Dell S4048-ON, Configuration Manual

Page: 683 / 1039

The following example matches IPv6 traffic with a DSCP value of 40.
Dell(conf)# class-map match-all test
Dell(conf-class-map)# match ipv6 dscp 40
The following example matches IPv4 and IPv6 traffic with a precedence value of 3.
Dell(conf)# class-map match-any test1
Dell(conf-class-map)#match ip-any precedence 3
Creating a Layer 2 Class Map
All class maps are Layer 3 by default; however, you can create a Layer 2 class map by specifying the
layer2
option with the
class-map
command.
A Layer 2 class map differentiates traffic according to 802.1p value and/or VLAN and/or characteristics defined in a MAC ACL..
Use Step 1 or Step 2 to start creating a Layer 2 class map.
1. Create a match-any class map.
CONFIGURATION mode
class-map match-any
2. Create a match-all class map.
CONFIGURATION mode
class-map match-all
3. Specify your match criteria.
CLASS MAP mode
match mac
After you create a class-map, Dell Networking OS places you in CLASS MAP mode.
Match-any class maps allow up to five access-lists. Match-all class-maps allow only one. You can match against only one VLAN
ID.
4. Link the class-map to a queue.
POLICY MAP mode
service-queue
Determining the Order in Which ACLs are Used to Classify Traffic
When you link class-maps to queues using the
service-queue
command, Dell Networking OS matches the class-maps according
to queue priority (queue numbers closer to 0 have lower priorities).
For example, as described in the previous example, class-map
cmap2 is matched against ingress packets before cmap1 .
ACLs acl1 and acl2 have overlapping rules because the address range 20.1.1.0/24 is within 20.0.0.0/8. Therefore (without the
keyword
order
), packets within the range 20.1.1.0/24 match positive against cmap1 and are buffered in queue 7, though you
intended for these packets to match positive against cmap2 and be buffered in queue 4.
In cases such as these, where class-maps with overlapping ACL rules are applied to different queues, use the keyword order . Dell
Networking OS writes to the CAM ACL rules with lower order numbers (order numbers closer to 0) before rules with higher order
numbers so that packets are matched as you intended.
• Specify the order in which you want to apply ACL rules using the keyword order .
order
The order can range from 0 to 254.
By default, all ACL rules have an order of 255 .
Quality of Service (QoS)
683