Juniper EX Series Switch Workshop 筆記分享 Part II

這一份是大部份我在上課作Lab時Dump下來的指令，其中比較複雜的部份我加上了些許的註釋，希望對各位會有所幫助!

Initial Configuration with DHCP

system {
    root-authentication {
        encrypted-password "$1$2Ssh2j.s$0vlh/Jv7fu5xpueSmG8O1/"; ## SECRET-DATA
        ! 設定 root 登入密碼
    }
    login {
        user juniper {
            uid 2000;
            class super-user;
            authentication {
                encrypted-password "$1$AGAzBQkY$QWZ8BSLezx0d7Oh0j.NFw."; ## SECRET-DATA
            ! 設定使用者登入帳號密碼
            }
        }
    }
    services {
        ssh {
            root-login allow;
            ! 設定ssh telnet
        }
        web-management {
            http;
            ! 設定J-web access
        }
        dhcp {
            pool 192.168.200.0/24 {
                address-range low 192.168.200.101 high 192.168.200.110;
                router {
                    192.168.200.10;
                }   
            }       
            pool 192.168.3.0/24 {
                address-range low 192.168.3.101 high 192.168.3.105;
                router {
                    192.168.3.2;
                }   
            }       
        }
        ! 設定 DHCP Server
}


VLAN

root# set vlans Test vlan-id 100
! 設定VLAN 'Test' VLAN id 100

root# run show vlans 
Name           Tag     Interfaces
Test           100     
                       ae0.0, ae1.0, ge-0/0/0.0*, ge-0/0/1.0, ge-0/0/2.0,
                       ge-0/0/3.0
                       (* 代表實體port有connection)
Trust          300     
                       ae0.0, ae1.0, ge-0/0/12.0, ge-0/0/13.0, ge-0/0/14.0,
                       ge-0/0/15.0
default       
                       ge-0/0/16.0, ge-0/0/17.0, ge-0/0/21.0, ge-0/0/23.0
vlab           200     
                       ae0.0, ae1.0, ge-0/0/4.0, ge-0/0/5.0, ge-0/0/6.0,
                       ge-0/0/7.0, ge-0/0/8.0, ge-0/0/9.0, ge-0/0/10.0,
                       ge-0/0/11.0
                       
# run show system service dhcp
# run show vlans


LAG

root# set chassis aggregated-devices ethernet device-count 2
! 設定LAG有兩個groups

root# set interfaces ge-0/0/20 ether-options 802.3ad ae1  
! 設定 GE-0/0/20 成為LAG Group "ae1"的成員

root# set interfaces ae1 unit 0 family ethernet-switching port-mode trunk
! 設定LAG interface "ae1" 成為 Trunk Port

root# set interfaces ae1 unit 0 family ethernet-switching native-vlan-id 100
! 設定LAG interface ae1 Trunk native-vlan-id 100

root# set interfaces ae1 unit 0 family ethernet-switching vlan members 200
! 設定LAG interface ae1 Trunk 可通過VLAN id 200


IEEE 802.1d/802.1w/802.1s Spanning Tree

root#set protocol stp bridge-priority
root#set protocol stp hello-time
root#set protocol stp max-age

root#set protocol rstp bridge-priority
root#set protocol rstp hello-time
root#set protocol rstp max-age

#set protocols mstp bridge-priority 32k 
#set protocols mstp interface ae0.0 cost 1000 
#set protocols mstp interface ae0.0 mode point-to-point 
#set protocols mstp interface ae1.0 cost 1000 
#set protocols mstp interface ae1.0 mode point-to-point 
#set protocols mstp msti 1 bridge-priority 8k 
#set protocols mstp msti 1 vlan 100
#set protocols mstp msti 2 bridge-priority 4k 
#set protocols mstp msti 2 vlan 200 3

>show spanning-tree bridge 
>show spanning-tree mstp configuration
>show spanning-tree interface msti 

mstp {
    bridge-priority 32k;
    ! 設定本機priority 32000
    interface ae0.0 {
        cost 1000;  
        mode point-to-point;
        ! 設定LAG group1
    }               
    interface ae1.0 {
        cost 1000;  
        mode point-to-point;
        ! 設定LAG group1
    }               
    msti 1 {        
        bridge-priority 8k;
        vlan 100;
        ! 設定MSTP Instance 1 priority 8192, including VLAN 100
    }               
    msti 2 {        
        bridge-priority 4k;
        vlan [ 200 3 ];
        ! 設定MSTP Instance 2 priority 4096, including VLAN 200, 3

    }               
}


RTG

#ethernet-switching options redundant-group group-name TEST interface ge-0/0/0.0 primary

#ethernet-switching options redundant-group group-name TEST interface ge-0/0/0.0 (non-active)
#ethernet-switching options redundant-group group-name TEST interface ge-0/0/1.0 (active)

#ethernet-switching options redundant-group group-name TEST interface ge-0/0/0.0 
#ethernet-switching options redundant-group group-name TEST interface ge-0/0/1.0 primary (with pre-emption)

>show redundant-trunk-group

>edit protocol mstp


Virtual Chassis

>show virtual-chassis protocol interface

#set preprovisioned member 1 role line-card
#run request virtual-chassis vc-port set pic-slot 1 port 1 member 0


IEEE 802.1x Authentication

access {
    radius-server {
        192.168.1.10 {
            secret "$9$hymcK8-ds4JDwY"; ## SECRET-DATA
            timeout 3;
            retry 1;
        }
    }
    profile dot1x-lab {
        authentication-order radius;
        radius {
            authentication-server 192.168.1.10;
        }
    }
}

protocols {
    lldp {
        interface all;
    }
    dot1x {
        traceoptions {
        ! trace debug output
            file dotxlog;
            flag dot1x-debug;
            flag eapol;
        }
        authenticator {
            static {
                00:16:d3:33:aa:11 {
                    vlan-assignment 200;
                }   
            }       
            interface {
                ge-0/0/16.0 {
                    supplicant single-secure;
                    guest-vlan 3;
                }
                ge-0/0/17.0 {
                    supplicant single-secure;
                    retries 2;
                    maximum-requests 2;
                    guest-vlan 3;
                }
                ge-0/0/21.0 {
                    supplicant single-secure;
                    guest-vlan 3;
                }
                ge-0/0/23.0 {
                    supplicant single-secure;
                    guest-vlan 3;
                }
            }
        }
    }
}



juniper# run show vlans 
Name           Tag     Interfaces
Test           100     
                       ae0.0, ae1.0, ge-0/0/0.0, ge-0/0/1.0, ge-0/0/2.0, ge-0/0/3.0
Trust          3       
                       ae0.0, ae1.0, ge-0/0/12.0, ge-0/0/13.0, ge-0/0/14.0, ge-0/0/15.0, ge-0/0/23.0*
default       
                       ge-0/0/16.0, ge-0/0/17.0, ge-0/0/21.0, ge-0/0/23.0*
                       ! because ge-0/0/23.0 IEEE 802.1x authentication fail so change vlan membership to guest vlan 3
vlab           200     
                       ae0.0, ae1.0, ge-0/0/4.0*, ge-0/0/5.0, ge-0/0/6.0, ge-0/0/7.0, ge-0/0/8.0, ge-0/0/9.0,
                       ge-0/0/10.0, ge-0/0/11.0


IEEE 802.1x

# set protocol dot1x transactions file dotxlog
# set protocol dot1x transactions flag dot1
# run show log
# run monitor start
# run monitor stop

juniper# show ethernet-switching-options
analyzer VLANSPAN {
    input {
        ingress {
            interface ge-0/0/1.0;
            interface ge-0/0/2.0;
            vlan Trust;
        }
        egress {
            interface ge-0/0/1.0;
            interface ge-0/0/2.0;
        }
    }
    output {
        interface {
            ge-0/0/5.0;
        }
    }
}


OSPF

juniper# show protocols ospf 
area 0.0.0.0 {
    interface vlan.100;
    interface ge-0/0/15.0;
}


Loopback interface

juniper# set interfaces lo0 unit 0 family inet address 1.1.1.1/32


LLDP

juniper# run show lldp neighbors 
LocalInterface Chassis Id        Port info     System Name
ge-0/0/14.0    00:1f:12:31:c1:40  ge-0/0/14.0  SW-R1        
ge-0/0/15.0    00:1f:12:31:c1:40  ge-0/0/15.0  SW-R1


QoS

# set class-of-service forwarding-classes class FF queue-num 5
# set class-of-service forwarding-classes class AF queue-num 1 
# set class-of-service forwarding-classes class BE queue-num 0
! 先定義Traffic Class對應的Queue Number

# set firewall family ethernet-switching filter QoS_Class term EF from source-address 192.168.3.200/32
# set firewall family ethernet-switching filter QoS_Class term EF from protocol udp destination-port 1234
# set firewall family ethernet-switching filter QoS_Class term EF then forwarding-class EF loss-priority low
# set firewall family ethernet-switching filter QoS_Class term AF from protocol tcp destination-port 80
# set firewall family ethernet-switching filter QoS_Class term AF then forwarding-class AF loss-priority low
# set firewall family ethernet-switching filter QoS_Class term BE then forwarding-class BE loss-priority high
! 再定義Filter QoS_Class整合不同的的Class，依據條件分別Assign至這些Class

# set interfaces ge-0/0/10 unit 0 family ethernet-switching filter input QoS_Class 
# set interfaces ge-0/0/11 unit 0 family ethernet-switching filter input QoS_Class 
! 在Physical Interface上套用Filter QoS_Class來進行Traffic Classification

# set class-of-service schedulers EF_Schedule priority strict-high 
# set class-of-service schedulers AF_Schedule transmit-rate percent 30
# set class-of-service schedulers AF_Schedule priority low
# set class-of-service schedulers BE_Schedule transmit-rate percent 60
# set class-of-service schedulers BE_Schedule priority high
! 準備接下來的scheduler(queueing)將會進行的動作

# set class-of-service scheduler-maps QoS_SCH_MAP forwarding-class EF scheduler EF_Schedule 
# set class-of-service scheduler-maps QoS_SCH_MAP forwarding-class AF scheduler AF_Schedule 
# set class-of-service scheduler-maps QoS_SCH_MAP forwarding-class BE scheduler BE_Schedule 
! 依據不同的Traffic Class套用之前定義好的scheduler，整合在同一個scheduler-maps QoS_SCH_MAP中

# set class-of-service interfaces ge-0/0/12 scheduler-map QoS_SCH_MAP
# set class-of-service interfaces ge-0/0/13 scheduler-map QoS_SCH_MAP 
! 將整合後的scheduler-map套用至physical interface


Final Configuration

juniper# show 
## Last changed: 2008-03-06 19:13:27 UTC
version 9.0R2.10;
system {
    root-authentication {
        encrypted-password "$1$ZlxV3U3G$llcI3VguUsmlwhqbto546."; ## SECRET-DATA
    }
    radius-server {
        192.168.1.10 {
            secret "$9$OIDZBcl8LNbYo7-"; ## SECRET-DATA
            timeout 5;
        }
    }
    login {
        user juniper {
            uid 2000;
            class super-user;
            authentication {
                encrypted-password "$1$AGAzBQkY$QWZ8BSLezx0d7Oh0j.NFw."; ## SECRET-DATA
            }
        }
    }
    services {
        ssh {
            root-login allow;
        }
        web-management {
            http;
        }
        dhcp {
            pool 192.168.200.0/24 {
                address-range low 192.168.200.101 high 192.168.200.110;
                router {
                    192.168.200.10;
                }   
            }
            pool 192.168.3.0/24 {
                address-range low 192.168.3.101 high 192.168.3.105;
                router {
                    192.168.3.2;
                }
            }
        }
    }
    syslog {
        user * {
            any emergency;
        }
        file messages {
            any notice;
            authorization info;
        }
        file interactive-commands {
            interactive-commands any;
        }
    }
}
chassis {
    aggregated-devices {
        ethernet {
            device-count 2;
        }
    }
}
interfaces {
    ge-0/0/0 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/1 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/2 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/3 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/4 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/5 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/6 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/7 {      
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/8 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/9 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/10 {
        unit 0 {
            family ethernet-switching {
                filter {
                    input QoS_Class;
                }
            }
        }
    }
    ge-0/0/11 {
        unit 0 {
            family ethernet-switching {
                filter {
                    input QoS_Class;
                }
            }
        }
    }
    ge-0/0/12 {     
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/13 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/14 {
        unit 0 {
            family ethernet-switching {
                port-mode access;
                vlan {
                    members 100;
                }
            }
        }
    }
    ge-0/0/15 {
        unit 0 {
            family inet {
                address 172.16.15.2/29;
            }
        }
    }
    ge-0/0/16 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/0/17 {
        unit 0 {    
            family ethernet-switching;
        }
    }
    ge-0/0/18 {
        ether-options {
            802.3ad ae0;
        }
    }
    ge-0/0/19 {
        ether-options {
            802.3ad ae0;
        }
    }
    ge-0/0/20 {
        ether-options {
            802.3ad ae1;
        }
    }
    ge-0/0/21 {
        unit 0 {
            family ethernet-switching {
                port-mode access;
            }
        }
    }
    ge-0/0/22 {
        ether-options {
            802.3ad ae1;
        }
    }
    ge-0/0/23 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/1/0 {
        unit 0 {
            family ethernet-switching;
        }
    }
    xe-0/1/0 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/1/1 {
        unit 0 {
            family ethernet-switching;
        }
    }
    xe-0/1/1 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/1/2 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ge-0/1/3 {
        unit 0 {
            family ethernet-switching;
        }
    }
    ae0 {           
        unit 0 {
            family ethernet-switching {
                port-mode trunk;
                vlan {
                    members [ Test vlab Trust ];
                }
            }
        }
    }
    ae1 {
        unit 0 {
            family ethernet-switching {
                port-mode trunk;
                vlan {
                    members [ 100 3 ];
                }
                native-vlan-id 200;
            }
        }
    }
    vlan {
        unit 3 {
            family inet {
                address 192.168.3.2/24;
            }
        }
        unit 100 {
            family inet {
                address 192.168.100.2/24;
            }
        }
        unit 200 {
            family inet {
                address 192.168.200.10/24;
            }
        }
    }
}
protocols {
    ospf {
        area 0.0.0.0 {
            interface vlan.100;
            interface ge-0/0/15.0;
        }
    }
    lldp {
        interface all;
    }
    dot1x {
        traceoptions {
            file dotxlog;
            flag dot1x-debug;
            flag eapol;
        }
        authenticator {
            authentication-profile-name dot1x-lab;
            static {
                00:16:d3:33:aa:11 {
                    vlan-assignment 200;
                }
            }
            interface {
                ge-0/0/16.0 {
                    supplicant single-secure;
                    guest-vlan 3;
                }   
                ge-0/0/17.0 {
                    supplicant multiple;
                    retries 2;
                    maximum-requests 2;
                    guest-vlan 3;
                }
                ge-0/0/21.0 {
                    supplicant single-secure;
                    guest-vlan 3;
                }
                ge-0/0/23.0 {
                    supplicant single-secure;
                    supplicant-timeout 10;
                    guest-vlan 3;
                }
            }
        }
    }
    mstp {
        bridge-priority 32k;
        interface ae0.0 {
            cost 1000;
            mode point-to-point;
        }
        interface ae1.0 {
            cost 1000;
            mode point-to-point;
        }
        msti 1 {
            bridge-priority 8k;
            vlan 100;
        }
        msti 2 {    
            bridge-priority 4k;
            vlan [ 200 3 ];
        }
    }
}
class-of-service {
    forwarding-classes {
        class EF queue-num 5;
        class AF queue-num 1;
        class BE queue-num 0;
        class NC queue-num 7;
    }
    interfaces {
        ge-0/0/12 {
            scheduler-map QoS_SCH_MAP;
        }
        ge-0/0/13 {
            scheduler-map QoS_SCH_MAP;
        }
    }
    scheduler-maps {
        QoS_SCH_MAP {
            forwarding-class EF scheduler EF_Schedule;
            forwarding-class AF scheduler AF_Schedule;
            forwarding-class BE scheduler BE_Schedule;
        }
    }
    schedulers {
        EF_Schedule {
            priority strict-high;
        }
        BE_Schedule {
            transmit-rate percent 60;
            priority low;
        }
        AF_Schedule {
            transmit-rate percent 30;
            priority low;
        }
    }
}
firewall {
    family ethernet-switching {
        filter QoS_Class {
            term EF {
                from {
                    source-address {
                        192.168.3.200/32;
                    }
                    protocol udp;
                    destination-port 1234;
                }
                then {
                    forwarding-class EF;
                    loss-priority low;
                }
            }
            term AF {
                from {
                    protocol tcp;
                    destination-port 80;
                }
                then {
                    forwarding-class AF;
                    loss-priority low;
                }   
            }
            term BE {
                then {
                    forwarding-class BE;
                    loss-priority high;
                }
            }
        }
    }
}
access {
    radius-server {
        192.168.1.10 {
            secret "$9$hymcK8-ds4JDwY"; ## SECRET-DATA
            timeout 3;
            retry 1;
        }
    }
    profile dot1x-lab {
        authentication-order radius;
        radius {
            authentication-server 192.168.1.10;
        }
    }
}
ethernet-switching-options {
    secure-access-port {
        interface ge-0/0/4.0 {
            dhcp-trusted;
        }
    }
    analyzer VLANSPAN {
        input {     
            ingress {
                interface ge-0/0/1.0;
                interface ge-0/0/2.0;
                vlan Trust;
            }
            egress {
                interface ge-0/0/1.0;
                interface ge-0/0/2.0;
            }
        }
        output {
            interface {
                ge-0/0/5.0;
            }
        }
    }
}
vlans {
    Test {
        vlan-id 100;
        interface {
            ge-0/0/0.0;
            ge-0/0/1.0;
            ge-0/0/2.0;
            ge-0/0/3.0;
        }
        l3-interface vlan.100;
    }
    Trust {
        vlan-id 3;
        interface {
            ge-0/0/12.0;
            ge-0/0/13.0;
        }
        l3-interface vlan.3;
    }
    vlab {
        vlan-id 200;
        interface {
            ge-0/0/4.0;
            ge-0/0/5.0;
            ge-0/0/6.0;
            ge-0/0/7.0;
            ge-0/0/8.0;
            ge-0/0/9.0;
            ge-0/0/10.0;
            ge-0/0/11.0;
        }
        l3-interface vlan.200;
    }
}
poe {
    interface all;
}

[edit]
juniper#

Comments

Post a Comment

Popular posts from this blog

TCP/IP 明確擁塞通知 (ECN)

Image
當路由器擁塞的程度已經達到填滿傳入封包緩衝區而開始捨棄封包時，會影響網路而縮減頻寬，對資料損失敏感或具時效性的傳輸量流動會進而受到衝擊，而且可能在擁塞之後產生連結閒置時間。TCP/IP 明確擁塞通知 (ECN) 讓路由器能夠通知「傳輸控制通訊協定」(TCP) 對等體，由於網路擁塞，緩衝區已滿。TCP 對等體會以減緩資料傳輸來回應，協助防止封包損失。 明確擁塞通知(Explicit Congestion Notification) TCP/IP 的 ECN 支援同時使用 IP 及 TCP 標頭中的未使用位元。 • 在 (IP) 網際網路層上，轉送封包時，傳送主機必須能夠表示有能力執行 ECN，而路由器則必須能夠指出所遇到的擁塞狀況。 • 在 (TCP) 傳輸層，TCP 對等體必須彼此表明有能力執行 ECN。接收端對等體必須能夠通知傳送端對等體，已經從遇到擁塞狀況的路由器接到封包；傳送端對等體必須能夠通知接收端對等體，已經從接收端對等體接到擁塞指標，並且已經降低傳輸速率。 IP 中的 ECN 支援 IP 標頭中的 8 位元 [Type of Service (TOS)] 欄位最先定義於 RFC 791 中，指出封包由路由器進行非預設傳送的傳送優先順序、延遲、輸送量、可靠性，以及成本等特性。TOS 欄位在 RFC 2474 中重新定義，以包含 6 位元區別服務代碼點 (Differentiated Services Code Point, DSCP) 及兩個未使用的位元。DSCP 值表示的傳送優先順序會對應於先前在內部網路的路由器中設定的佇列。IP 中的 ECN 支援使用 RFC 2474 所定義 TOS 欄位的兩個未使用位元。[圖 1] 顯示 ECN 中 TOS 欄位的新定義。 圖 1：ECN 中 TOS 欄位的新定義 RFC 2474 所定義 TOS 欄位中的兩個未使用位元在 RFC 3168 中定義為 ECN 欄位，欄位的值如下： • 00 傳送主機不支援 ECN。 • 01 或 10 傳送主機支援 ECN。 • 11 路由器已遇到擁塞狀況。 具備 ECN 功能的主機傳送其封包時，會將 ECN 欄位設定為 01 或 10。對於具備 ECN 功能的主機所傳送的封包，如果路徑中的路由器具備 ECN 功能，但是正遇到擁塞狀況，則 ECN 欄位會設定為 11。一旦 ECN
Read More »

集中式數位交換機(CENTREX)系統

一般公司行號採購電話系統時，大部分都是自行購置私用交換機（PBX）。其實除了PBX之外，亦可選擇電信公司提供的CENTREX電話系統。 所謂CENTREX電話系統，中文翻譯為「集中式數位交換機」，簡稱CENTREX虛擬總機。就是在電信公司在市話交換機上，附加用戶專用交換機（PBX）軟體的功能，使在CENTREX系統之各線獨用電話可兼有私用交換機的分機功能。在CENTREX系統中，電信公司將市話交換機的部分用戶定義為一個基本用戶群，該用戶群的用戶不僅擁有普通用戶的所有功能，而且擁有私用交換機的所有功能。CENTREX系統用戶的分機可以獨立計費，也不會因中繼數量不足而產生話路壅塞；除此之外，若同一公司有多個辦公地點，而均在同一市話交換機之供線範圍內，則全部之分機皆可以視為同一套總機之分機，這是一般私用交換機所不及的地方。以前因為CENTREX線路的申租費用較高、大部分是學校等建築物分散的用戶在使用。但隨著固網業務開放，CENTREX線路租用費用日益降低，將吸引人更多企業用戶捨棄自行建置PBX而改用CENTREX系統。 CENTREX系統的功能 一般來說，電信公司為CENTREX用戶提供下列一般及特殊功能： 一.外線直接撥入分機(DID) 不必另外申請，外線就可以直接撥入任一分機，分機亦可以不經總機之轉接，直接抓外線撥號。 二.分機限撥 每一分機可以做適當之限制，如限撥外線、長途、國際或限外線直接撥入分機等之各項限制。 三.電話轉接功能 當電話進來，完成通話之後，如要再找第三人時，可以利用本功能，將電話轉接到第三人，繼續通話而不必重撥。 四.來話保留(Call Hold) 接到電話時，如需要轉問其他人員，而不希望對方知道通話內容時，可以利用本功能將對方保留起來，進行詢問動作；完成後，在接回對方，繼續服務工作。 五.仲介電話功能 控制者可以利用本功能，自行控制要與甲方或乙方通話，當與甲方通話時，乙方成保留狀態，而聽不到甲方與控制者之通話內容；反之亦同。 六.呼叫代接功能 同一單位之電話可以設定為同一帶接群，當有同事不再位置上，而有電話進來時，可以利用呼叫代接功能代接其電話，而不必到他的位置上幫他接電話。 七.條件指定轉接 當電話忙線與電話進來而無法應答時，將電話轉到所設定之電話。 八.自動回叫(Call Back) 當你有急事要與對方聯繫，而對方又在電話中，不知對方何時完成
Read More »

WRR(Weighted Round Robin) vs SRR(Shared/Shaped Round Robin)

Image
在舊版的QoS 2.2中只有提到WRR(Weighted Round Robin)，但是在實務中，SRR已經漸漸在愈來愈多的Switch平台中使用，其中WRR與SRR最大的差別就是在於它們同時使用權重但是Scheduling的方式不同。 以下圖而言(暫不考慮Strict Priority Queue)，如果是用WRR的話，Queue 3的權重為4，所以每一輪都可以同時送出4個封包；Queue 2的權重為2，所以每一輪都可以同時送出2個封包；Queue 1的權重為1，所以每一次都可以同時送出1個封包。 如果是用SRR(Shared or Shaped Round Robin)的話，Queue 3的權重為4，Queue 2的權重為2，Queue 1的權重為1。因此Q3,Q2,Q1各出1個封包，接著Q3,Q2各出1個封包，再接著Q3出2個封包，這樣子才算是一輪。 所以SRR的好處在於每一個Queue很平均地送出封包前後穿插進入FIFO Queue(Hardware Queue)，而不是像WRR那樣一次出清每個Queue權重所佔比例數量的封包，這樣子下來的結果會讓不同Queue中的封包排程更加smooth，不會互相排擠。 SRR is a scheduling service for specifying the rate at which packets are dequeued. With SRR there are two modes, Shaped and Shared (default). Shaped mode is only available on the egress queues. Shaped egress queues reserve a set of port bandwidth and then send evenly spaced packets as per the reservation. Shared egress queues are also guaranteed a configured share of bandwidth, but do not reserve the bandwidth. That is, in Shared mode, if a higher priority queue is empty, instead
Read More »