User manual

C HAPTER 4 | Configuring the Switch
Configuring Security
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N OTE : For trouble-shooting VLAN assignments, use the Monitor > VLANs >
VLAN Membership and VLAN Port pages. These pages show which modules
have (temporarily) overridden the current Port VLAN configuration.
Guest VLAN Operation
When a Guest VLAN enabled port's link comes up, the switch starts
transmitting EAPOL Request Identity frames. If the number of
transmissions of such frames exceeds Max. Reauth. Count and no
EAPOL frames have been received in the meanwhile, the switch
considers entering the Guest VLAN. The interval between transmission
of EAPOL Request Identity frames is configured with EAPOL Timeout. If
Allow Guest VLAN if EAPOL Seen is enabled, the port will now be placed
in the Guest VLAN. If disabled, the switch will first check its history to
see if an EAPOL frame has previously been received on the port (this
history is cleared if the port link goes down or the port's Admin State is
changed), and if not, the port will be placed in the Guest VLAN.
Otherwise it will not move to the Guest VLAN, but continue transmitting
EAPOL Request Identity frames at the rate given by EAPOL Timeout.
Once in the Guest VLAN, the port is considered authenticated, and all
attached clients on the port are allowed access on this VLAN. The
switch will not transmit an EAPOL Success frame after entering the
Guest VLAN.
While in the Guest VLAN, the switch monitors the link for EAPOL
frames, and if one such frame is received, the switch immediately takes
the port out of the Guest VLAN and starts authenticating the supplicant
according to the port mode. If an EAPOL frame is received, the port will
never be able to go back into the Guest VLAN if the “Allow Guest VLAN
if EAPOL Seen” is disabled.
◆ Guest VLAN ID - This is the value that a port's Port VLAN ID is set to if
a port is moved into the Guest VLAN. It is only changeable if the Guest
VLAN option is globally enabled. (Range: 1-4095)
◆ Max. Reauth. Count - The number of times that the switch transmits
an EAPOL Request Identity frame without receiving a response before
adding a port to the Guest VLAN. The value can only be changed if the
Guest VLAN option is globally enabled. (Range: 1-255)
◆ Allow Guest VLAN if EAPOL Seen - The switch remembers if an
EAPOL frame has been received on the port for the lifetime of the port.
Once the switch considers whether to enter the Guest VLAN, it will first
check if this option is enabled or disabled. If disabled (the default), the
switch will only enter the Guest VLAN if an EAPOL frame has not been
received on the port for the lifetime of the port. If enabled, the switch
will consider entering the Guest VLAN even if an EAPOL frame has been
received on the port for the lifetime of the port. The value can only be
changed if the Guest VLAN option is globally enabled.
Port Configuration
◆ Port – Port identifier.