the current configuration on new hardware.
Warning: Do not upload a system backup to dissimilar hardware
Do not try to upload a full system backup (configuration plus NetDefendOS) to
hardware that is not the same model as the original.
This will cause the configuration to be automatically activated and the hardware
restarted, with the possibility that NetDefendOS becomes unreachable. Upload of full
system backups must be done to similar hardware since there is no opportunity to
change the configuration before it is activated.
Version Compatability
2.7. Maintenance Chapter 2. Management and Maintenance
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