Installation and Getting Started Guide
The <dest-mac> <mask> | any parameter specifies the destination MAC address. The syntax rules are the same
as those for the <src-mac> <mask> | any parameter.
Use the etype | llc | snap argument if you want to filter on information beyond the source and destination address.
The MAC filter allows for you to filter on the following encapsulation types:
etype (Ethertype) – a two byte field indicating the protocol type of the frame. This can range from 0x0600 to
llc (IEEE 802.3 LLC1 SSAP and DSAP) – a two byte sequence providing similar function as the EtherType
but for an IEEE 802.3 frame.
snap (IEEE 802.3 LLC1 SNAP) – a specific LLC1 type packet.
To determine which type of frame is used on your network, use a protocol analyzer. If byte 12 of an Ethernet
packet is equal to or greater than 0600 (hex), it is an Ethernet framed packet. Any number below this indicates an
IEEE 802.3 frame (byte 12 will now indicate the length of the data field). Some well-known Ethernet types are
0800 (TCP/IP), 0600 (XNS), and 8137 (Novell Netware). Refer to RFC 1042 for a complete listing of EtherTypes.
For IEEE 802.3 frame, you can further distinguish the SSAP and DSAP of LLC header. Some well-known SAPs
include: FE (OSI), F0 (NetBIOS), 42 (Spanning Tree BPDU), and AA (SNAP). Usually the DSAP and SSAP are
NOTE: You must type in both bytes, otherwise the software will fill the field, left justified with a 00. Refer to RFC
1042 for a complete listing of SAP numbers.
SNAP is defined as an IEEE 802.3 frame with the SSAP, DSAP, and control field set to AA, AA, and 03.
Immediately following these is a five-byte SNAP header. The first three bytes in this header are not used by the
MAC filters. However, the next two bytes usually are set to the EtherType, so you can define the EtherType inside
the SNAP header that you want to filter on.
The eq | gt | lt | neq argument specifies the possible operator: eq (equal), gt (greater than), lt (less than) and neq
The <frame-type> argument is a hexadecimal number for the frame type. For example, the hex number for ARP
Syntax: mac filter log-enable
Enables logging for filtered packets.
Syntax: mac-filter-group <filter-list>
Applies MAC filters to a port.
NOTE: Remember that the filters must be applied as a group. For example, if you want to apply four filters to an
interface, they must all appear on the same command line.
USING THE WEB MANAGEMENT INTERFACE
To define a MAC filter:
Log on to the device using a valid user name and password for read-write access. The System configuration
panel is displayed.
Click on the plus sign next to Configure in the tree view to display the configuration options.
Click on the plus sign next to System in the tree view to display the system configuration options.
Select the MAC Filter link.
If the device does not have any MAC filters configured, the MAC Filter configuration panel is displayed,
as shown in the following example.
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