Assigned DNS Servers
The lease granted by a DHCPv6 server can contain up to three IPv6 addresses of DNSv6 servers.
However, NetDefendOS will only use the first and second of these which are sometimes known
as the
Primary
, and
Secondary
servers. If a third server is present in the lease it will be ignored.
The DNSv6 addresses obtained from the DHCP server will be stored in two properties of the
interface configuration object which are called
DHCPv6DNS1
and
DHCPv6DNS2
.
Created DNS Address Objects
For the first DNSv6 server address in a lease, NetDefendOS will automatically create a new IPv6
address book object with the name
<interface>_dns6_<num>
, where
<interface>
is the interface
receiving the lease and
<num>
is the order number of the DNSv6 server in the lease.
For example, if the interface receiving the DHCPv6 lease is the
wan
interface then the address
book object created for the first lease will be named
wan_dns6_1
. If the lease contains a second
DNSv6 server address, this will be called
wan_dns6_2
and so on.
The DNSv6 server addresses can be configured statically for NetDefendOS. If this is done, these
manually configured addresses take precedence over addresses received in a lease. However,
NetDefendOS will still automatically create the address book objects of the form
<interface>_dns6_<num>
for each DHCPv6 server address received in the lease. This precedence
of statically defined DNS addresses is discussed further in
.
Behavior on Lease Expiry
When a DHCP lease ends and is not renewed, any address book objects created by the DHCPv6
mechanism will remain in the address book. However, the values of the address book objects
associated with an interface will be affected as follows:
•
Network and gateway objects will retain the values that were last allocated by DHCPv6.
•
All other objects will be set to the IPv6
unspecified address
(
::/128
).
Example 5.6. DHCPv6 Client Setup
This example shows how to enable DHCPv6 on the
wan
interface. It is assumed that IPv6 has
already been enabled for the interface.
Command-Line Interface
gw-world:/> set Interface Ethernet wan DHCPv6Enabled=Yes
Web Interface
1.
Go to: Network > Interfaces and VPN > Ethernet
2.
Select the wan interface
3.
Select Enable DHCPv6 Client
Chapter 5: DHCP Services
413
Summary of Contents for NetDefendOS
Page 30: ...Figure 1 3 Packet Flow Schematic Part III Chapter 1 NetDefendOS Overview 30 ...
Page 32: ...Chapter 1 NetDefendOS Overview 32 ...
Page 144: ...Chapter 2 Management and Maintenance 144 ...
Page 284: ...Chapter 3 Fundamentals 284 ...
Page 392: ...Chapter 4 Routing 392 ...
Page 419: ... Host 2001 DB8 1 MAC 00 90 12 13 14 15 5 Click OK Chapter 5 DHCP Services 419 ...
Page 420: ...Chapter 5 DHCP Services 420 ...
Page 573: ...Chapter 6 Security Mechanisms 573 ...
Page 607: ...Chapter 7 Address Translation 607 ...
Page 666: ...Chapter 8 User Authentication 666 ...
Page 775: ...Chapter 9 VPN 775 ...
Page 819: ...Chapter 10 Traffic Management 819 ...
Page 842: ...Chapter 11 High Availability 842 ...
Page 866: ...Default Enabled Chapter 13 Advanced Settings 866 ...
Page 879: ...Chapter 13 Advanced Settings 879 ...