3com 5500-SI Manual De Usuario

Access Management Configuration 299

Perform the following procedure if a user cannot apply for an IP address dynamically:

1 Use the 

 

 command to check if the IP address of the 

corresponding DHCP Server has been configured.

2 Use the 

 and 

 commands to 

check if the VLAN and the corresponding interface IP address have been configured.

3 Ping the configured DHCP Server to ensure that the link is connected.

4 Ping the IP address of the VLAN interface of the Switch to which the DHCP user is

 

connected from the DHCP Server to make sure that the DHCP Server can correctly 
find the route of the network segment the user is on. If the ping execution fails, check 
if the default gateway of the DHCP Server has been configured as the address of the 
VLAN interface that it locates on. 

If there is no problem found in the last two steps, use the 

 command to view which packet has been received. If you only see the 

Discover packet and there is no response packet, the DHCP Server has not sent the 
message to the Switch. In this case, check if the DHCP Server has been configured 
properly. If the numbers of request and response packets are normal, enable the 

 in User View and then use the 

 

command to output the debugging information to the console. In this way, you can 
view the detailed information of all DHCP packets on the console as they apply for 
the IP address, and so locate the problem.

This section contains Access Management configuration information.

In networking, the ports in a Switch which access different users belong to the same 
VLAN and they cannot communicate with each other, for the purposes of security, 
simplicity, and saving VLAN resources. Different ports have different IP addresses and 
only the users with an IP address which is allowed to pass the port can access the 
external network through the port. You can achieve this configuration using the 
functions binding Switch port with IP address and port layer-2 isolating. 

Access management configuration includes:

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■

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You can use the following command to enable the access management function. 
Only after the access management function is enabled will the access management 
features (IP and port binding and Layer 2 port isolation) take effect.

Perform the following configuration in System View.

Table 293   Enabling/Disabling the Access Management Function

Enable access management function