3com S7906E Manuel De Montage

 

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Enter system view 

— 

Enter 
Ethernet 
interface view 

interface interface-type 
interface-number 

Enter Ethernet 
interface view 
or port group 
view 

Enter port 
group view 

port-group manual 
port-group-name 

Required 

Use either command. 

Set the encapsulation format 
for LLDPDUs to SNAP 

lldp encapsulation snap 

Required 

Ethernet II encapsulation 
format applies by default. 

To restore the default, use 
the undo lldp 
encapsulation command.  

 

Both the LLDPDU transmit interval and delay must be less than the TTL to ensure that the LLDP 

neighbors can receive LLDP frames to update information about the device you are configuring before 

it is aged out. 

 

 

For detailed information about voice VLAN, refer to VLAN Configuration in the Access Volume.  

 

You need to enable CDP compatibility for your device to work with Cisco IP phones. 

As your LLDP-enabled device cannot recognize CDP packets, it does not respond to the requests of 

Cisco IP phones for the voice VLAN ID configured on the device. This can cause a requesting Cisco IP 

phone to send voice traffic without any tag to your device, disabling your device to differentiate the voice 

traffic from other types of traffic. 

By configuring CDP compatibility, you can enable LLDP on your device to receive and recognize CDP 

packets from Cisco IP phones and respond with CDP packets carrying the voice VLAN configuration 

TLV for the IP phones to configure the voice VLAN automatically. Thus, the voice traffic is confined in 

the configured voice VLAN to be differentiated from other types of traffic.  

Before configuring CDP compatibility, make sure that: 

z 

LLDP is enabled globally.  

z 

LLDP is enabled on the port connected to an IP phone and is configured to operate in TxRx mode 

on the port.