Cisco Sg3008 Manual

							IP Configuration
IPv6 Management and Interfaces
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STEP 1Click IP Configuration > IPv6 Management and Interfaces > DHCPv6 Relay > 
Global Destinations.
STEP  2To add a default DHCPv6 server, click Add.
STEP  3Enter the fields:
•IPv6 Address Type—Enter the type of the destination address to which 
client messages are forwarded. The address type can be Link Local, Global 
or Multicast (All_DHCP_Relay_Agents_and_Servers).
•DHCPv6 Server IP Address—Enter the address of the DHCPv6 server to 
which packets are forwarded.
•Destination IPv6 Interface—Enter the interface on which packets are 
transmitted when the address type of the DHCPv6 server is Link Local or 
Multicast.
STEP  4Click Apply. The Running Configuration file is updated.
Interface Settings
To enable the DHCPv6 Relay feature on an interface and to configure a list of 
DHCPv6 servers to which DHCPv6 packets are relayed when they are received on 
this interface.
STEP 1Click IP Configuration > IPv6 Management and Interfaces > DHCPv6 Relay > 
Interface Settings.
STEP  2To enable DHCPv6 on an interface and optionally add a DHCPv6 server for an 
interface, click Add.
Enter the fields:
•Source Interface—Select the interface (port, LAG, VLAN or tunnel) for 
which DHCPv6 Relay is enabled.
•Use Global Destinations Only—Select to forward packets to the DHCPv6 
global destination servers only.
•IPv6 Address Type—Enter the type of the destination address to which 
client messages are forwarded. The address type can be Link Local, Global 
or Multicast (All_DHCP_Relay_Agents_and_Servers).
•DHCPv6 Server IP Address—Enter the address of the DHCPv6 server to 
which packets are forwarded. 
						

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•IPv6 Interface—Enter the interface on which packets are transmitted when 
the address type of the DHCPv6 server is Link Local or Multicast.
STEP  3Click Apply. The Running Configuration file is updated.
Domain Name
The Domain Name System (DNS) translates domain names into IP addresses for 
the purpose of locating and addressing hosts.
As a DNS client, the device resolves domain names to IP addresses through the 
use of one or more configured DNS servers. 
DNS Settings
Use the DNS Settings page to enable the DNS feature, configure the DNS servers 
and set the default domain used by the device. 
STEP 1Click IP Configuration > Domain Name > DNS Settings.
STEP  2Enter the parameters.
•DNS—Select to designate the device as a DNS client, which can resolve 
DNS names into IP addresses through one or more configured DNS servers.
•Polling Retries—Enter the number of times to send a DNS query to a DNS 
server until the device decides that the DNS server does not exist.
•Polling Timeout—Enter the number of seconds that the device will wait for 
a response to a DNS query. 
•Polling Interval—Enter how often (in seconds) the device sends DNS query 
packets after the number of retries has been exhausted. 
-Use Default—Select to use the default value. 
This value = 2*(Polling Retries + 1)* Polling Timeout
-User Defined—Select to enter a user-defined value.
•Default Parameters—Enter the following default parameters:
-Default Domain Name—Enter the DNS domain name used to complete 
unqualified host names. The device appends this to all non-fully qualified 
domain names (NFQDNs) turning them into FQDNs.  
						

							IP Configuration
Domain Name
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NOTEDo not include the initial period that separates an unqualified name 
from the domain name (like cisco.com).
-D H C P  D o m a i n  S e a r c h  L i s t—Click Details to view the list of DNS servers 
configured on the device.
STEP  3Click Apply. The Running Configuration file is updated.
DNS Server Table: The following fields are displayed for each DNS server 
configured:
•DNS Server—The IP address of the DNS server. 
•Preference—Each server has a preference value, a lower value means a 
higher chance of being used. 
•Source—Source of the server ’s IP address (static or DHCPv4 or DHCPv6)
•Interface—Interface of the server ’s IP address.
STEP  4Up to eight DNS servers can be defined. To add a DNS server, click Add.
Enter the parameters.
•IP Version—Select Version 6 for IPv6 or Version 4 for IPv4.
•IPv6 Address Type—Select the IPv6 address type (if IPv6 is used). The 
options are:
-Link Local—The IPv6 address uniquely identifies hosts on a single 
network link. A link local address has a prefix of FE80, is not routable, and 
can be used for communication only on the local network. Only one link 
local address is supported. If a link local address exists on the interface, 
this entry replaces the address in the configuration.
-Global—The IPv6 address is a global Unicast IPV6 type that is visible and 
reachable from other networks. 
•Link Local Interface—If the IPv6 address type is Link Local, select the 
interface through which it is received.
•DNS Server IP Address—Enter the DNS server IP address.
•Preference—Select a value that determines the order in which the domains 
are used (from low to high). This effectively determines the order in which 
unqualified names are completed during DNS queries. 
STEP  5Click Apply. The DNS server is saved to the Running Configuration file. 
						

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Search List
The search list can contain one static entry defined by the user the DNS Settings 
page and dynamic entries received from DHCPv4 and DHCPv6 servers.
To view the domain names that have been configured on the device:
STEP 1Click IP Configuration > Domain Name > Search List.
The following fields are displayed for each DNS server configured on the device.
•Domain Name—Name of domain that can be used on the device. 
•Source—Source of the server ’s IP address (static or DHCPv4 or DHCPv6) 
for this domain.
•Interface—Interface of the server ’s IP address for this domain.
•Preference—This is the order in which the domains are used (from low to 
high). This effectively determines the order in which unqualified names are 
completed during DNS queries.
Host Mapping
Host name/IP address mappings are stored in the Host Mapping Table (DNS 
cache). 
This cache can contain the following type of entries:
•Static Entries—These are mapping pairs that were manually added to the 
cache. There can be up to 64 static entries.
•Dynamic Entries—These are mapping pairs that were either added by the 
system as a result of being used by the user, or and an entry for each IP 
address configured on the device by DHCP. There can be 256 dynamic 
entries. 
Name resolution always begins by checking static entries, continues by checking 
the dynamic entries, and ends by sending requests to the external DNS server.
Eight IP addresses are supported per DNS server per host name. 
						

							IP Configuration
Domain Name
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To add a host name and its IP address:
STEP 1Click IP Configuration > Domain Name System > Host Mapping.
STEP  2If required, select the Clear Table option to clear some or all of the entries in the 
Host Mapping Table. 
•Static Only—Deletes the static hosts. 
•Dynamic Only—Deletes the dynamic hosts. 
•All Dynamic & Static—Deletes the static and dynamic hosts. 
The Host Mapping Table displays the following fields:
•Host Name—User-defined host name or fully-qualified name. 
•IP Address—The host IP address.
•IP Version—IP version of the host IP address.
•Type—Is this a Dynamic or Static entry to the cache. 
•Status— Displays the results of attempts to access the host
-
OK—Attempt succeeded.
-
Negative Cache—Attempt failed, do not try again.
-
No Response—There was no response, but system can try again in 
future.
•TTL— If this is a dynamic entry, how long will it remain in the cache.
•Remaining T TL— If this is a dynamic entry, how much longer will it remain in 
the cache.
STEP  3To add a host mapping, click Add.
STEP  4Enter the parameters.
•IP Version—Select Version 6 for IP v6 or Version 4 for IP v4.
•IPv6 Address Type—Select the IPv6 address type (if IPv6 is used). The 
options are: 
						

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-Link Local—The IPv6 address uniquely identifies hosts on a single 
network link. A link local address has a prefix of FE80, is not routable, and 
can be used for communication only on the local network. Only one link 
local address is supported. If a link local address exists on the interface, 
this entry replaces the address in the configuration.
-Global—The IPv6 address is a global Unicast IPV6 type that is visible and 
reachable from other networks. 
•Link Local Interface—If the IPv6 address type is Link Local, select the 
interface through which it is received.
•Host Name—Enter a user-defined host name or fully-qualified name. Host 
names are restricted to the ASCII letters A through Z (case-insensitive), the 
digits 0 through 9, the underscore and the hyphen. A period (.) is used to 
separate labels.
•IP Address(es)—Enter a single address or up to eight associated IP 
addresses (IPv4 or IPv6).
You can select the Clear Table option to clear some or all of the entries in the Host 
Mapping Table. 
•Static Only—Deletes the static hosts. 
•Dynamic Only—Deletes the dynamic hosts. 
•All Dynamic & Static—Deletes the static and dynamic hosts.  
						

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