Chapter 4: Web management
NS3550-8T-2S Industrial Managed Switch User Manual
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The page includes the following fields:
Object
Description
MAC Address &
VLAN ID
The MAC address and VLAN ID that is seen on this port. If no MAC
addresses are learned, a single row stating "No MAC addresses attached" is
displayed.
State
Indicates whether the corresponding MAC address is blocked or forwarding.
In the blocked state, it will not be allowed to transmit or receive traffic.
Time of Addition
Shows the date and time when this MAC address was first seen on the port.
Age/Hold
If at least one user module has decided to block this MAC address, it will
stay in the blocked state until the hold time (measured in seconds) expires.
If all user modules have decided to allow this MAC address to forward, and
aging is enabled, the Port Security module will periodically check that this
MAC address still forwards traffic.
If the age period (measured in seconds) expires and no frames have been
seen, the MAC address will be removed from the MAC table. Otherwise a
new age period will begin.
If aging is disabled or a user module has decided to hold the MAC address
indefinitely, a dash (-) will be shown.
Buttons
• Click
Refresh
to refresh the page immediately.
• Click
Auto-refresh
to refresh the page automatically. Automatic refresh occurs
every three seconds.
DHCP snooping
DHCP snooping is used to block intruders on the untrusted ports of DUT when it tries to
intervene by injecting a bogus DHCP reply packet to a legitimate conversation between
the DHCP client and server.