http://austecjenni.blogspot.com/2018/10/cisco-3850-layer-3-egress-wan-qos.html
1. Configure class-map first (class-map matches the tags)
class-map match-any VOICE-RTP
match dscp ef
class-map match-any VIDEO-INTERACTIVE
match dscp af41
match dscp cs4
class-map match-any CALL-SIGNALING
match ip dscp cs3
match ip dscp af31
class-map match-any SCAVENGER
match ip dscp cs1
2. Then Policy-map allocates percentage of bandwidth & reservations based on class
policy-map WAN-PRIMARY
class VOICE-RTP
priority level 1 percent 10
class VIDEO-INTERACTIVE
priority level 2 percent 20
class CALL-SIGNALING
bandwidth percent 5
class SCAVENGER
bandwidth percent 10
class class-default
shape average 9500000000***
Then Service-policy applies policy-map to interface
interface Gi1/0/1
service-policy output WAN-PRIMARY
Note: ***shape average should be lowered by bandwidth minus 5 percent, in bits for 1Gb it would be 950Mb the five percent was rule of thumb for 100Mb so took 1Gbps knocked it down to 950Mb for gig it's 950 million = 950,000,000 bits, and 95Mb shape average for 100Mb circuit Bits Per Second Cheatsheet: 1 Kbps = 1,000 bps (one thousand bits per second) 100 Kbps = 100,000 bps (100 thousand) 1 Mbps = 1,000,000 bps (1 million) 100 Mbps = 100,000,000 bps (100 million) 1 Gbps = 1,000,000,000 bps (1 billion) 10 Gbps = 10,000,000,000 bps (10 billion)
https://blog.ine.com/2013/05/06/cisco-catalyst-3850-qos-quick-note
class-map match-any test
match vlan 15
!
policy-map test
class test
police cir 512000
!
interface GigabitEthernet1/0/5
switchport mode trunk
load-interval 30
service-policy input test
Not only is it extremely simple to configure and intuitive from an IOS perspective
but you actually get output from the show policy-map command.
Rack1SW1#sho policy-map interface g1/0/5
GigabitEthernet1/0/5
Service-policy input: test
Class-map: test (match-any)
Match: vlan 15
police:
cir 512000 bps, bc 16000 bytes
conformed 18935704 bytes; actions:
transmit
exceeded 761225593 bytes; actions:
drop
conformed 0000 bps, exceed 0000 bps
Class-map: class-default (match-any)
Match: any
Rack1SW1#
access-list 1 permit xx.xx.xx.xx 0.0.0.255
class-map match-all voice
match access-group 1 #access-list 1
policy-map voice-protect
class voice
set ip dscp 40
interface GigabitEthernet 0/1
service-policy input voice-protect
ip access-list extended acl-ope
permit ip any 10.20.20.0 0.255.255.255
class-map match-all class-ope
match access-group acl-ope
policy-map policy-ope
class class-ope
set ip precedence 5
interface FastEthernet 0/1
service-policy output class-ope
policy-map policy1
class class1
bandwidth 1000
queue-limit 20
class class2
bandwidth 2000
access-list 100 permit tcp 172.16.0.0 0.15.255.255 any eq 80
access-list 101 permit tcp 192.168.0.0 0.0.255.255 any eq 80
class-map match-all QoS1
match access-group 100
class-map match-all QoS2
match access-group 101
policy-map QoS
class QoS1
bandwidth 10000 !トラフィックが輻輳した際に、10Mbpsの帯域が保証
class QoS2
bandwidth 20000 !トラフィックが輻輳した際に、20Mbpsの帯域が保証
interface Ethernet0/1
service-policy output QoS
設定内容の確認やパケット数の確認
# show policy-map interface fa0/0
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