RUGGEDCOM ROX II
CLI User Guide
Chapter 6
Security
Managing Firewalls
183
no
admin known-hosts server-identification
name
Where
name
is the unique name of the server.
3. Type
commit
and press
Enter
to save the changes, or type
revert
and press
Enter
to abort.
Section 6.9
Managing Firewalls
Firewalls are software systems designed to prevent unauthorized access to or from private networks. Firewalls are
most often used to prevent unauthorized Internet users from accessing private networks (Intranets) connected to
the Internet.
When the RUGGEDCOM ROX II firewall is enabled, the router serves as a gateway machine through which all
messages entering or leaving the Intranet pass. The router examines each message and blocks those that do not
meet the specified security criteria. The router also acts as a proxy, preventing direct communication between
computers on the Internet and Intranet. Proxy servers can filter the kinds of communication that are allowed
between two computers and perform address translation.
NOTE
In general, the RUGGEDCOM ROX II firewall implementation will maintain established connections.
This applies when adding, deleting, or changing rules, and also when adding, deleting, or changing
policies. When applying new, or modified, rules or policies, previous traffic seen by the router might
still be considered as having valid connections by the connection tracking table. For instance:
a. A rule for the TCP and UDP protocols is applied.
b. The router sees both TCP and UDP traffic that qualifies for NAT.
c. The rule is then modified to allow only UDP.
d. The router will still see TCP packets (i.e. retransmission packets).
If required, reboot the router to flush all existing connection streams.
RUGGEDCOM ROX II employs a stateful firewall system known as netfilter, a subsystem of the Linux kernel that
provides the ability to examine IP packets on a per-session basis.
For more information about firewalls, refer to
Section 6.9.1, “Firewall Concepts”
CONTENTS
•
Section 6.9.1, “Firewall Concepts”
•
Section 6.9.2, “Viewing a List of Firewalls”
•
Section 6.9.3, “Adding a Firewall”
•
Section 6.9.4, “Deleting a Firewall”
•
Section 6.9.5, “Working with Multiple Firewall Configurations”
•
Section 6.9.6, “Configuring the Firewall for a VPN”
•
Section 6.9.7, “Configuring the Firewall for a VPN in a DMZ”
•
Section 6.9.8, “Configuring Netfilter”
•
Section 6.9.9, “Managing Zones”
•
Содержание RUGGEDCOM ROX II
Страница 2: ...RUGGEDCOM ROX II CLI User Guide ii ...
Страница 4: ...RUGGEDCOM ROX II CLI User Guide iv ...
Страница 39: ...RUGGEDCOM ROX II CLI User Guide Table of Contents xxxix 19 5 VLANs 752 ...
Страница 40: ...Table of Contents RUGGEDCOM ROX II CLI User Guide xl ...
Страница 46: ...Preface RUGGEDCOM ROX II CLI User Guide xlvi Customer Support ...
Страница 96: ...Chapter 2 Using RUGGEDCOM ROX II RUGGEDCOM ROX II CLI User Guide 50 Accessing Maintenance Mode ...
Страница 170: ...Chapter 5 System Administration RUGGEDCOM ROX II CLI User Guide 124 Deleting a Scheduled Job ...
Страница 256: ...Chapter 6 Security RUGGEDCOM ROX II CLI User Guide 210 Enabling Disabling a Firewall ...
Страница 402: ...Chapter 11 Wireless RUGGEDCOM ROX II CLI User Guide 356 Managing Cellular Modem Profiles ...
Страница 646: ...Chapter 13 Unicast and Multicast Routing RUGGEDCOM ROX II CLI User Guide 600 Deleting a Multicast Group Prefix ...
Страница 732: ...Chapter 15 Network Discovery and Management RUGGEDCOM ROX II CLI User Guide 686 Viewing NETCONF Statistics ...
Страница 790: ...Chapter 17 Time Services RUGGEDCOM ROX II CLI User Guide 744 Deleting a Broadcast Multicast Address ...