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DES-3500 Layer 2 Fast Ethernet Switch CLI Reference Manual
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further specify in the new rule to deny access to a range of IP addresses through an individual port: Here, we want to filter any
packets that have an IP source address between 10.42.73.0 and 10.42.73.255, and specify the port that will not be allowed:
config access_profile profile_id 1 add access_id 1 ip source_ip 10.42.73.1 port 7 deny
We use the profile_id 1 which was specified when the access profile was created. The add parameter instructs the Switch to add
the criteria that follows to the list of rules that are associated with access profile 1. For each rule entered into the access profile,
users can assign an access_id that identifies the rule within the list of rules. The access_id is an index number only and does not
effect priority within the profile_id. This access_id may be used later if users want to remove the individual rule from the profile.
The ip parameter instructs the Switch that this new rule will be applied to the IP addresses contained within each frame’s header.
source_ip tells the Switch that this rule will apply to the source IP addresses in each frame’s header. The IP address 10.42.73.1
will be combined with the source_ip_mask 255.255.255.0 to give the IP address 10.42.73.0 for any source IP address between
10.42.73.0 to 10.42.73.255. Finally the restricted port - port number 7 - is specified.
Due to a chipset limitation, the Switch supports a maximum of 9 access profiles. The rules used to define the access profiles are
limited to a total of 800 rules for the Switch.
There is an additional limitation on how the rules are distributed among the Fast Ethernet and Gigabit Ethernet ports. This
limitation is described as follows: Fast Ethernet ports are limited to 200 rules for each of the three sequential groups of eight ports.
That is, 200 ACL profile rules may be configured for ports 1 to 8. Likewise, 200 rules may be configured for ports 9 to 16, and
another 200 rules for ports 17 to 24. Up to 100 rules may be configured for each Gigabit Ethernet port. The table below provides a
summary of the maximum ACL profile rule limits.
DES-3526/DES-3526DC DES-3550
Port Numbers
Maximum ACL Profile Rules per
Port Group
1 - 8 200
9 - 16 200
17 - 24 200
25 - 32 200
33 - 40 200
41 - 48 200
49 (Gigabit) 100
50 (Gigabit) 100
Total Rules 800
It is important to keep this in mind when setting up VLANs as well. Access rules applied to a VLAN require that a rule be created
for each port in the VLAN. For example, let’s say VLAN10 contains ports 2, 11 and 12. If users create an access profile
specifically for VLAN10, users must create a separate rule for each port. Now take into account the rule limit. The rule limit
applies to both port groups 1-8 and 9-16 since VLAN10 spans these groups. One less rule is available for port group 1-8. Two less
rules are available for port group 9-16. In addition, a total of three rules apply to the 800 rule Switch limit.
In the example used above - config access_profile profile_id 1 add access_id 1 ip source_ip 10.42.73.1 port 7 deny – a single
access rule was created. This rule will subtract one rule available for the port group 1 – 8, as well as one rule from the total
available rules.
create access_profile
Purpose Used to create an access profile on the Switch and to define which parts of each incoming
frame’s header the Switch will examine. Masks can be entered that will be combined with
the values the Switch finds in the specified frame header fields. Specific values for the rules
are entered using the config access_profile command, below.
Syntax
create access_profile [ethernet {vlan | source_mac <macmask> |
destination_mac <macmask> | 802.1p | ethernet_type} | ip {vlan |
source_ip_mask <netmask> | destination_ip_mask <netmask> | dscp | [icmp {type |
code} | igmp {type} | tcp {src_port_mask <hex 0x0-0xffff> | dst_port_mask <hex 0x0-
0xffff> | flag_mask [all | {urg | ack | psh | rst | syn | fin}]} | udp {src_port_mask
Port Numbers
Maximum ACL Profile Rules per
Port Group
1 - 8 200
9 – 16 200
17 - 24 200
25 (Gigabit) 100
26 (Gigabit) 100
Total Rules 800