Basic Firewall - Cobalt Digital Inc COBALT Qube 3 User Manual

Basic Firewall

For more information on configuring the firewall, see "Basic Firewall" on
page 149.
For the definitions of the policies, see "Policy definitions" on page 153.
A firewall provides network security through a set of rules that restrict the flow of
information between your Qube 3 and your network. It is also used to control the
information that your Qube 3 allows to pass between different networks (such as
your company's intranet and the public Internet.
When information is transmitted between your Qube 3 server and a network (for
example, during an FTP file transfer or when fetching a Web page), the
information is divided into small blocks of data called packets. Each packet
contains a header which is used to direct the packet to its destination. The header
contains information such as the destination address and source address of the
packet, and indicates the software program that should receive the packet.
The Qube 3 ships with a type of firewall that allows you to accept or reject
packets based on the information found in the header of a packet. This is known
as an IP-packet-filtering firewall.
The type of IP-packet-filtering firewall implemented on the Qube 3 is the
standard ipchains firewall system which is compiled into the Linux kernel. You
can configure the ipchains firewall through the Qube 3's browser-based Server
Desktop.
Caution: Basic Firewall is an advanced feature of your Qube 3
server. This feature is not recommended for novice users.
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Note: The Web Caching feature on your Qube 3 (available on the
Qube 3 Business Edition and Professional Edition only) relies on
the Basic Firewall feature to operate. If you enable the Web
Caching feature, the Basic Firewall feature is enabled
automatically.
If you disable the Basic Firewall feature, the Web Caching feature
is still enabled but will not function. To ensure that the Web
Caching feature is functioning, re-enable the Basic Firewall feature.
For more information, see "Web Caching" on page 60.
Cobalt Qube 3 User Manual
Basic Firewall
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