Cisco Sg3008 Manual

							IP Configuration
DHCP Server
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•Mask—Enter one of following:
-Network Mask—Check and enter the pool’s network mask.
-Prefix Length—Check and enter the number of bits that comprise the 
address prefix.
•Address Pool Start—Enter the first IP address in the range of the network 
pool.
•Address Pool End—Enter the last IP address in the range of the network 
pool.
•Lease Duration—Enter the amount of time a DHCP client can use an IP 
address from this pool. You can configure a lease duration of up to 49,710 
days or an infinite duration.
-Infinite—The duration of the lease is unlimited.
-Days—The duration of the lease in number of days. The range is 0 to 
49710 days. 
-Hours—The number of hours in the lease. A days value must be supplied 
before an hours value can be added. 
-Minutes—The number of minutes in the lease. A days value and an hours 
value must be added before a minutes value can be added. 
•Default Router IP Address (Option 3)— Enter the default router for the DHCP 
client.
•Domain Name Server IP Address (Option 6)—Select one of the devices DNS 
servers (if already configured) or select Other and enter the IP address of 
the DNS server available to the DHCP client.
•Domain Name (Option 15)—Enter the domain name for a DHCP client. 
•NetBIOS WINS Server (Option 44)— Enter the NetBIOS WINS name server 
available to a DHCP client. 
•NetBIOS Node Type (Option 46)—Select how to resolve the NetBIOS name. 
Valid node types are:
-Hybrid—A hybrid combination of b-node and p-node is used. When 
configured to use h-node, a computer always tries p-node first and uses 
b-node only if p-node fails. This is the default. 
						

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-Mixed—A combination of b-node and p-node communications is used to 
register and resolve NetBIOS names. M-node first uses b-node; then, if 
necessary, p-node. M-node is typically not the best choice for larger 
networks because its preference for b-node Broadcasts increases 
network traffic.
-Peer-to-Peer—Point-to-point communications with a NetBIOS name 
server are used to register and resolve computer names to IP addresses.
-Broadcast—IP Broadcast messages are used to register and resolve 
NetBIOS names to IP addresses.
•SNTP Server IP Address (Option 4)— Select one of the device’s SNTP 
servers (if already configured) or select Other and enter the IP address of 
the time server for the DHCP client.
•File Server IP Address (siaddr)—Enter the IP address of the TFTP/SCP 
server from which the configuration file is downloaded. 
•File Server Host Name (sname)—Enter the name of the TFTP/SCP server. 
•Configuration File Name (file)—Enter the name of the file that is used as a 
configuration file.
Excluded Addresses
By default, the DHCP server assumes that all pool addresses in a pool may be 
assigned to clients. A single IP address or a range of IP addresses can be 
excluded. The excluded addresses are excluded from all DHCP pools.
To define an excluded address range:
STEP 1Click IP Configuration > IPv4 Management and Interfaces > DHCP Server > 
Excluded Addresses to display the Excluded Addresses page.
The previously-defined excluded IP addresses are displayed.
STEP  2To add a range of IP addresses to be excluded, click Add, and enter the fields:
•Start IP Address—First IP address in the range of excluded IP addresses.
•End IP Address—Last IP address in the range of excluded IP addresses.
Static Hosts
You might want to assign some DHCP clients a permanent IP address that never 
changes. This client is then known as a static host. 
						

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DHCP Server
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To manually allocate a permanent IP address to a specific client:
STEP 1Click IP Configuration > IPv4 Management and Interfaces > DHCP Server > Static 
Hosts to display the Static Hosts page.
The static hosts are displayed.
STEP 2 To add a static host, click Add, and enter the fields:
•IP Address—Enter the IP address that was statically assigned to the host.
•Host Name—Enter the host name, which can be a string of symbols and an 
integer. 
•Mask—Enter the static host’s network mask.
-Net work Mask—Check and enter the static host’s network mask.
-Prefix Length—Check and enter the number of bits that comprise the 
address prefix.
•Identifier Type—Set how to identify the specific static host.
-Client Identifier—Enter a unique identification of the client specified in 
hexadecimal notation, such as: 01b60819681172.
or:
-MAC Address—Enter the MAC address of the client.
•Client Name—Enter the name of the static host, using a standard set of ASCII 
characters. The client name must not include the domain name. 
•Default Router IP Address (Option 3)— Enter the default router for the static 
host.
•Domain Name Server IP Address (Option 6)—Select one of the devices DNS 
servers (if already configured) or select Other and enter the IP address of 
the DNS server available to the DHCP client.
•Domain Name (Option 15)—Enter the domain name for the static host. 
•NetBIOS WINS Server (Option 44)— Enter the NetBIOS WINS name server 
available to the static host. 
•NetBIOS Node Type (Option 46)—Select how to resolve the NetBIOS name. 
Valid node types are: 
						

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-Hybrid—A hybrid combination of b-node and p-node is used. When 
configured to use h-node, a computer always tries p-node first and uses 
b-node only if p-node fails. This is the default.
-Mixed—A combination of b-node and p-node communications is used to 
register and resolve NetBIOS names. M-node first uses b-node; then, if 
necessary, p-node. M-node is typically not the best choice for larger 
networks because its preference for b-node Broadcasts increases 
network traffic.
-Peer-to-Peer—Point-to-point communications with a NetBIOS name 
server are used to register and resolve computer names to IP addresses.
-Broadcast—IP Broadcast messages are used to register and resolve 
NetBIOS names to IP addresses.
•SNTP Server IP Address (Option 4)— Select one of the device’s SNTP 
servers (if already configured) or select Other and enter the IP address of 
the time server for the DHCP client.
•File Server IP Address (siaddr)—Enter the IP address of the TFTP/SCP 
server from which the configuration file is downloaded. 
•File Server Host Name (sname)—Enter the name of the TFTP/SCP server. 
•Configuration File Name (file)—Enter the name of the file that is used as a 
configuration file.
DHCP Options
When the device is acting as a DHCP server, the DHCP options can be configured 
using the HEX option. A description of these options can be found in RFC2131.
The configuration of these options determines the reply that is sent to DHCP 
clients whose packets include a request (using option 55) for the configured DHCP 
options.
The options that are configured specifically on the DHCP Server >Network Pools 
and the DHCP Server >Static Hosts pages (Option 3-6, 15, 44, 46, 66, 67) cannot 
be configured using the DHCP Options page.
Example: The DHCP option 66 is configured with the name of a TFTP server in the 
DHCP Options page. When a client DHCP packet is received containing option 66, 
the TFTP server is returned as the value of option 66. 
						

							IP Configuration
DHCP Server
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To configure one or more DHCP options:
STEP 1Click IP Configuration > IPv4 Management and Interfaces > DHCP Server > DHCP 
Options.
The previously-configured DHCP options are displayed..
STEP  2To configure an option that has not been configured yet and enter the field:
•DHCP Server Pool Name—Select one of the pool of network addresses 
defined in the Network Pools page.
STEP  3Click Add and enter the fields:
•Code— Enter the DHCP option code.
•Ty p e —  The radio buttons for this field, change according to the type of the 
DHCP option’s parameter. Select one of the following codes and enter the 
value for the DHCP options parameter:
-Hex—Select if you want to enter the hex value of the parameter for the 
DHCP option. A hex value can be provided in place of any other type of 
value. For instance, you can provide a hex value of an IP address instead 
of the IP address itself.
No validation is made of the hex value, therefore if you enter a HEX value, 
which represents an illegal value, no error is provided, and the client 
might not be able to handle the DHCP packet from the server.
-IP—Select if you want to enter an IP address when this is relevant for the 
DHCP option selected.
-IP List—Enter list of IP addresses separated by commas.
-Integer—Select if you want to enter an integer value of the parameter for 
the DHCP option selected.
-Boolean—Select if the parameter for the DHCP option selected is 
Boolean.
•Boolean Value— If the type was Boolean, select the value to be returned: 
Tr u e or False.
•Va lue —  If the type is not Boolean, enter the value to be sent for this code.
•Description— Enter a text description for documentation purposes. 
						

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DHCP Server
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Address Binding
Use the Address Binding page to view and remove the IP addresses allocated by 
the device and their corresponding MAC addresses. 
To view and/or remove address bindings:
STEP 1Click IP Configuration > IPv4 Management and Interfaces > DHCP Server > 
Address Binding to display the Address Binding page. 
The following fields for the address bindings are displayed:
•IP Address—The IP addresses of the DHCP clients.
•Address Type— Whether the address of the DHCP client appears as a MAC 
address or using a client identifier.
•MAC Address/Client Identifier—A unique identification of the client 
specified as a MAC Address or in hexadecimal notation, e.g., 
01b60819681172.
•Lease Expiration—The lease expiration date and time of the host’s IP 
address or Infinite is such was the lease duration defined.
•Ty p e—The manner in which the IP address was assigned to the client. The 
possible options are:
-Static—The hardware address of the host was mapped to an IP address.
-Dynamic—The IP address, obtained dynamically from the device, is 
owned by the client for a specified period of time. The IP address is 
revoked at the end of this period, at which time the client must request 
another IP address. 
•State—The possible options are:
-Allocated—IP address has been allocated. When a static-host is 
configured, its state is allocated.
-Declined—IP address was offered but not accepted, therefore it is not 
allocated.
-Expired—The lease of the IP address has expired. 
-Pre-Allocated—An entry will be in pre-allocated state from the time 
between the offer and the time that the DHCP ACK is sent from the client. 
Then it becomes allocated. 
						

							IP Configuration
IPv6 Management and Interfaces
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IPv6 Management and Interfaces
The Internet Protocol version 6 (IPv6) is a network-layer protocol for packet-
switched internetworks. IPv6 was designed to replace IPv4, the predominantly 
deployed Internet protocol. 
IPv6 introduces greater flexibility in assigning IP addresses, because the address 
size increases from 32-bit to 128-bit addresses. IPv6 addresses are written as 
eight groups of four hexadecimal digits, for example 
FE80:0000:0000:0000:0000:9C00:876A:130B. The abbreviated form, in which a 
group of zeroes can be left out, and replaced with ::, is also acceptable, for 
example, ::-FE80::9C00:876A:130B.
IPv6 nodes require an intermediary mapping mechanism to communicate with 
other IPv6 nodes over an IPv4-only network. This mechanism, called a tunnel, 
enables IPv6-only hosts to reach IPv4 services, and enables isolated IPv6 hosts 
and networks to reach an IPv6 node over the IPv4 infrastructure. 
Tunneling uses either an ISATAP or manual mechanism (see IPv6 Tunnel). 
Tunneling treats the IPv4 network as a virtual IPv6 local link, with mappings from 
each IPv4 address to a link local IPv6 address.
The device detects IPv6 frames by the IPv6 Ethertype.
IPv6 Global Configuration
To define IPv6 global parameters and DHCPv6 client settings:
STEP 1In Layer 2 system mode, click Administration > Management Interface > IPv6 
Global Configuration.
In Layer 3 system mode, click IP Configuration > IPv6 Management and 
Interfaces > IPv6 Global Configuration.
STEP  2Enter values for the following fields:
•ICMPv6 Rate Limit Interval—Enter how often the ICMP error messages are 
generated.
•ICMPv6 Rate Limit Bucket Size—Enter the maximum number of ICMP error 
messages that can be sent by the device per interval. 
						

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DHCPv6 Client Settings 
•Unique Identifier (DUID) Format—This is the identifier of the DHCP client 
that is used by the DHCP server to locate the client. It can be in one of the 
following formats :
-Link-Layer—(Default). If you select this option, the MAC address of the 
device is used.
-Enterprise Number—If you select this option, enter the following fields.
•Enterprise Number—The vendors registered Private Enterprise number as 
maintained by IANA.
•Identifier—The vendor-defined hex string (up to 64 hex characters). If the 
number of the character is not even, a zero is added at the right. Each 2 hex 
characters can be separated by a period or colon.
•DHCPv6 Unique Identifier (DUID)—Displays the identifier selected.
IPv6 Interface
An IPv6 interface can be configured on a port, LAG, VLAN, loopback interface or 
tunnel. 
A tunnel interface is configured with an IPv6 address based on the settings 
defined in the IPv6 Tunnel page. 
To define an IPv6 interface: 
STEP 1In Layer 2 system mode, click Administration > Management Interface > IPv6 
Interfaces. 
In Layer 3 system mode, click IP Configuration > IPv6 Management and 
Interfaces > IPv6 Interfaces.
STEP  2Click Add to add a new interface on which interface IPv6 is enabled.
STEP  3Enter the fields:
•IPv6 Interface—Select a specific port, LAG, VLAN, or ISATAP tunnel for the 
IPv6 address. 
STEP  4To configure the interface as a DHCPv6 client, meaning to enable the interface to 
receive information from the DHCPv6 server, such as: SNTP configuration and 
DNS information, enter the DHCPv6 Client fields:  
						

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•Stateless—Select to enable the interface as a stateless DHCPv6 client. This 
enables reception of configuration information from a DHCP server.
•Minimum Information Refresh Time—This value is used to put a floor on 
the refresh time value. If the server sends a refresh time option that is less 
than this value, this value is used instead. Select either Infinite (no refresh 
unless the server sends this option) or User Defined to set a value.
•Information Refresh Time—This value indicates how often the device will 
refresh information received from the DHCPv6 server. If this option is not 
received from the server, the value entered here is used. Select either 
Infinite (no refresh unless the server sends this option) or User Defined to 
set a value.
STEP  5To configure additional IPv6 parameters, enter the following fields:
•IPv6 Address Auto Configuration—Select to enable automatic address 
configuration from router advertisements sent by neighbors. 
NOTEThe device does not support stateful address auto configuration from 
a DHCPv6 server. 
•Number of DAD Attempts—Enter the number of consecutive neighbor 
solicitation messages that are sent while Duplicate Address Detection (DAD) 
is performed on the interface’s Unicast IPv6 addresses. DAD verifies the 
uniqueness of a new Unicast IPv6 address before it is assigned. New 
addresses remain in a tentative state during DAD verification. Entering 0 in 
this field disables duplicate address detection processing on the specified 
interface. Entering 1 in this field indicates a single transmission without 
follow-up transmissions.
•Send ICMPv6 Messages—Enable generating unreachable destination 
messages.
STEP  6Click Apply to enable IPv6 processing on the selected interface. Regular IPv6 
interfaces have the following addresses automatically configured:
•Link local address using EUI-64 format interface ID based on a device’s MAC 
address
•All node link local Multicast addresses (FF02::1)
•Solicited-Node Multicast address (format FF02::1:FFXX:XXXX)
STEP  7Click IPv6 Address Table to manually assign IPv6 addresses to the interface, if 
required. This page is described in the Defining IPv6 Addresses section. 
						

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STEP  8Press the Restart button to initiate refresh of the stateless information received 
from the DHCPv6 server.
DHCPv6 Client Details
The DHCPv6 Client Details button displays information received on the interface 
from a DHCPv6 server.
It is active when the interface selected is defined as a DHCPv6 stateless client.
When the button is pressed, it displays the following fields (for the information that 
was received from the DHCP server):
•DHCPv6 Operational Mode—This displays Enabled if the following 
conditions are fulfilled:
-The interface is Up.
-IPv6 is enabled on it.
-DHCPv6 stateless client is enabled on it.
•Stateless Service—Is the client defined as stateless (receives configuration 
information from a DHCP server) or not.
•DHCPv6 Server Address—Address of DHCPv6 server.
•DHCPv6 Server DUID—Unique identifier of the DHCPv6 server.
•DHCPv6 Server Preference—Priority of this DHCPv6 server.
•Information Minimum Refresh Time— See above.
•Information Refresh Time—See above.
•Received Information Refresh Time—Refresh time received from DHCPv6 
server.
•Remaining Information Refresh Time—Remaining time until next refresh.
•DNS Servers—List of DNS servers received from the DHCPv6 server.
•DNS Domain Search List—List of domains received from the DHCPv6 
server.
•SNTP Servers—List of SNTP servers received from the DHCPv6 server.
•POSIX Timezone String—Timezone received from the DHCPv6 server.
•Configuration Server—Server containing configuration file received from 
the DHCPv6 server.