QoS on Link Bundles
A bundle is a group of one or more ports that are aggregated together and treated as a single link. The router supports Ethernet interfaces and VLAN interfaces (bundle sub-interfaces) bundles. All QoS features currently supported on physical interfaces, are also supported on all link bundle interfaces. Applying QoS on bundle members is not supported.
 Note |
From Cisco IOS XR Release 7.3.1 onwards, systems with Cisco NC57 line cards running in compatibility mode support QoS over Layer 2 services for:
Starting with Cisco IOS XR Release 7.4.1 systems with Cisco NC57 line cards running in native mode support QoS over Layer 2 services for:
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Restrictions for Link Bundles
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Only Ethernet link bundling is supported.
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A bundle interface can only contain physical interface.
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All links within a single bundle must be configured either to run 802.3ad (LACP) or Etherchannel (non-LACP). Mixed links within a single bundle are not supported.
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MAC accounting is not supported on Ethernet link bundles.
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Maximum number of links supported in each link bundle is 64.
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The maximum number of link bundles supported is 128.
Load Balancing
Load balancing function is a forwarding mechanism to distribute traffic over multiple links based on Layer 3 routing information in the router. Per-destination load balancing isonly supported on the router, where the router is allowed to distribute packets over one of the links in the bundle. When the per-destination load balancing is enabled, all packets for a certain source-destination pair goes through the same link, though there are multiple links available. In other words, per-destination load balancing can ensure that packets for a certain source-destination pair could arrive in order.
Layer 3 Load Balancing on Link Bundles
Layer 3 load balancing for link bundles is done on Ethernet Flow Points (EFPs) and is based on the IPv4 source and destination addresses in the packet. When Layer 3 service-specific load balancing is configured, all egress bundles are load balanced based on the IPv4 source and destination addresses. When packets do not have IPv4 addresses, default load-balancing (based on the MAC SA/DA fields in the packet header) is used.
Configure QoS on Link Bundles
QoS is configured on link bundles in the same way that it is configured on individual interfaces.
Guidelines
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When a QoS policy is applied on a bundle in the egress direction, it’s also applied at each member interface.
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When a QoS policy is applied on a bundle (ingress direction), it’s replicated at each NPU core.
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If a QoS policy is not applied to a bundle interface, both the ingress and egress traffic use the default queue of the per link member port.
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The shape rate that is specified in the bundle policy-map is not an aggregate for all bundle members. The shape rate applied to the bundle depends on the load balancing of the links. For example, if a policy map with a shape rate of 10 Mbps is applied to a bundle with two member links, and if the traffic is always load-balanced to the same member link, then an overall rate of 10 Mbps applies to the bundle. However, if the traffic is load-balanced evenly between the two links, the overall shape rate for the bundle becomes 20 Mbps.
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If a member is deleted from a bundle, the total bundle statistics changes because the statistics that belongs to the detached link is lost.
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The QoS policy that is applied on bundle is inherited to all its member links and the reference bandwidth that is used to calculate shaper/bandwidth is applied as per the physical member interface bandwidth, and not the bundle as a whole.
Configuration Example
You have to accomplish the following to complete the QoS configuration on link bundles:
Note |
The policy works only if it is applied on the ingress direction. The egress is supported on COS, DEI and MPLS exp marking. So the below policy may not work when it is applied on egress. |
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Creating a class-map
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Creating a policy-map and specifying the respective class-map
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Specifying the action type for the traffic
Refer Attach a Traffic Policy to an Interface for details on step 1, 2 and 3.
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Creating a link bundle
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Applying traffic policy to the link bundle
/* Configure Ether-Bundle and apply traffic policy */
Router(config)# interface Bundle-Ether 12000
Router(config-if)# mtu 9100
Router(config-if)# service-policy input ingress
Router(config-if)# service-policy output egress
Router(config-if)# ipv4 address 100.12.0.0 255.255.255.254
Router(config-if)# bundle maximum-active links 64
Router(config-if)# commit
Running Configuration
This example shows how a traffic policy is applied on an Ethernet link bundle. The policy is applied to all interfaces that are members of the Ethernet link bundle.
/* Policy-map */
policy-map ingress
class inet4-classifier-af1
set qos-group 1
!
class inet4-classifier-af2
set qos-group 2
!
class inet4-classifier-af3
set qos-group 3
!
class inet4-classifier-af4
set qos-group 4
!
class inet4-classifier-be1
set qos-group 5
!
class inet4-classifier-nc1
set qos-group 6
!
class class-default
!
end-policy-map
!
/* Ether Bundle */
interface Bundle-Ether12000
mtu 9100
service-policy input ingress
service-policy output egress
ipv4 address 100.12.0.0 255.255.255.254
load-interval 30
flow ipv4 monitor FMM-V4 sampler SM ingress
flow ipv6 monitor FMM-V6 sampler SM ingress
flow mpls monitor FMM-MPLS sampler SM ingress
ipv4 access-group IPV4ACL_101 ingress
ipv6 access-group IPV6ACL_101 ingress
!
Verification
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Verify that the bundle status is UP.
router# show bundle bundle-ether 1200 Wed Dec 16 19:55:49.974 PST Bundle-Ether12000 Status: Up Local links <active/standby/configured>: 35 / 0 / 35 Local bandwidth <effective/available>: 3500000000 (3500000000) kbps MAC address (source): ea3b.745f.c4b0 (Chassis pool) Inter-chassis link: No Minimum active links / bandwidth: 1 / 1 kbps Maximum active links: 64 Wait while timer: 2000 ms Load balancing: Default LACP: Operational Flap suppression timer: Off Cisco extensions: Disabled Non-revertive: Disabled mLACP: Not configured IPv4 BFD: Not configured Port Device State Port ID B/W, kbps -------------------- --------------- ----------- -------------- ---------- Hu0/4/0/0 Local Active 0x8000, 0x0009 100000000 Link is Active Hu0/4/0/1 Local Active 0x8000, 0x000a 100000000 Link is Active - - - - - - Hu0/4/0/35 Local Active 0x8000, 0x002b 100000000 Link is Active -
Verify the bundle statistics:
router# show policy-map interface bundle-ether 12000 Bundle-Ether12000 input: ingress Class inet4-classifier-af1 Classification statistics (packets/bytes) (rate - kbps) Matched : 4647401962/21236124455654 26403040 Transmitted : 4647401962/21236124455654 26403040 Total Dropped : 0/0 0 Class inet4-classifier-af2 Classification statistics (packets/bytes) (rate - kbps) Matched : 4502980177/20576584333939 25571493 Transmitted : 4502980177/20576584333939 25571493 Total Dropped : 0/0 0 Class inet4-classifier-af3 Classification statistics (packets/bytes) (rate - kbps) Matched : 4647404125/21236213667880 26389086 Transmitted : 4647404125/21236213667880 26389086 Total Dropped : 0/0 0 Class inet4-classifier-af4 Classification statistics (packets/bytes) (rate - kbps) Matched : 9291188840/42456120548683 52771168 Transmitted : 9291188840/42456120548683 52771168 Total Dropped : 0/0 0 Class inet4-classifier-be1 Classification statistics (packets/bytes) (rate - kbps) Matched : 4647413429/21235847852686 26393414 Transmitted : 4647413429/21235847852686 26393414 Total Dropped : 0/0 0 Class inet4-classifier-nc1 Classification statistics (packets/bytes) (rate - kbps) Matched : 9294887621/42473100149807 52778258 Transmitted : 9294887621/42473100149807 52778258 Total Dropped : 0/0 0 Class class-default Classification statistics (packets/bytes) (rate - kbps) Matched : 0/0 0 Transmitted : 0/0 0 Total Dropped : 0/0 0 Bundle-Ether12000 output: egress Class c1 Classification statistics (packets/bytes) (rate - kbps) Matched : 16665494532/75878118942463 8760591 Transmitted : 16655834643/75834136022017 8760591 Total Dropped : 9659889/43982920446 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 9659889/43982920446 Class c2 Classification statistics (packets/bytes) (rate - kbps) Matched : 16665421959/75877849543188 8718687 Transmitted : 16665421959/75877849543188 8718687 Total Dropped : 0/0 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 0/0 Class c3 Classification statistics (packets/bytes) (rate - kbps) Matched : 16665247833/75877509455458 8703470 Transmitted : 16665187414/75877234624197 8703470 Total Dropped : 60419/274831261 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 60419/274831261 Class c4 Classification statistics (packets/bytes) (rate - kbps) Matched : 33330896131/151755393012945 17470745 Transmitted : 33330745421/151754709368565 17470745 Total Dropped : 150710/683644380 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 150710/683644380 Class c5 Classification statistics (packets/bytes) (rate - kbps) Matched : 16878910340/76849791869834 8833394 Transmitted : 16878849464/76849514633309 8833394 Total Dropped : 60876/277236525 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 60876/277236525 Class c6 Classification statistics (packets/bytes) (rate - kbps) Matched : 33330898844/151756094112925 17456785 Transmitted : 33330752668/151755427708382 17456785 Total Dropped : 146176/666404543 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 146176/666404543 Class c7 Classification statistics (packets/bytes) (rate - kbps) Matched : 244106/79922040 74 Transmitted : 244106/79922040 74 Total Dropped : 0/0 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 0/0 Class class-default Classification statistics (packets/bytes) (rate - kbps) Matched : 267075066180/1215993441123215 139917482 Transmitted : 267075066180/1215993441123215 139917482 Total Dropped : 0/0 0 Queueing statistics Queue ID : None (Bundle) Taildropped(packets/bytes) : 0/0
Related Topics
Associated Commands
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bundle maximu-active links
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interface Bundle-Ether
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