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PowerConnect B-Series FCX Configuration Guide
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DHCP snooping
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1. Enable DHCP snooping on a VLAN.Refer to
“Enabling DHCP snooping on a VLAN”
on
page 1352.
2. For ports that are connected to a DHCP server, change their trust setting to trusted.Refer to
“Enabling trust on a port”
on page 1352.
The following shows the default settings of DHCP snooping.
Enabling DHCP snooping on a VLAN
When DHCP snooping is enabled on a VLAN, DHCP packets are inspected.
DHCP snooping is disabled by default. This feature must be enabled on the client and the DHCP
server VLANs. To enable DHCP snooping, enter the following global command for these VLANs.
PowerConnect(config)#ip dhcp snooping vlan 2
The command enables DHCP snooping on VLAN 2.
Syntax: [no] ip dhcp snooping vlan
<vlan-number>
The
<vlan-number>
variable specifies the ID of a configured client or DHCP server VLAN.
Enabling trust on a port
The default trust setting for a port is untrusted. To enable trust on a port connected to a DHCP
server, enter commands such as the following.
PowerConnect(config)#interface ethernet 1/1
PowerConnect(config-if-e10000-1/1)#dhcp snooping trust
Port 1/1 is connected to a DHCP server. The commands change the CLI to the interface
configuration level of port 1/1 and set the trust setting of port 1/1 to trusted.
Syntax: [no] dhcp snooping trust
Disabling the learning of DHCP clients on a port
You can disable DHCP client learning on an individual port. To do so, enter commands such as the
following.
PowerConnect(config)#interface ethernet 1/1
PowerConnect(config-if-e10000-1/1)#dhcp snooping client-learning disable
Syntax: [no] dhcp snooping client-learning disable
Use the no form of the command to re-enable DHCP client learning on a port once it has been
disabled.
Clearing the DHCP binding database
You can clear the DHCP binding database using the CLI command clear DHCP. You can remove all
entries in the database, or remove entries for a specific IP address only.
Feature
Default
DHCP snooping
Disabled
Trust setting for ports
Untrusted
Содержание PowerConnect B-FCXs
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Страница 228: ...186 PowerConnect B Series FCX Configuration Guide 53 1002266 01 PowerConnect B Series FCX hitless stacking 5 ...
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Страница 346: ...304 PowerConnect B Series FCX Configuration Guide 53 1002266 01 802 1s Multiple Spanning Tree Protocol 8 ...
Страница 374: ...332 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Jumbo frame support 9 ...
Страница 424: ...382 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Virtual Switch Redundancy Protocol VSRP 10 ...
Страница 568: ...526 PowerConnect B Series FCX Configuration Guide 53 1002266 01 CLI examples 14 ...
Страница 588: ...546 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Sample application 15 ...
Страница 674: ...632 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Enabling or disabling layer 2 switching 19 ...
Страница 684: ...642 PowerConnect B Series FCX Configuration Guide 53 1002266 01 VLAN based mirroring 20 ...
Страница 724: ...682 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Reading CDP packets 23 ...
Страница 768: ...726 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Clearing cached LLDP neighbor information 24 ...
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Страница 948: ...906 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Configuring MLD snooping 27 ...
Страница 962: ...920 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Displaying CPU utilization statistics 28 ...
Страница 1022: ...980 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Displaying OSPF information 29 ...
Страница 1142: ...1100 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Clearing diagnostic buffers 30 ...
Страница 1258: ...1216 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Using Secure copy with SSH2 33 ...
Страница 1314: ...1272 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Displaying port security information 35 ...
Страница 1348: ...1306 PowerConnect B Series FCX Configuration Guide 53 1002266 01 Example configurations 36 ...
Страница 1406: ...1364 PowerConnect B Series FCX Configuration Guide 53 1002266 01 IP source guard 39 ...
Страница 1422: ...1380 PowerConnect B Series FCX Configuration Guide 53 1002266 01 SNMP v3 Configuration examples 40 ...