Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 105

Auth-Fail VLAN id: Auth-Fail Max-Attempts: Critical VLAN: Critical VLAN id: Mac-Auth-Bypass: Mac-Auth-Bypass Only: Static-MAB: Static-MAB Profile: Tx Period: Quiet Period: ReAuth Max: Supplicant Timeout: Server Timeout: Re-Auth Interval: Max-EAP-Req: Host Mode: Auth PAE State: Backend State: NONE NONE Disable NONE Enable Disable Disable NONE 30 seconds 60 seconds 2 30 seconds 30 seconds 3600 seconds 2 SINGLE_HOST Authenticated Idle Dynamic CoS with 802.1X Class of Service (CoS) is a method of traffic management that groups similar types of traffic so that they are serviced differently. One way of classifying traffic is 802.1p, which uses the 3-bit Priority field in the VLAN tag to mark frames (other classification methods include ToS, ACL, and DSCP). Once traffic is classified, you can use Quality of Service (QoS) traffic management to control the level of service for a class in terms of bandwidth and delivery time. For incoming traffic, the Dell Networking OS allows you to set a static priority value on a per-port basis or dynamically set a priority on a per-port basis by leveraging 802.1X. NOTE: When a priority is statically configured using the dynamic dot1p command and dynamically configured using dynamic CoS with 802.1X, the dynamic configuration takes precedence. You can use dynamic CoS with 802.1X is when the traffic from a server should be classified based on the application that it is running. A static dot1p priority configuration applied from the switch is not sufficient in this case, as the server application might change. You would instead need to push the CoS configuration to the switches based on the application the server is running. Dynamic CoS uses RADIUS attribute 59, called User-Priority-Table, to specify the priority value for incoming frames. Attribute 59 has an 8-octet field that maps the incoming dot1p values to new values; it is essentially a dot1p re-mapping table. The position of each octet corresponds to a priority value: the first octet maps to incoming priority 0, the second octet maps to incoming priority 1, etc. The value in each octet represents the corresponding new priority. To use dynamic CoS with 802.1X authentication, no configuration command is required. You must only configure the supplicant records on the RADIUS server, including VLAN assignment and CoS priority re-mapping table. VLAN and priority values are automatically applied to incoming packets. The RADIUS server finds the appropriate record based on the supplicant's credentials and sends the priority re-mapping table to the Dell Networking system by including Attribute 59 in the AUTHACCEPT packet. The following conditions apply to the use of dynamic CoS with 802.1X authentication on the switch: • In accordance with port-based QoS, incoming dot1p values can be mapped to only four priority values: 0, 2, 4, and 6. If the RADIUS server returns any other dot1p value (1, 3, 5, or 7), the value is not used and frames are forwarded on egress queue 0 without changing the incoming dot1p value. The example shows how dynamic CoS remaps (or does not remap) the dot1p priority in 802.1X-authenticated traffic and how the frames are forwarded: Incoming Frame Tagged dot1p 0 1 2 3 4 RADIUS-based CoS Remap Table 7 5 4 6 3 Outgoing Frame Egress Queue Tagged dot1p 0 0 1 0 4 2 6 3 4 0 802.1X 105