Cisco CATALYST 2960 - Understanding DHCP-Based Autoconfiguration; DHCP provides configuration information to Internet hosts and internetworking devices. This protocol consists of two components: one for delivering configuration parameters from a DHCP server to a device and a mechanism for allocating network addresses to devices. DHCP is built on a client-server model, in which designated DHCP servers allocate network addresses and deliver configuration parameters to dynamically configured devices. The switch can act as both a DHCP client and a DHCP server.; During DHCP-based autoconfiguration, your switch (DHCP client) is automatically configured at startup with IP address information and a configuration file.; However, you need to configure the DHCP server for various lease options associated with IP addresses. If you are using DHCP to relay the configuration file location on the network, you might also need to configure a Trivial File Transfer Protocol (TFTP) server and a Domain Name System (DNS) server.

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Catalyst 2960 Switch Command Reference
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Chapter 2 Catalyst 2960 Switch Cisco IOS Commands
deny (MAC access-list configuration)
deny (MAC access-list configuration)
Use the deny MAC access-list configuration command to prevent non-IP traffic from being forwarded
if the conditions are matched. Use the no form of this command to remove a deny condition from the
named MAC access list.
{deny | permit} {any | host src-MAC-addr | src-MAC-addr mask} {any | host dst-MAC-addr |
dst-MAC-addr mask} [type mask | aarp | amber | cos cos | dec-spanning | decnet-iv |
diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | lsap lsap mask |mop-console |
mop-dump | msdos | mumps | netbios | vines-echo | vines-ip | xns-idp]
no {deny | permit} {any | host src-MAC-addr | src-MAC-addr mask} {
any | host dst-MAC-addr |
dst-MAC-addr mask} [type mask | aarp | amber | cos cos | dec-spanning | decnet-iv |
diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | lsap lsap mask | mop-console |
mop-dump | msdos | mumps | netbios | vines-echo | vines-ip | xns-idp]
Syntax Description any Keyword to specify to deny any source or destination MAC address.
host src MAC-addr |
src-MAC-addr mask
Define a host MAC address and optional subnet mask. If the source
address for a packet matches the defined address, non-IP traffic from that
address is denied.
host dst-MAC-addr |
dst-MAC-addr mask
Define a destination MAC address and optional subnet mask. If the
destination address for a packet matches the defined address, non-IP
traffic to that address is denied.
type mask (Optional) Use the Ethertype number of a packet with Ethernet II or
SNAP encapsulation to identify the protocol of the packet.
The type is 0 to 65535, specified in hexadecimal.
The mask is a mask of don’t care bits applied to the Ethertype before
testing for a match.
aarp (Optional) Select Ethertype AppleTalk Address Resolution Protocol that
maps a data-link address to a network address.
amber (Optional) Select EtherType DEC-Amber.
cos
cos (Optional) Select a class of service (CoS) number from 0 to 7 to set
priority. Filtering on CoS can be performed only in hardware. A warning
message reminds the user if the cos option is configured.
dec-spanning (Optional) Select EtherType Digital Equipment Corporation (DEC)
spanning tree.
decnet-iv (Optional) Select EtherType DECnet Phase IV protocol.
diagnostic (Optional) Select EtherType DEC-Diagnostic.
dsm (Optional) Select EtherType DEC-DSM.
etype-6000 (Optional) Select EtherType 0x6000.
etype-8042 (Optional) Select EtherType 0x8042.
lat (Optional) Select EtherType DEC-LAT.
lavc-sca (Optional) Select EtherType DEC-LAVC-SCA.