Cisco Catalyst 3750-X Command Reference

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Catalyst 3750-X and 3560-X Switch Command Reference
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Chapter 2 Catalyst 3750-X and 3560-X Switch Cisco IOS Commands
deny (IPv6 access-list configuration)
Usage Guidelines The deny (IPv6 access-list configuration mode) command is similar to the deny (IPv4 access-list
configuration mode) command, but it is IPv6-specific.
Use the deny (IPv6) command after the ipv6 access-list command to enter IPv6 access list configuration
mode and to define the conditions under which a packet passes the access list.
Specifying IPv6 for the protocol argument matches against the IPv6 header of the packet.
By default, the first statement in an access list is number 10, and the subsequent statements are numbered
in increments of 10.
You can add permit, deny, or remark statements to an existing access list without re-entering the entire
list. To add a new statement anywhere other than at the end of the list, create a new statement with an
appropriate entry number between two existing entry numbers to show where it belongs.
Note Every IPv6 ACL has implicit permit icmp any any nd-na, permit icmp any any nd-ns, and deny ipv6
any any statements as its last match conditions. The two permit conditions allow ICMPv6 neighbor
discovery. To disallow ICMPv6 neighbor discovery and to deny icmp any any nd-na or icmp any any
nd-ns, there must be an explicit deny entry in the ACL. For the three implicit statements to take effect,
an IPv6 ACL must contain at least one entry.
The IPv6 neighbor discovery process uses the IPv6 network layer service. Therefore, by default, IPv6
ACLs implicitly allow IPv6 neighbor discovery packets to be sent and received on an interface. In IPv4,
the Address Resolution Protocol (ARP), which is equivalent to the IPv6 neighbor discovery process, uses
a separate data-link layer protocol. Therefore, by default, IPv4 ACLs implicitly allow ARP packets to
be sent and received on an interface.
Both the source-ipv6-prefix/prefix-length and destination-ipv6-prefix/prefix-length arguments are used
for traffic filtering. (The source prefix filters traffic based upon the traffic source; the destination prefix
filters traffic based upon the traffic destination.)
The switch supports IPv6 address matching for a full range of prefix-lengths.
The fragments keyword is an option only if the protocol is ipv6 and the operator [port-number]
arguments are not specified.
This is a list of ICMP message names:
beyond-scope destination-unreachable
echo-reply echo-request
header hop-limit
mld-query mld-reduction
mld-report nd-na
nd-ns next-header
no-admin no-route
packet-too-big parameter-option
parameter-problem port-unreachable
reassembly-timeout renum-command
renum-result renum-seq-number
router-advertisement router-renumbering

Cisco Catalyst 3750-X Specifications

General

Switching Capacity	160 Gbps
Stacking Bandwidth	64 Gbps
Max Stacking Units	9
Layer Support	Layer 2 and Layer 3
Form Factor	Rack-mountable
DRAM	256 MB
Flash Memory	64 MB
Model	Cisco Catalyst 3750-X Series
Ports	24 or 48 10/100/1000 Ethernet ports
Uplink Interfaces	4 SFP or 2 SFP+
Features	StackWise Plus, EnergyWise
Image	IP Base or IP Services
Operating Temperature	0 to 40°C
Operating Humidity	10 to 85% noncondensing