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Lab 8-1 FEC

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    Lab 8-1 FEC

    Lab 8-1 FEC
    Mục đích
    Do các đường trunk giữa các Switch thường có băng thông không dủ lớn đo đó khôn đáp ứng được nhu cầu ở bên trong mạng dể gây ra nghẽn do đó mà người ta sử dụng Etherchannel để ghép nhiều đường trunk lạI thành một đường để tăng dung lượng, thứ hai là đối với các server có nhu cầu truy nhập cao do đó cũng cần một lượng băng thông lớn để tránh nghẽn, để ta sử ta cũng sử dụng Etherchannel.
    Nguyên tắc phân phối tải qua etherchannel:
    Việc phân phối tải qua các đường của một bundle (Etherchannel) được thực hiện theo thuật toán hashing: Thuật toán này có thể sử dụng : Địa chỉ IP nguồn, đích; Hoặc địa chỉ MAC nguồn, dích, hoặc có thể sử dụng TCP/UDP port. Nếu chỉ sử dụng một địa chỉ hay một port thì việc truyền tải qua port này hay port khác được thực hiện dựa vào các bit cuối cùng, và phụ thuộc vào số port của etherchannel. Nếu sử dụng cả địch, và nguồn thì thuật toán này được thực hiện nhờ phép toán XOR các bit cuối của địa chỉ.
    Các lệnh cơ bản để cấu hình Ethechannel
    Cấu hình PAGP Ethechannel:
    Switch(config-if)#channel-protocol pagp
    Switch(config-if)#channel-group number mode {on | auto | desirable }
    Các mode:
    ON mode: ở mode này thì Switch tự động enale etherchannel tuy nhiên nó lại không gởi hay nhận bất kỳ gói PAGP nào, do đó mà phải cấu hình on mode ở hai dầu
    Auto mode: Nó sẽ tự động enable ethechannel nếu nó nhận được PAGP packet.
    Desirable: Nó sẻ tự động cố gắng yêu cầu đầu kia enable ethechannel.
    Cấu hình LACP:
    Switch(config)#lacp system-priority priority
    Switch(config-if)#channel-protocol lacp
    Switch(config-if)#channel-group number mode {on | passive | active}
    Switch(config-if)# lacp port-priority priority
    Giải thích:
    Lệnh đầu tiên để xác định system priority để xác định Switch nào làm Switch điều khiển Ethechannel, hoặc nếu Priority bằng nhau thì Switch nào có điạc chỉ mac nhỏ hơn sẽ được chọn. Ta còn xác định priority của port để xác định xem port nào là active và port nào ở trạng thái standby. Port có priority nhỏ sẽ active và, lớn sẽ ở trạng thái standby. Các mode trong lệnh channel-group On, Passive, active tuần tự tương tự như On, Auto , Desirable trong PAGP
    Cấu hình Cho sơ đồ thực tế.



    Ở sơ đồ này ta lấy lại sơ đồ bài qos trứơc để thực hiện Etherchannel giữa Core va Access Switch. Ở đây thì ta sử dụng 4 port fastethernet 0/1 – 0/4 làm etherchannel, Ta sẽ cấu hình ehterchannel dùng cả PAGP, và LACP. Trước hết ta cấu hình PAGP.
    Cấu hình
    Show run
    Access#show run
    !
    hostname Access
    !
    enable password cisco
    !
    ip subnet-zero
    no ip domain-lookup
    !
    !
    spanning-tree mode pvst
    spanning-tree extend system-id
    !
    interface FastEthernet0/1
    switchport trunk encapsulation isl
    switchport mode trunk
    no ip address
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/2
    switchport trunk encapsulation isl
    switchport mode trunk
    no ip address
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/3
    switchport trunk encapsulation isl
    switchport mode trunk
    no ip address
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/4
    switchport trunk encapsulation isl
    switchport mode trunk
    no ip address
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/5
    switchport access vlan 2
    switchport mode access
    no ip address
    !
    interface FastEthernet0/6
    no ip address
    !
    interface FastEthernet0/7
    no ip address
    interface FastEthernet0/8
    no ip address
    !
    interface FastEthernet0/9
    no ip address
    !
    interface FastEthernet0/10
    no ip address
    !
    interface FastEthernet0/11
    no ip address
    !
    interface FastEthernet0/12
    no ip address
    !
    interface FastEthernet0/13
    no ip address
    !
    interface FastEthernet0/14
    no ip address
    !
    interface FastEthernet0/15
    no ip address
    !
    interface FastEthernet0/16
    no ip address
    !
    interface FastEthernet0/17
    no ip address
    !
    interface FastEthernet0/18
    no ip address
    !
    interface FastEthernet0/19
    no ip address
    !
    interface FastEthernet0/20
    no ip address
    !
    interface FastEthernet0/21
    no ip address
    !
    interface FastEthernet0/22
    no ip address
    !
    interface FastEthernet0/23
    no ip address
    !
    interface FastEthernet0/24
    no ip address
    !
    interface GigabitEthernet0/1
    no ip address
    !
    interface GigabitEthernet0/2
    no ip address
    !
    interface Vlan1
    ip address 192.168.5.2 255.255.255.0
    define interface-range cuong FastEthernet0/1 - 4
    !
    end

    Core
    !
    hostname Core

    enable password cisco
    !
    ip subnet-zero
    ip routing
    !
    no ip domain-lookup
    !
    spanning-tree mode pvst
    spanning-tree extend system-id
    !
    interface Port-channel1
    switchport trunk encapsulation isl
    switchport mode dynamic desirable
    !
    interface FastEthernet0/1
    switchport trunk encapsulation isl
    switchport mode dynamic desirable
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/2
    switchport trunk encapsulation isl
    switchport mode dynamic desirable
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/3
    switchport trunk encapsulation isl
    switchport mode dynamic desirable
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/4
    switchport trunk encapsulation isl
    switchport mode dynamic desirable
    duplex full
    speed 100
    channel-group 1 mode desirable
    !
    interface FastEthernet0/5
    no switchport
    ip address 192.168.3.2 255.255.255.0
    duplex half
    speed 100
    !
    interface FastEthernet0/6
    switchport mode dynamic desirable
    !
    interface FastEthernet0/7
    switchport mode dynamic desirable
    !
    interface FastEthernet0/8
    switchport mode dynamic desirable
    interface FastEthernet0/9
    switchport mode access
    !
    interface FastEthernet0/10
    switchport mode dynamic desirable
    !
    interface FastEthernet0/11
    switchport mode dynamic desirable
    !
    interface FastEthernet0/12
    switchport mode dynamic desirable
    !
    interface FastEthernet0/13
    switchport mode dynamic desirable
    !
    interface FastEthernet0/14
    switchport mode dynamic desirable
    !
    interface FastEthernet0/15
    switchport mode dynamic desirable
    !
    interface FastEthernet0/16
    switchport mode dynamic desirable
    !
    interface FastEthernet0/17
    switchport mode dynamic desirable
    !
    interface FastEthernet0/18
    switchport mode dynamic desirable
    !
    interface FastEthernet0/19
    switchport mode dynamic desirable
    !
    interface FastEthernet0/20
    switchport mode dynamic desirable
    !
    interface FastEthernet0/21
    switchport mode dynamic desirable
    !
    interface FastEthernet0/22
    switchport mode dynamic desirable
    !
    interface FastEthernet0/23
    switchport mode dynamic desirable
    !
    interface FastEthernet0/24
    switchport mode dynamic desirable
    !
    interface GigabitEthernet0/1
    switchport mode dynamic desirable
    !
    interface GigabitEthernet0/2
    switchport mode dynamic desirable
    !
    interface Vlan1
    ip address 192.168.5.1 255.255.255.0
    !
    interface Vlan2
    ip address 192.168.2.1 255.255.255.0
    define interface-range cuong FastEthernet0/1 - 4
    !
    router ospf 1
    log-adjacency-changes
    passive-interface Port-channel1
    network 192.168.2.0 0.0.0.255 area 0
    network 192.168.3.0 0.0.0.255 area 0
    !

    ip classless
    ip http server
    line con 0
    logging synchronous
    line vty 0 4
    password cisco
    no login
    line vty 5 15
    login
    !
    !
    monitor session 1 source interface Po1
    monitor session 1 destination interface Fa0/10
    end


    R1# show run
    Building configuration...

    Current configuration:
    !
    version 12.1
    service timestamps debug datetime msec
    service timestamps log datetime msec
    no service password-encryption
    !
    hostname R1
    !
    enable password cisco
    !

    memory-size iomem 10
    ip subnet-zero
    no ip domain-lookup
    !

    interface Loopback1
    ip address 11.1.1.1 255.255.255.0
    !
    interface Ethernet0/0
    ip address 192.168.1.1 255.255.255.0
    half-duplex
    !
    interface Serial0/0
    no ip address
    encapsulation frame-relay
    no fair-queue
    clockrate 64000
    !
    interface Serial0/0.122 point-to-point
    ip address 172.16.1.1 255.255.255.0
    frame-relay interface-dlci 122
    !
    interface Serial0/1
    no ip address
    shutdown
    !
    router ospf 1
    log-adjacency-changes
    network 11.0.0.0 0.0.0.255 area 0
    network 172.16.1.0 0.0.0.255 area 0
    network 192.168.1.0 0.0.0.255 area 0
    !
    ip classless
    ip http server
    !
    access-list 101 permit ip 192.168.1.0 0.0.0.255 192.168.3.0 0.0.0.255
    !
    line con 0
    logging synchronous
    transport input none
    line aux 0
    line vty 0 4
    no login
    !
    end

    R2
    !
    hostname R2
    !
    enable password cisco
    no ip domain-lookup
    !
    interface FastEthernet0/0
    ip address 192.168.3.1 255.255.255.0
    no ip directed-broadcast
    speed 100
    !
    interface Serial0/0
    no ip address
    no ip directed-broadcast
    encapsulation frame-relay
    no ip mroute-cache
    no fair-queue
    clockrate 64000
    cdp enable
    frame-relay lmi-type cisco
    !
    interface Serial0/0.221 point-to-point
    ip address 172.16.1.2 255.255.255.0
    no ip directed-broadcast
    frame-relay interface-dlci 221
    !
    router ospf 1
    network 172.16.1.0 0.0.0.255 area 0
    network 172.16.3.0 0.0.0.255 area 0
    network 0.0.0.0 255.255.255.255 area 0
    !
    router rip
    network 192.168.3.0
    !
    ip classless
    ip http server
    !
    access-list 101 permit ip 172.16.2.0 0.0.0.255 192.168.1.0 0.0.0.255
    !
    end
    Kiểm tra
    Show etherchannel port để xem trạng thái của tất cả các port trong group
    Core#show etherchannel port
    Channel-group listing:
    -----------------------
    Group: 1
    ----------
    Ports in the group:
    -------------------
    Port: Fa0/1
    ------------
    Port state = Up Mstr In-Bndl
    Channel group = 1 Mode = Desirable-Sl Gcchange = 0
    Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
    Port index = 0 Load = 0x00 Protocol = PAgP
    Flags: S - Device is sending Slow hello. C - Device is in Consistent state.
    A - Device is in Auto mode. P - Device learns on physical port.
    d - PAgP is down.
    Timers: H - Hello timer is running. Q - Quit timer is running.
    S - Switching timer is running. I - Interface timer is running.

    Local information:
    Hello Partner PAgP Learning Group
    Port Flags State Timers Interval Count Priority Method Ifindex
    Fa0/1 SC U6/S7 H 30s 1 128 Any 29

    Partner's information:

    Partner Partner Partner Partner Group
    Port Name Device ID Port Age Flags Cap.
    Fa0/1 Access 000d.bc33.2b00 Fa0/1 0s SC 10001
    Age of the port in the current state: 00d:00h:06m:04s
    Port: Fa0/2
    ------------
    Port state = Up Mstr In-Bndl
    Channel group = 1 Mode = Desirable-Sl Gcchange = 0
    Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
    Port index = 0 Load = 0x00 Protocol = PAgP

    Flags: S - Device is sending Slow hello. C - Device is in Consistent state.
    A - Device is in Auto mode. P - Device learns on physical port.
    d - PAgP is down.
    Timers: H - Hello timer is running. Q - Quit timer is running.
    S - Switching timer is running. I - Interface timer is running.

    Local information:
    Hello Partner PAgP Learning Group
    Port Flags State Timers Interval Count Priority Method Ifindex
    Fa0/2 SC U6/S7 H 30s 1 128 Any 29

    Partner's information:

    Partner Partner Partner Partner Group
    Port Name Device ID Port Age Flags Cap.
    Fa0/2 Access 000d.bc33.2b00 Fa0/2 2s SC 10001

    Age of the port in the current state: 00d:00h:32m:20s

    Port: Fa0/3
    ------------

    Port state = Up Mstr In-Bndl
    Channel group = 1 Mode = Desirable-Sl Gcchange = 0
    Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
    Port index = 0 Load = 0x00 Protocol = PAgP

    Flags: S - Device is sending Slow hello. C - Device is in Consistent state.
    A - Device is in Auto mode. P - Device learns on physical port.
    d - PAgP is down.
    Timers: H - Hello timer is running. Q - Quit timer is running.
    S - Switching timer is running. I - Interface timer is running.

    Local information:
    Hello Partner PAgP Learning Group
    Port Flags State Timers Interval Count Priority Method Ifindex
    Fa0/3 SC U6/S7 H 30s 1 128 Any 29

    Partner's information:

    Partner Partner Partner Partner Group
    Port Name Device ID Port Age Flags Cap.
    Fa0/3 Access 000d.bc33.2b00 Fa0/3 14s SC 10001

    Age of the port in the current state: 00d:00h:04m:19s

    Channel group = 1 Mode = Desirable-Sl Gcchange = 0
    Port-channel = Po1 GC = 0x00010001 Pseudo port-channel = Po1
    Port index = 0 Load = 0x00 Protocol = PAgP

    Flags: S - Device is sending Slow hello. C - Device is in Consistent state.
    A - Device is in Auto mode. P - Device learns on physical port.
    d - PAgP is down.
    Timers: H - Hello timer is running. Q - Quit timer is running.
    S - Switching timer is running. I - Interface timer is running.

    Local information:
    Hello Partner PAgP Learning Group
    Port Flags State Timers Interval Count Priority Method Ifindex
    Fa0/4 SC U6/S7 H 30s 1 128 Any 29

    Partner's information:

    Partner Partner Partner Partner Group
    Port Name Device ID Port Age Flags Cap.
    Fa0/4 Access 000d.bc33.2b00 Fa0/4 14s SC 10001

    Age of the port in the current state: 00d:00h:48m:29s
    Ta có thể sử dụng lênh show etherchannel summary để dể xem xét hơn.
    Core#show etherchannel summary
    Flags: D - down P - in port-channel
    I - stand-alone s - suspended
    H - Hot-standby (LACP only)
    R - Layer3 S - Layer2
    u - unsuitable for bundling
    U - in use f - failed to allocate aggregator
    d - default port

    Number of channel-groups in use: 1
    Number of aggregators: 1

    Group Port-channel Protocol Ports
    ------+-------------+-----------+-----------------------------------------------
    1 Po1(SU) PAgP Fa0/1(P) Fa0/2(P) Fa0/3(P)
    Fa0/4(P)

    Kiểm tra bằng Ethereal:
    Khi 4 port đều up



    Khi ta shut dow một cổng của group đó là fa0/2 và fa0/3 ta có kết quả sau



    Cấu hình LACP
    Đối với cấu hình này thì ta cũng sữ dụng 4 interface fa0/1- fa0/4 làm etherchannel, Ở đây chỉ xét đến 2 Switch Core và Switch Access. Show run để kiểm tra cấu hình
    Core
    !
    hostname Core
    !
    enable password cisco
    !
    ip subnet-zero
    !
    lacp system-priority 100
    !
    interface Port-channel1
    no ip address
    !
    interface FastEthernet0/1
    switchport trunk encapsulation dot1q
    switchport mode trunk
    no ip address
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/2
    switchport trunk encapsulation dot1q
    switchport mode trunk
    no ip address
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/3
    switchport trunk encapsulation dot1q
    switchport mode trunk
    no ip address
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/4
    switchport trunk encapsulation dot1q
    switchport mode trunk
    no ip address
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/5
    switchport mode access
    no ip address
    spanning-tree portfast
    !
    interface FastEthernet0/6
    no ip address
    !
    interface FastEthernet0/7
    no ip address
    !
    interface FastEthernet0/8
    no ip address
    !
    interface FastEthernet0/9
    no ip address
    interface FastEthernet0/10
    no ip address
    !
    interface FastEthernet0/11
    no ip address
    !
    interface FastEthernet0/12
    no ip address
    !
    interface FastEthernet0/13
    no ip address
    !
    interface FastEthernet0/14
    no ip address
    !
    interface FastEthernet0/15
    no ip address
    !
    interface FastEthernet0/16
    no ip address
    !
    interface FastEthernet0/17
    no ip address
    !
    interface FastEthernet0/18
    no ip address
    !
    interface FastEthernet0/19
    no ip address
    !
    interface FastEthernet0/20
    no ip address
    !
    interface FastEthernet0/21
    no ip address
    !
    interface FastEthernet0/22
    no ip address
    !
    interface FastEthernet0/23
    no ip address
    !
    interface FastEthernet0/24
    no ip address
    !
    interface GigabitEthernet0/1
    no ip address
    !
    interface GigabitEthernet0/2
    no ip address
    !
    interface Vlan1
    ip address 192.168.5.1 255.255.255.0
    define interface-range cuong FastEthernet0/1 - 4
    !
    ip classless
    ip http server
    !
    monitor session 1 source interface Po1
    monitor session 1 destination interface Fa0/5
    end

    Access
    !
    hostname Access
    !
    enable password cisco
    !
    ip subnet-zero
    !
    no ip domain-lookup
    !
    spanning-tree mode pvst
    spanning-tree extend system-id
    lacp system-priority 10
    !
    interface Port-channel1
    switchport trunk encapsulation dot1q
    switchport mode trunk
    !
    interface FastEthernet0/1
    switchport trunk encapsulation dot1q
    switchport mode trunk
    duplex full
    speed 100
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/2
    switchport trunk encapsulation dot1q
    switchport mode trunk
    duplex full
    speed 100
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/3
    switchport trunk encapsulation dot1q
    switchport mode trunk
    duplex full
    speed 100
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/4
    switchport trunk encapsulation dot1q
    switchport mode trunk
    duplex full
    speed 100
    channel-group 1 mode active
    channel-protocol lacp
    !
    interface FastEthernet0/5
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/6
    switchport mode dynamic desirable
    !
    interface FastEthernet0/7
    switchport mode dynamic desirable
    !
    interface FastEthernet0/8
    switchport mode dynamic desirable
    !
    interface FastEthernet0/9
    switchport mode dynamic desirable
    !
    interface FastEthernet0/10
    switchport mode dynamic desirable
    !
    interface FastEthernet0/11
    switchport mode dynamic desirable
    !
    interface FastEthernet0/12
    switchport mode dynamic desirable
    !
    interface FastEthernet0/13
    switchport mode dynamic desirable
    !
    interface FastEthernet0/14
    switchport mode dynamic desirable
    !
    interface FastEthernet0/15
    switchport mode dynamic desirable
    interface FastEthernet0/16
    switchport mode dynamic desirable
    !
    interface FastEthernet0/17
    switchport mode dynamic desirable
    !
    interface FastEthernet0/18
    switchport mode dynamic desirable
    !
    interface FastEthernet0/19
    switchport mode dynamic desirable
    !
    interface FastEthernet0/20
    switchport mode dynamic desirable
    !
    interface FastEthernet0/21
    switchport mode dynamic desirable
    !
    interface FastEthernet0/22
    switchport mode dynamic desirable
    !
    interface FastEthernet0/23
    switchport mode dynamic desirable
    !
    interface FastEthernet0/24
    switchport mode dynamic desirable
    !
    interface GigabitEthernet0/1
    switchport mode dynamic desirable
    !
    interface GigabitEthernet0/2
    switchport mode dynamic desirable
    !
    interface Vlan1
    ip address 192.168.5.2 255.255.255.0
    define interface-range cuong FastEthernet0/1 - 4
    !
    ip classless
    ip http server
    end
    Kiểm tra
    Lệnh show lacp neighbor:
    SW1#show lacp neighbor
    Flags: S - Device is sending Slow LACPDUs F - Device is sending Fast LACPDUs
    A - Device is in Active mode P - Device is in Passive mode
    Channel group 1 neighbors
    Partner's information:

    Partner Partner Partner
    Port System ID Port Number Age Flags
    Fa0/1 00010,000d.299a.7e00 0x0 29s SA
    LACP Partner Partner Partner
    Port Priority Oper Key Port State
    32768 0x1 0x3D
    Partner's information:
    Partner Partner Partner
    Port System ID Port Number Age Flags
    Fa0/2 00010,000d.299a.7e00 0x1 11s SA
    LACP Partner Partner Partner
    Port Priority Oper Key Port State
    32768 0x1 0x3D
    Partner's information:
    Partner Partner Partner
    Port System ID Port Number Age Flags
    Fa0/3 00010,000d.299a.7e00 0x2 27s SA
    LACP Partner Partner Partner
    Port Priority Oper Key Port State
    32768 0x1 0x3D
    Partner's information:
    Partner Partner Partner
    Port System ID Port Number Age Flags
    Fa0/4 00010,000d.299a.7e00 0x3 12s SA
    LACP Partner Partner Partner
    Port Priority Oper Key Port State
    32768 0x1 0x3D
    Kiểm tra trạng thái các port bằng show lacp internal hoặc show etherchannel detail

    SW1#show lacp internal
    Flags: S - Device is sending Slow LACPDUs F - Device is sending Fast LACPDUs
    A - Device is in Active mode P - Device is in Passive mode

    Channel group 1
    LACP port Admin Oper Port Port
    Port Flags State Priority Key Key Number State
    Fa0/1 SA bndl 32768 0x1 0x1 0x0 0x3D
    Fa0/2 SA bndl 32768 0x1 0x1 0x1 0x3D
    Fa0/3 SA bndl 32768 0x1 0x1 0x2 0x3D
    Fa0/4 SA bndl 32768 0x1 0x1 0x3 0x3D
    Kiểm tra sys priority bằng lệnh
    Sw2#show lacp sys-id
    150 ,000d.299a.7e00
    Bằng Ethereal thì tương tự như trong trường hợp PAGP
    Email : vnpro@vnpro.org
    ---------------------------------------------------------------------------------------------------------------
Trung Tâm Tin Học VnPro
149/1D Ung Văn Khiêm P25 Q.Bình thạnh TPHCM
Tel : (08) 35124257 (5 lines)
Fax: (08) 35124314

Home page: http://www.vnpro.vn
Support Forum: http://www.vnpro.org		 - Chuyên đào tạo quản trị mạng và hạ tầng Internet
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- Tư vấn thiết kế và hỗ trợ kỹ thuật hệ thống mạng

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