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05-QCN configuration | 183.56 KB |
Contents
Restrictions and guidelines: QCN configuration
Prerequisites for QCN configuration
Configuring global CND settings
Configuring CND settings for an interface
Applying a congestion detection profile
Display and maintenance commands for QCN
Example: Configuring basic QCN
Example: Configuring MultiCND QCN
Configuring QCN
About QCN
Quantized Congestion Notification (QCN) is an end-to-end congestion notification mechanism that can reduce packet loss and delay in Layer 2 networks by actively sending reverse notifications. QCN is primarily used in data center networks.
How QCN works
As shown in Figure 1, in a QCN network, all reaction points (RPs) and congestion points (CPs) must support QCN. RPs and CPs configured with a congestion notification priority value (CNPV) form a congestion notification domain (CND).
Figure 1 shows how QCN works.
· Ethernet frames sent by an RP contain different congestion controlled flows (CCFs). The 802.1p value in an Ethernet frame uniquely identifies a CCF. The CP maps different CCFs to different queues according to the dot1p-lp mapping table.
· The CP enables QCN for a queue according to the 802.1p priority ((CNPV) in Ethernet frames and samples frames from the QCN-enabled queue. The CP sends congestion notification messages (CNMs) to the RP when congestion occurs.
· The RP reduces the transmission rate for packets with the 802.1p value when receiving CNMs. The RP also periodically probes the bandwidth and increases the transmission rate if it fails to receive CNMs for a specific period of time.
QCN messages
Data flow format
As shown in Figure 2, the CN tag contains the following fields:
· EtherType—Indicates the Ethernet type of the data packet, 2 bytes in length and assigned a value of 0x22E9.
· RPID—Locally assigned and 2 bytes in length. When receiving a CNM, the RP uses this field to identify the CCF that causes congestion and then rate limits that CCF.
When only one CCF exists, the RP may not add a CN tag to packets. In this case, the triggered CNM carries a CN tag with the RPID as 0.
A CN tag is confined within its CND. When a packet leaves a CND, the CN tag is stripped off.
CNM format
When a CP detects the congestion state by sampling frames, it sends CNMs to the RPs.
The CP constructs a CNM as follows:
· Uses the source MAC address of the sampled frame as the destination MAC address.
· Uses the MAC address of the CP as the source MAC address.
· Copies the VLAN tag and CN tag of the sampled frame.
· Places the data as shown in Figure 3.
¡ PDU EtherType—2 bytes in length. It indicates the Ethernet type of the PDU and has a value of 0x22E7.
¡ CNM PDU—24 to 88 bytes of payload of the PDU.
As shown in Figure 4, a payload contains the following fields:
Field |
Length |
Description |
Version |
4 bits |
Its value is fixed at 0. |
ReserverV |
6 bits |
Its value is fixed at 0. |
Quantized Feedback |
6 bits |
Quantized value indicating the extent of congestion. |
CPID |
8 bytes |
Identifies the CP where congestion occurs. |
cnmQoffset |
2 bytes |
Indicates the difference between instantaneous queue size at the sampling point and desired queue length. |
cnmQdelta |
2 bytes |
Indicates the difference between instantaneous queue sizes at the current sampling point and at the previous sampling point. |
Encapsulated priority |
2 bytes |
Priority of the sampled frame that triggered the CNM. |
Encapsulated destination MAC address |
6 bytes |
Destination MAC address of the sampled frame that triggered the CNM. |
Encapsulated MSDU length |
2 bytes |
Number of bytes in the Encapsulated MSDU field of the sampled frame that triggered the CNM. |
Encapsulated MSDU |
0 to 64 bytes |
Initial bytes of the Encapsulated MSDU field of the sampled frame that triggered the CNM. |
QCN algorithm
The QCN algorithm includes the CP algorithm and the RP algorithm.
CP algorithm
The CP measures the queue size by periodically sampling frames and computes the congestion state based on the sampling result.
As shown in Figure 5, the CP algorithm includes the following parameters:
· Q—Indicates the instantaneous queue size at the sampling point.
· Qeq—Indicates the desired queue size.
· Qold—Indicates the queue size at the previous sampling point.
· Fb—Indicates in a CNM the extent of congestion in the form of a quantized value.
The following formulas apply:
· cnmQoffset = Q – Qeq
· cnmQdelta = Q – Qold
· Fb = – (cnmQoffset + wcnmQdelta)
where w is a constant to control the weight of cnmQdelta in determining the value of Fb.
The CP determines whether to generate CNMs based on the Fb value.
· When Fb ≥ 0, no congestion occurs, and the CP does not generate a CNM.
· When Fb < 0, congestion occurs, and the CP generates an CNM containing the QntzFb. QntzFb is the quantized value of |Fb| and is calculated according to the following rules:
¡ If Fb < – Qeq x (2 x w + 1), QntzFb takes the maximum value of 63.
¡ Otherwise, QntzFb = – Fb x 63/(Qeq x (2 x w + 1)).
RP algorithm
An RP decreases its transmission rate based on the value of |Fb| in the received CNM. The greater the Fb value, the lower the RP reduces its transmission rate. After the RP reduces its transmission rate, the RP gradually increases the transmission rate to the original level.
CND
About this task
CNDs are identified based on CNPVs, which correspond to 802.1p values in Ethernet frames. Devices enabled with QCN for a CNPV are assigned to the corresponding CND. After receiving a packet with a CNPV, the device assigns the packet to the corresponding queue according to the dot1p-lp mapping table. QCN takes effect only on that queue. Packets with other CNPVs cannot enter the queue.
You can specify an alternate priority value for a CND. If a frame from outside the CND includes the CNPV, the 802.1p priority value of the frame is mapped to the alternate priority value.
For information about the default dot1p-lp mapping table, see "Configuring priority mapping."
CND defense mode
After a device is assigned to a CND, each interface on the device has a defense mode, which is statically configured or negotiated through LLDP.
The following defense modes are available:
· disabled—Disables congestion notification and performs priority mapping according to the priority mapping table.
· edge—Maps the priority of incoming frames with a CNPV to an alternate priority. A CP removes CN tags before sending out the frames.
· interior—Does not alter the priority of incoming frames with a CNPV and performs priority mapping according to the default dot1p-lp priority mapping table. A CP removes CN tags before sending out the frames.
· interiorReady—Does not alter the priority of incoming frames with a CNPV and performs priority mapping according to the default dot1p-lp priority mapping table. A CP retains CN tags when sending out the frames.
Protocols and standards
IEEE 802.1Qau, Congestion notification
Restrictions and guidelines: QCN configuration
· Modifying the priority mapping table for traffic with a CNPV might cause the system to fail to detect congestion for the CNPV.
· When you map multiple 802.1p priorities to one queue, all packets with these 802.1p priorities will be included when congestion conditions are monitored. Therefore, do not map 802.1p priorities not enabled with QCN to a queue enabled with QCN.
· The influence of the primap and marking actions configured in QoS policies on priority mapping varies by device model.
· The priority trust mode must be configured as the 802.1p priority. For information about configuring trust modes, see "Configuring priority mapping."
QCN tasks at a glance
To configure QCN, perform the following tasks:
1. Enabling QCN
a. Configuring global CND settings
b. (Optional.) Configuring CND settings for an interface
3. (Optional.) Applying a congestion detection profile
Prerequisites for QCN configuration
Before you configure QCN, enable LLDP. For more information about LLDP, see Layer 2—LAN Switching Configuration Guide.
Enabling QCN
Restrictions and guidelines
When QCN is disabled, the following events occur:
· All QCN settings become invalid but still exist.
· The device stops LLDP negotiation and does not process or carry CN TLVs in LLDP packets.
Procedure
1. Enter system view.
system-view
2. Enable QCN.
qcn-enable
By default, QCN is disabled.
Configuring CND settings
About CND settings
CND settings include interface-level CND settings and global CND settings. You must configure global CND settings before configuring interface-level CND settings.
Global CND settings assign all interfaces on a device to a CND identified by the specified CNPV.
After you assign all interfaces on a device to a CND, the device can detect congestion for packets within the CND.
Interface-level CND settings assign different interfaces to different CNDs to meet your granular requirements.
You can assign a device to multiple CNDs by specifying multiple CNPVs for the device. For example, a device can be assigned to CND 1, CND 2, and CND 3 and have an alternate priority of 0 in all three CNDs. Table 1 shows priority mappings.
dot1p |
CNPV |
Alternate priority |
0 |
N/A |
N/A |
1 |
1 |
0 |
2 |
2 |
0 |
3 |
3 |
0 |
4 |
N/A |
N/A |
5 |
N/A |
N/A |
6 |
N/A |
N/A |
7 |
N/A |
N/A |
Configuring global CND settings
1. Enter system view.
system-view
2. Configure global CND settings.
qcn priority priority { admin [ defense-mode { disabled | edge | interior | interior-ready } alternate alternate-value ] | auto }
By default, a device does not belong to any CND.
Configuring CND settings for an interface
1. Enter system view.
system-view
2. Enter interface view.
interface interface-type interface-number
3. Configure CND settings for the interface.
qcn port priority priority { admin [ defense-mode { disabled | edge | interior | interior-ready } alternate alternate-value ] | auto }
By default, the global CND settings apply.
Applying a congestion detection profile
About this task
A congestion detection profile includes a desired queue length and a weight value. The device calculates the congestion status based on the congestion detection profile.
Procedure
1. Enter system view.
system-view
2. Create a congestion detection profile.
qcn profile profile-id
By default, congestion detection profile 0 exists.
The system automatically creates the default congestion detection profile (profile 0), which has a desired queue length of 26000 bytes and a weight value of 1. You cannot modify the default profile.
3. Bind the congestion detection profile to a CND.
qcn priority priority profile profile-id
By default, the default profile is bound to a CND.
Display and maintenance commands for QCN
Execute display commands in any view and reset commands in user view.
Task |
Command |
Display CP statistics for an interface. |
display qcn cp interface [ interface-type interface-number ] [ priority priority ] |
Display global CND settings. |
display qcn global [ slot slot-number ] |
Display the CND settings for an interface. |
display qcn interface [ interface-type interface-number ] |
Display profile settings. |
display qcn profile [ profile-id | default ] [ slot slot-number ] |
Clear CP statistics for an interface. |
reset qcn cp interface [ interface-type interface-number ] [ priority priority ] |
QCN configuration examples
Example: Configuring basic QCN
Network configuration
As shown in Figure 6, RP 1 and RP 2 are in the same VLAN and both support QCN.
Configure QCN for CNPV 1 to meet the following requirements:
· Switch A, Switch B, and Switch C detect congestion for traffic with 802.1p priority 1.
· Switch A, Switch B, and Switch C do not detect congestion for all other traffic.
Procedure
1. Configure Switch A:
# Create VLAN 100, and assign Ten-GigabitEthernet 1/0/1 to the VLAN.
<SwitchA> system-view
[SwitchA] vlan 100
[SwitchA-vlan100] port ten-gigabitethernet 1/0/1
[SwitchA-vlan100] quit
# Configure Ten-GigabitEthernet 1/0/2 as a trunk port, and assign it to VLAN 100.
[SwitchA] interface ten-gigabitethernet 1/0/2
[SwitchA-Ten-GigabitEthernet1/0/2] port link-type trunk
[SwitchA-Ten-GigabitEthernet1/0/2] port trunk permit vlan 100
[SwitchA-Ten-GigabitEthernet1/0/2] quit
# Enable LLDP globally.
[SwitchA] lldp global enable
# Enable CN TLV advertising on Ten-GigabitEthernet 1/0/1.
[SwitchA] interface ten-gigabitethernet 1/0/1
[SwitchA-Ten-GigabitEthernet1/0/1] lldp tlv-enable dot1-tlv congestion-notification
[SwitchA-Ten-GigabitEthernet1/0/1] quit
# Enable CN TLV advertising on Ten-GigabitEthernet 1/0/2.
[SwitchA] interface ten-gigabitethernet 1/0/2
[SwitchA-Ten-GigabitEthernet1/0/2] lldp tlv-enable dot1-tlv congestion-notification
[SwitchA-Ten-GigabitEthernet1/0/2] quit
# Enable QCN.
[SwitchA] qcn enable
# Assign the switch to the CND with CNPV 1, and configure all interfaces to negotiate the defense mode and alternate priority by using LLDP.
[SwitchA] qcn priority 1 auto
2. Configure Switch B:
# Create VLAN 100.
<SwitchB> system-view
[SwitchB] vlan 100
[SwitchB-vlan100] quit
# Configure the following interfaces as trunk ports, and assign all of them to VLAN 100:
¡ Ten-GigabitEthernet 1/0/1.
¡ Ten-GigabitEthernet 1/0/2.
¡ Ten-GigabitEthernet 1/0/3.
[SwitchB] interface ten-gigabitethernet 1/0/1
[SwitchB-Ten-GigabitEthernet1/0/1] port link-type trunk
[SwitchB-Ten-GigabitEthernet1/0/1] port trunk permit vlan 100
[SwitchB-Ten-GigabitEthernet1/0/1] quit
[SwitchB] interface ten-gigabitethernet 1/0/2
[SwitchB-Ten-GigabitEthernet1/0/2] port link-type trunk
[SwitchB-Ten-GigabitEthernet1/0/2] port trunk permit vlan 100
[SwitchB-Ten-GigabitEthernet1/0/2] quit
[SwitchB] interface ten-gigabitethernet 1/0/3
[SwitchB-Ten-GigabitEthernet1/0/3] port link-type trunk
[SwitchB-Ten-GigabitEthernet1/0/3] port trunk permit vlan 100
[SwitchB-Ten-GigabitEthernet1/0/3] quit
# Enable LLDP globally.
[SwitchB] lldp global enable
# Enable CN TLV advertising on Ten-GigabitEthernet 1/0/1 and Ten-GigabitEthernet 1/0/3.
[SwitchB] interface ten-gigabitethernet 1/0/1
[SwitchB-Ten-GigabitEthernet1/0/1] lldp tlv-enable dot1-tlv congestion-notification
[SwitchB-Ten-GigabitEthernet1/0/1] quit
[SwitchB] interface ten-gigabitethernet 1/0/3
[SwitchB-Ten-GigabitEthernet1/0/3] lldp tlv-enable dot1-tlv congestion-notification
[SwitchB-Ten-GigabitEthernet1/0/3] quit
# Enable QCN.
[SwitchB] qcn enable
# Assign the switch to the CND with CNPV 1.
[SwitchB] qcn priority 1 auto
# Configure the CND defense mode edge and alternate value 0 for interface Ten-GigabitEthernet 1/0/2.
[SwitchB-Ten-GigabitEthernet1/0/2] qcn port priority 1 admin defense-mode edge alternate 0
[SwitchB-Ten-GigabitEthernet1/0/2] quit
# Assign the switch to the CND with CNPV 1, and configure all interfaces to negotiate the defense mode and alternate priority by using LLDP.
[SwitchB] qcn priority 1 auto
3. Configure Switch C in the same way Switch A is configured. (Details not shown.)
Verifying the configuration
# Display the CND settings for interfaces on Switch A.
[SwitchA] display qcn interface
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
# Display the CND settings for interfaces on Switch B.
[SwitchB] display qcn interface
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 admin edge 0
Interface: XGE1/0/3
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
# Display the CND settings for interfaces on Switch C.
[SwitchC] display qcn interface
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
Example: Configuring MultiCND QCN
Network configuration
As shown in Figure 7:
· RP 1 and RP 2 are in the same VLAN.
· RP 3 and RP 4 are in the same VLAN.
· RP 1, RP 2, Switch A, Switch B, and Switch C form a CND with CNPV 1.
· RP 3, RP 4, Switch C, Switch D, and Switch E form a CND with CNPV 5.
Configure QCN for CNPV 1 to meet the following requirements:
· Switch A, Switch B, and Switch C detect congestion for traffic with 802.1p priority 1.
· Switch A and Switch B do not detect congestion for traffic with 802.1p priority 5.
Configure QCN for CNPV 5 to meet the following requirements:
· Switch C, Switch D, and Switch E detect congestion for traffic with 802.1p priority 5.
· Switch D and Switch E do not detect congestion for traffic with 802.1p priority 1.
Procedure
1. Configure Switch A:
# Create VLAN 100, and assign Ten-GigabitEthernet 1/0/1 to the VLAN.
<SwitchA> system-view
[SwitchA] vlan 100
[SwitchA-vlan100] port ten-gigabitethernet 1/0/1
[SwitchA-vlan100] quit
# Configure Ten-GigabitEthernet 1/0/2 as a trunk port, and assign it to VLAN 100.
[SwitchA] interface ten-gigabitethernet 1/0/2
[SwitchA-Ten-GigabitEthernet1/0/2] port link-type trunk
[SwitchA-Ten-GigabitEthernet1/0/2] port trunk permit vlan 100
[SwitchA-Ten-GigabitEthernet1/0/2] quit
# Enable LLDP globally.
[SwitchA] lldp global enable
# Enable CN TLV advertising on Ten-GigabitEthernet 1/0/1.
[SwitchA] interface ten-gigabitethernet 1/0/1
[SwitchA-Ten-GigabitEthernet1/0/1] lldp tlv-enable dot1-tlv congestion-notification
[SwitchA-Ten-GigabitEthernet1/0/1] quit
# Enable CN TLV advertising on Ten-GigabitEthernet 1/0/2.
[SwitchA] interface ten-gigabitethernet 1/0/2
[SwitchA-Ten-GigabitEthernet1/0/2] lldp tlv-enable dot1-tlv congestion-notification
[SwitchA-Ten-GigabitEthernet1/0/2] quit
# Enable QCN.
[SwitchA] qcn enable
# Assign the switch to the CND with CNPV 1, and configure all interfaces to negotiate the defense mode and alternate priority by using LLDP.
[SwitchA] qcn priority 1 auto
2. Configure Switch B in the same way Switch A is configured. (Details not shown.)
3. Configure Switch C:
# Create VLAN 100 and VLAN 200.
<SwitchC> system-view
[SwitchC] vlan 100
[SwitchC-vlan100] quit
[SwitchC] vlan 200
[SwitchC-vlan200] quit
# Configure the following interfaces as trunk ports, and assign all of them to VLAN 100 and VLAN 200:
¡ Ten-GigabitEthernet 1/0/1.
¡ Ten-GigabitEthernet 1/0/2.
¡ Ten-GigabitEthernet 1/0/3.
¡ Ten-GigabitEthernet 1/0/4.
[SwitchC] interface ten-gigabitethernet 1/0/1
[SwitchC-Ten-GigabitEthernet1/0/1] port link-type trunk
[SwitchC-Ten-GigabitEthernet1/0/1] port trunk permit vlan 100 200
[SwitchC-Ten-GigabitEthernet1/0/1] quit
[SwitchC] interface ten-gigabitethernet 1/0/2
[SwitchC-Ten-GigabitEthernet1/0/2] port link-type trunk
[SwitchC-Ten-GigabitEthernet1/0/2] port trunk permit vlan 100 200
[SwitchC-Ten-GigabitEthernet1/0/2] quit
[SwitchC] interface ten-gigabitethernet 1/0/3
[SwitchC-Ten-GigabitEthernet1/0/3] port link-type trunk
[SwitchC-Ten-GigabitEthernet1/0/3] port trunk permit vlan 100 200
[SwitchC-Ten-GigabitEthernet1/0/3] quit
[SwitchC] interface ten-gigabitethernet 1/0/4
[SwitchC-Ten-GigabitEthernet1/0/4] port link-type trunk
[SwitchC-Ten-GigabitEthernet1/0/4] port trunk permit vlan 100 200
[SwitchC-Ten-GigabitEthernet1/0/4] quit
# Enable LLDP globally.
[SwitchC] lldp global enable
# Enable CN TLV advertising on the following interfaces:
¡ Ten-GigabitEthernet 1/0/1.
¡ Ten-GigabitEthernet 1/0/2.
¡ Ten-GigabitEthernet 1/0/3.
¡ Ten-GigabitEthernet 1/0/4.
[SwitchC] interface ten-gigabitethernet 1/0/1
[SwitchC-Ten-GigabitEthernet1/0/1] lldp tlv-enable dot1-tlv congestion-notification
[SwitchC-Ten-GigabitEthernet1/0/1] quit
[SwitchC] interface ten-gigabitethernet 1/0/2
[SwitchC-Ten-GigabitEthernet1/0/2] lldp tlv-enable dot1-tlv congestion-notification
[SwitchC-Ten-GigabitEthernet1/0/2] quit
[SwitchC] interface ten-gigabitethernet 1/0/3
[SwitchC-Ten-GigabitEthernet1/0/3] lldp tlv-enable dot1-tlv congestion-notification
[SwitchC-Ten-GigabitEthernet1/0/3] quit
[SwitchC] interface ten-gigabitethernet 1/0/4
[SwitchC-Ten-GigabitEthernet1/0/4] lldp tlv-enable dot1-tlv congestion-notification
[SwitchC-Ten-GigabitEthernet1/0/4] quit
# Enable QCN.
[SwitchC] qcn enable
# Assign the switch to the CNDs with CNPV 1 and CNPV 5.
[SwitchC] qcn priority 1 auto
[SwitchC] qcn priority 5 admin defense-mode interior-ready alternate 4
# Configure the CND defense mode edge and alternate value 4 for Ten-GigabitEthernet 1/0/1 and Ten-GigabitEthernet 1/0/2.
[SwitchC] interface ten-gigabitethernet 1/0/1
[SwitchC-Ten-GigabitEthernet1/0/1] qcn port priority 5 admin defense-mode edge alternate 4
[SwitchC-Ten-GigabitEthernet1/0/1] quit
[SwitchC] interface ten-gigabitethernet 1/0/2
[SwitchC-Ten-GigabitEthernet1/0/2] qcn port priority 5 admin defense-mode edge alternate 4
[SwitchC-Ten-GigabitEthernet1/0/2] quit
# Assign the switch to the CND with CNPV 1, and configure all interfaces to negotiate the defense mode and alternate priority by using LLDP.
[SwitchC] qcn priority 1 auto
4. Configure Switch D:
# Create VLAN 200, and assign Ten-GigabitEthernet 1/0/1 to the VLAN.
<SwitchD> system-view
[SwitchD] vlan 200
[SwitchD-vlan200] port ten-gigabitethernet 1/0/1
[SwitchD-vlan200] quit
# Configure Ten-GigabitEthernet 1/0/2 as a trunk port, and assign it to VLAN 200.
[SwitchD] interface ten-gigabitethernet 1/0/2
[SwitchD-Ten-GigabitEthernet1/0/2] port link-type trunk
[SwitchD-Ten-GigabitEthernet1/0/2] port trunk permit vlan 200
[SwitchD-Ten-GigabitEthernet1/0/2] quit
# Enable QCN.
[SwitchD] qcn enable
# Assign the switch to the CND with CNPV 5.
[SwitchD] qcn priority 5 admin defense-mode interior-ready alternate 4
5. Configure Switch E in the same way Switch D is configured. (Details not shown.)
Verifying the configuration
# Display the CND settings for interfaces on Switch A.
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
# Display the CND settings for interfaces on Switch B.
[SwitchB] display qcn interface
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
# Display the CND settings for interfaces on Switch C.
[SwitchC] display qcn interface
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
5 admin edge 4
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp interior-ready 0
5 admin edge 4
Interface: XGE1/0/3
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp edge 0
5 comp interior-ready 4
Interface: XGE1/0/4
CNPV Mode Defense-mode Alternate
---------------------------------------------------
1 comp edge 0
5 comp interior-ready 4
# Display the CND settings for interfaces on Switch D.
[SwitchD] display qcn interface
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
5 comp interior-ready 4
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
5 comp interior-ready 4
# Display the CND settings for interfaces on Switch E.
[SwitchE] display qcn interface
Interface: XGE1/0/1
CNPV Mode Defense-mode Alternate
---------------------------------------------------
5 comp interior-ready 4
Interface: XGE1/0/2
CNPV Mode Defense-mode Alternate
---------------------------------------------------
5 comp interior-ready 4