Cisco Sg2008 Manual

							Port Management
Configuring Port Settings
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•Administrative Duplex Mode—If Auto Negotiation is disabled, select Half 
for half-duplex or Full for full-duplex operation.
•Admin Advertisement—If Autonegotiation is enabled, select the highest 
port speed and duplex setting that you want the port to negotiate. If you 
select Max Capacity, the port autonegotiates up to the highest port speed 
and duplex setting supported by hardware.
•Flow Control—Select to enable IEEE 802.3x flow control. Flow control 
reduces data loss when the port cannot keep up with the number of frames 
being switched. When enabled, the switch can send a PAUSE frame to stop 
traffic on a port if the amount of memory used by packets on the port 
exceeds a preconfigured threshold. The paused port does not forward 
packets for the period of time specified in the PAUSE frame. When the 
PAUSE frame time elapses or memory utilization falls below a specified low 
threshold, the switch enables the port to again transmit frames. When the 
mode is set to half–duplex, back pressure is exerted; however, we 
recommend that Flow Control be enabled.
•Member in LAG—Indicates whether the port is a member of a Link 
Aggregation Group. See Link Aggregation for information on configuring 
LAGs.
•MTU—Specify the maximum transmission unit size in bytes. The default 
MTU is 1518 and the range is between 1518 and  bytes.
STEP  4Click Apply and then click Close. Your changes are saved to the Running 
Configuration. 
						

							Port Management
Link Aggregation
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Link Aggregation
Link Aggregation allows one or more full-duplex Ethernet links to be aggregated 
together to form a Link Aggregation Group (LAG). The switch treats the LAG as if it 
is a single physical port, with improved fault tolerance and load- sharing capability.
A LAG interface can be either static or dynamic:
•Static LAG—Ports are assigned to a LAG directly by the administrator. The 
ports remain dedicated LAG members until configured otherwise.
•Dynamic LAG—A dynamic LAG is configured with one or more candidate 
ports. The LAG is formed by exchanging Link Aggregation Control Protocol 
Data Units with the remote device connecting to the candidate ports. When 
formed, the LAG might include only a subset of the eligible ports, 
depending on the port number limitations for LAGs and other factors. 
Candidate ports that are not selected as active member ports of a LAG are 
standby ports. A standby port may be selected as an active member when 
an active port in the same LAG fails.
The following topics provide additional information on the configuration pages 
available in the Port Management > Link Aggregation menu:
•Configuring LAGs
•Configuring LAG Settings
•Configuring LACP
Configuring LAGs
The switch supports up to 4 LAGs, with 8 ports per LAG. Use the LAG 
Management page to assign ports to LAGs and LACPs.
To display this page, click Port Management > Link Aggregation > LAG 
Management in the navigation window. 
Four dynamic LAGs are preconfigured by default named ch1 through ch4. They 
have no port members and are disabled.
You can add or remove ports to or from a LAG without disrupting traffic on the 
LAG.  
						

							Port Management
Link Aggregation
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LAGs can be assigned membership in VLANs; however, individual ports lose their 
individual VLAN memberships when they become LAG members. When a port is 
removed from a LAG, it rejoins the VLANs that it previously belong to as specified 
in the startup configuration.
To configure a LAG:
STEP 1Select a LAG to configure, and then click Edit.
STEP  2Specify the following for the selected LAG:
•LAG Name—Enter up to 15 alphanumeric characters to identify the LAG.
•Type—Select Static to manually assign ports to the LAG. Select Dynamic to 
enable the ports to exchange LACPDUs to dynamically form the LAG.
•Port List/LAG Member—To add or remove ports from a static LAG, select 
each port and click the left or right arrow to move it between the Port and 
LAG Member lists.
STEP  3Click Apply and then click Close. Your changes are saved to the Running 
Configuration. 
Configuring LAG Settings
You can use the LAG Settings page to administratively enable or disable a LAG 
and configure load balancing settings.
To configure LAG settings:
STEP 1Click Port Management > Link Aggregation > LAG Settings in the navigation 
window.
The LAG Settings Table lists each available LAG.
STEP  2Select a LAG to configure, and then click Edit.
STEP  3Specify the following for the selected LAG:
•Administrative Status—Select Up or Down to administratively enable or 
disable the LAG. When a LAG is disabled, its member ports operate as 
standalone physical ports. 
						

							Port Management
Link Aggregation
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•Load Balance Algorithm—Select one of the options to enable the switch to 
load-balance outgoing packets among member ports of a LAG. The switch 
selects one of the links in the channel for transmitting specific packets. The 
switch prioritizes each criteria for load balancing in the order listed in the 
option. The options are:
-Src/Dest MAC, VLAN, EType, incoming port—Source and destination 
MAC addresses, the VLAN membership, the Ethertype field, and the port 
on which the packet was received.
-Src/Dest IP and TCP/UDP Port Fields—Source and destination IP 
address and the TCP or UDP port number in the IP packet.
If the IP packet option is selected, non-IP packets received on the port are 
balanced using the Src and Dest MAC address.
•MTU—Specify the maximum transmission unit size in bytes. The default 
MTU is 1518 and the range is between 1518 and  bytes.
STEP  4Click Apply and then click Close. Your changes are saved to the Running 
Configuration. 
Configuring LACP
The switch uses the Link Aggregation Control Protocol (LACP) to automate the 
formation of dynamic LAGs. LACP-enabled ports send protocol data units 
(LACPDUs) to detect each other on a network and negotiate a LAG.
Use the LACP page to view and configure protocol operation.
To configure LACP settings on individual ports:
STEP 1Click Port Management > Link Aggregation > LACP in the navigation window.
The LACP Interface Table displays the following information for each port:
•LACP Mode—The administrative status of LACP mode (Enabled or 
Disabled)
The table displays the following information for the port when the port is the Actor 
(local) port:
•System Priority—A nonconfigurable system priority assigned to the 
switch. 
						

							Port Management
Link Aggregation
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•Admin Key—A number that determines the dynamic LAG(s) that the 
interface can join. All interfaces in a dynamic LAG must share the same 
admin key.
•Port Priority—A nonconfigurable priority assigned to the port.
•LACP Aggregation—The port mode with respect to link aggregation. This 
field is not configurable. Possible values are:
-Aggregate—The port is participating in link aggregation.
-Individual—The port is not participating in link aggregation and is 
functioning as an individual standalone port.
•LACP Passive—This field is always set to Active for all ports and is not 
configurable. It indicates that the port will continue to transmit LACPDUs 
after the LACPDU timeout has elapsed, regardless of the status of the link 
partner.
•LACP Timeout—The time after which an LACPDU is no longer valid (Long 
or Short).
The Table also displays the LACP Aggregation, LACP Passive, and LACP timeout 
values for the port when the port is the Partner (remote) port.
To edit the LACP settings:
STEP 1Select the port to configure and click Edit.
STEP  2Configure the following settings for the selected port:
•Mode—Check the box to enable LACP on the port.
•Actor Timeout—Information from the actor is no longer valid after the 
timeout period elapses. 
-Short—Short LACP timeout is 3 times the short periodic timer to 
transmit LACP packets. The default Short LACP timeout is 3 seconds.
-Long—Long LACP timeout is 3 times the long periodic timer to transmit 
LACP packets. The default Long LACP timeout is 90 seconds. 
•Partner Timeout—Information from the partner is no longer valid after the 
timeout period elapses. 
-Short—Short LACP timeout is 3 times the short periodic timer to 
transmit LACP packets. The default Short LACP timeout is 3 seconds. 
						

							Port Management
Configuring PoE
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-Long—Long LACP timeout is 3 times the long periodic timer to transmit 
LACP packets. The default Long LACP timeout is 90 seconds. 
STEP  3Click Apply and then click Close. Your changes are saved to the Running 
Configuration. 
Configuring PoE
On the SF200E-24P switch, ports 1–6 and 13–18 can operate as Power-over-
Ethernet (PoE) power-sourcing equipment (PSE). PSE ports can provide power to 
connected PoE Powered Devices (PD).
On switches with PSE ports, the following topics provide information on the 
configuration pages available in the Port Management > PoE menu:
•Configuring PoE Properties
•Configuring PoE Port Settings
NOTEThese configuration pages do not display on switches that do not support PSE 
functionality.
Configuring PoE Properties
You can use the Proper ties page to configure whether the switch generates trap 
messages under certain conditions and to view current power settings. 
To configure PoE properties:
STEP 1Click Port Management > PoE > Properties in the navigating window.
STEP  2Set the following parameters:
•Power Trap Threshold—Specify a percentage of total available system 
power. When the requested power on PoE ports exceeds the threshold, a 
trap is generated to the log. 
						

							Port Management
Configuring PoE
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•Power Management Mode—Select how the switch prioritizes the power 
that it provides to multiple ports:
-Static with Port Priority—Static with priority power management. This 
algorithm pre-allocates power based on the configured power limit and 
the priority of the port. 
-Dynamic with Port Priority—Dynamic with priority power 
management. This algorithm supplies power to devices as long as the 
consumption is within the configured limit and priority. There is no pre-
allocation of power.
In both modes, a port with a higher port priority is given preference when the 
switch supplies power to multiple ports. If two or more port priorities are 
equal, the port with the lower port number is given preference.
•Reset Mode—Select Enable to enable the switch initialize all PoE ports state 
machines.
STEP  3Click Apply. Your changes are saved to the Running Configuration.
NOTEThis page displays the following data for PoE power on the switch:
•Power: The current power status. If On, the switch is currently providing 
power through PoE to a connected device. If Off, the switch is not providing 
power through PoE to any connected devices.
•Maximum Available Power—The total power in watts that the switch is 
capable of making available to all PoE-capable ports. 
•Threshold Power—The cutoff power value above which no additional PDs 
are powered. This threshold is calculated based on the Power Trap 
Threshold setting.
•Allocated Power—The total power in watts that the switch is actually 
providing to PoE ports. 
						

							Port Management
Configuring PoE
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Configuring PoE Port Settings
You can use the Por t Settings page to view and configure settings for ports acting 
as PSEs.
To configure PoE settings for a port:
STEP 1Click Port Management > PoE > Port Settings in the navigation window.
The PoE Setting Table displays which ports are enabled for PoE operation, their 
priority, power allocation in milliwatts, and other settings for each port.
STEP  2Select the port to configure and click Edit.
STEP  3Configure the following settings:
•PoE—Check the Enable box to configure the port as a PSE.
•Power Priority Level—Select Critical, High, or Low to configure the port 
priority level, for the delivery of power to an attached device. 
The switch might not be able to supply power to all connected devices that 
request it. The port priority determines which ports supply power when 
adequate power capacity is not available for all enabled ports. For ports that 
have the same priority level, the lower-numbered port has higher priority. For 
a system delivering peak power to a certain number of devices, if a new 
device is attached on a high-priority port, power is shut down to a device on 
a low-priority port, and the new device is powered up. 
•Power Limit Type— Select one of the following methods to limit the power 
that the switch provides to a connected device.
-Dot3AF—The maximum power that can be delivered by the port is 
limited by the detected IEEE 802.3af class.
-User-defined—The maximum power that can be delivered by the port 
is specified by the user. If you select this option, specify a value in the 
Power Allocation field.
-LLDP-MED—The maximum power that can be delivered by the port is 
limited by the value in LLDP-MED TLVs received from a port device. The 
value specified by the device should be in the range of 3-16.2 watts. If it 
is not in this range, then the default value of 16.2 watts is used.
Note: If the selected Power Limit Type is LLDP-MED, then the priority 
setting from the remote device is not honored; instead the switch uses 
the Power Priority Level setting configured for the port. 
						

							Port Management
Configuring PoE
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-Dot3AF and LLDP-MED—The maximum power that can be delivered 
by the port is limited by the value in LLDP-MED TLVs received from a 
port device. The value specified by the device should be in the range of 
3-16.2 watts. If it is not in this range, then the maximum power is limited 
by the IEEE 802.3AF class.
-User-Defined and LLDP-MED—The maximum power that can be 
delivered by the port is limited by the value in LLDP-MED TLVs received 
from a port device. The value specified by the device should be in the 
range of 3-16.2 watts. If it is not in this range, then the maximum power is 
limited by the value that you specify in the Power Allocation field.
•Power Allocation—If you configured a user-defined option for Power Limit 
Type, enter the power in milliwatts to be allocated to the por t , between 3000 
to 16200 milliwatts.
•Detection Type—Select one of the following methods to detect PoE-
powered devices connected to the ports.
-802.3af 4point —Resistive signature devices detected with the first 
algorithm that correspond to the updated IEEE 802.3at-2009 PoE 
standard (also known as PoE+). It provides up to 51 W of power over a 
single cable by utilizing all four pairs in the Cat5 cable.
-802.3af 2point—Resistive signature devices detected with the first 
algorithm that correspond to the original IEEE 802.3af-2003 PoE standard 
that provides up to 15.4 W of DC power (minimum 44 V DC and 350 mA) 
to each device.
•Reset Mode—Select Enable to enable the switch initialize the ports PoE 
state machines.
The following statistics also appear:
•Power Consumption—Actual power consumption on the port.
•Overload Counter—Total number of power overload occurrences.
•Short Counter—Total number of power short condition (electrical shorts) on 
a port.
•Denied Counter—Number of times the powered device was denied power.
•Absent Counter—Number of times the power supply was stopped to the 
powered device because the powered device was no longer detected. 
						

							Port Management
Green Ethernet
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•Invalid Signature Counter—Number of times an invalid signature was 
received. Signatures are the means by which the powered device identifies 
itself to the PSE. A signature is generated during powered device detection, 
classification, or maintenance.
STEP  4Click Apply and then click Close. Your changes are saved to the Running 
Configuration.
Green Ethernet
The switch provides a Green Ethernet power saving feature on gigabit Ethernet 
copper ports called Energy Detect Mode. This feature helps reduce chip power 
by forcing a port PHY into a low-power mode when the signal from a copper link 
partner is not present. (PHY is an abbreviation for the physical layer of the OSI 
model.)
When the Energy Detect is enabled, the switch automatically enters the low-
power mode when energy on the line is lost, and it resumes normal operation 
when energy is detected. When the port PHY is in low-power mode, the PHY 
wakes up after a certain period of time, and sends link pulses to monitor for energy 
from the link partner. If energy is detected while the port is in wake-up mode, the 
switch returns the port to normal operation. When the wake-up period expires, the 
port returns to low-power mode. 
Energy Detect works whether the port has autonegotiation enabled or disabled, 
and can be enabled or disabled by the administrator. The Energy Detect Mode 
properties are configurable per-port.
Se e the following topic s for more information on the configuration pages available 
in the Port Management > Green Ethernet menu:
•Configuring Green Ethernet Properties
•Configuring Green Ethernet Port Settings
Configuring Green Ethernet Properties
You can use the Green Ethernet Proper ties page to enable Green Ethernet 
functionality globally. The global settings are applied to all ports. 
NOTEYou can override the global settings by configuring these features on individual 
ports (see Configuring Green Ethernet Port Settings); however, changes you 
subsequently make to the global settings override any custom port configuration.