DHCP snooping
List of terms:
MAC Address: The MAC address of the snooped DHCP client.
IP Address: The IP address that has been allocated to the snooped DHCP client.
Expires: The time, in seconds, until the DHCP client entry will expire.
VLAN: The VLAN to which the snooped DHCP client is connected.
Port: The port to which the snooped DHCP client is connected.
ID: The unique ID for the entry in the DHCP snooping database. This ID is dynamically allocated to all clients. (The same ID can be seen in show dhcpsnooping filter.)
Database Listeners: These are switch features (or modules) that have registered to listen to the Binding Database. Database listeners are informed when an entry is added or deleted from the database. In this case the Classifier module will be informed so the dynamic classifiers can be updated.
Source: How the DHCP binding was entered into the database:
zUser = static
zFile = read from bindings. dsn (usually at boot time)
zDynamic = it was snooped
To see port details, use the commands show dhcpsnooping port and show dhcpsnooping count.
Manager > show dhcpsnooping port=16 | |
DHCP Snooping Port Information: | |
Port | 16 |
Trusted | No |
Full Leases/Max Leases ... 1/1 | |
Manager > show dhcpsnooping count | |
DHCP Snooping Counters |
|
DHCP Snooping |
|
InPackets | 1751 |
InBootpRequests | 908 |
InBootpReplies | 843 |
InDiscards | 0 |
ARP Security |
|
InPackets | 0 |
InDiscards | 0 |
NoLease | 0 |
Invalid | 0 |
Page 5 AlliedWare™ OS How To Note: DHCP Snooping on
