第1部分 IRF簡書
1.什麼是IRF
硬件虛擬化IRF（智能彈性框架）帶來的優勢：組網簡化：如下圖所示，傳統的3層架構，核心交換機之間使用了以太捆綁，和接入層交換機運行STP，此時導致接入交換機之間只有部分處於轉發狀態（可以通過MSTP調整優化不同VLAN間的數據轉發）。在實施IRF之後2臺核心交換之間實施硬件虛擬化，被視爲一臺設備。這大大的簡化了網絡的複雜性。匯聚層的多個設備成爲了一個單一的邏輯設備，接入設備直接連接到這個虛擬設備。這種簡化後的組網不再需要使用MSTP、VRRP協議，簡化了網絡配置。同時依靠跨設備的鏈路聚合（需要特定設備支持），在成員出現故障時不再依賴MSTP、VRRP等協議的收斂，提高了可靠性
2.IRF的成員組成和接口類型
IRF堆疊中的成員設備分爲Master和Slave設備
成員設備上用於堆疊連接的物理接口稱之爲物理堆疊口
物理堆疊口需要和邏輯堆疊口綁定，邏輯堆疊口簡稱爲堆疊口
由多個物理堆疊口聚合的堆疊口成爲聚合堆疊口
3. IRF拓撲和拓撲發現
IRF堆疊物理拓撲：鍊形拓撲和環形拓撲
堆疊設備通過和直連的其他成員交互IRF Hello來收集整個堆疊的拓撲信息
拓撲收集完畢進入角色選舉過程
第2部分 IRF實施案例
2.1實施拓撲：
步驟1. 確定IRF設備角色，配置設備的IRF優先級和編號
[IRF2]irf member 1 renumber 2 //將IRF2(即SW2)的成員編號設置爲2，默認爲1
Renumbering the member ID may result in configuration change or loss. Continue?[Y/N]:y //對成員1中的背板重編號必須可能導致配置改變或者丟棄，是否繼續？是
[IRF2]save //切記保存配置
The current configuration will be written to the device. Are you sure? [Y/N]:y //確定保存
Please input the file name(*.cfg)[flash:/startup.cfg]
(To leave the existing filename unchanged, press the enter key): //使用默認的配置名稱，即start.cfg
Validating file. Please wait...
Saved the current configuration to mainboard device successfully.
[IRF2]quit
<IRF2>reboot //必須重啓設備
Start to check configuration with next startup configuration file, please wait.........DONE!
This command will reboot the device. Continue? [Y/N]:y //該命令將重啓設備，繼續麼？確認繼續
Now rebooting, please wait...
%Nov 25 22:02:11:207 2018 IRF2 DEV/5/SYSTEM_REBOOT: System is rebooting now.
！
！
[H3C]sysname IRF1
[IRF1]irf member 1 priority 32 //設置IRF1（SW1）的IRF優先級爲32，該值已經最大，保證IRF1設備成爲主設備（IRF2並未修改優先級，意味着它使用默認的優先級1）
[IRF1]int r te 1/0/50 to t 1/0/51
[IRF1-if-range]shu //把交換機互聯接口關閉，這是必須的一部
[IRF1-if-range]quit
[IRF1]irf-port 1/2 //設置IRF1的邏輯接口2
[IRF1-irf-port1/2]port g int te 1/0/50 //把物理接口加入邏輯接口
You must perform the following tasks for a successful IRF setup:
Save the configuration after completing IRF configuration.
Execute the "irf-port-configuration active" command to activate the IRF ports.
[IRF1-irf-port1/2]port g int te 1/0/51 //把物理接口加入邏輯接口
[IRF1-irf-port1/2]quit
[IRF1]int r te 1/0/50 to t 1/0/51
[IRF1-if-range]un sh //開啓物理接口步驟2. Slave設備加入物理成員接口
[IRF2]int r t 2/0/50 to t 2/0/51 //進入物理接口，注意之前已經“renember”了該設備的板卡號碼，所以接口爲10G接口的2/0/50和51接口
[IRF2-if-range]shu //IRF2設備重啓後關閉物理接口
[IRF2-if-range]quit
[IRF2]irf-port 2/1 //注意，特別推薦使用交叉互聯，請對比IRF1設備，否則可能造成堆疊失敗
[IRF2-irf-port2/1]port g int t 2/0/50 //把物理接口加入邏輯接口
You must perform the following tasks for a successful IRF setup:
Save the configuration after completing IRF configuration.
Execute the "irf-port-configuration active" command to activate the IRF ports.
[IRF2-irf-port2/1]port g int t 2/0/51 //把物理接口加入邏輯接口
[IRF2-irf-port2/1]quit
[IRF2]int r t 2/0/50 to t 2/0/51
[IRF2-if-range]un shu //開啓物理接口
%Nov 25 22:06:39:426 2018 IRF2 IFNET/3/PHY_UPDOWN: Physical state on the interface Ten-GigabitEthernet2/0/50 changed to up.
%Nov 25 22:06:39:474 2018 IRF2 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Ten-GigabitEthernet2/0/50 changed to up.
%Nov 25 22:06:39:495 2018 IRF2 LLDP/6/LLDP_CREATE_NEIGHBOR: Nearest bridge agent neighbor created on port Ten-GigabitEthernet2/0/50 (IfIndex 179), neighbor's chassis ID is 90c6-26d7-0100, port ID is Ten-GigabitEthernet1/0/50.
%Nov 25 22:06:39:648 2018 IRF2 IFNET/3/PHY_UPDOWN: Physical state on the interface Ten-GigabitEthernet2/0/51 changed to up.
[IRF2-if-range]%Nov 25 22:06:39:659 2018 IRF2 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Ten-GigabitEthernet2/0/51 changed to up.
%Nov 25 22:06:39:663 2018 IRF2 LLDP/6/LLDP_CREATE_NEIGHBOR: Nearest bridge agent neighbor created on port Ten-GigabitEthernet2/0/51 (IfIndex 180), neighbor's chassis ID is 90c6-26d7-0100, port ID is Ten-GigabitEthernet1/0/51.
[IRF2]save //保存配置
The current configuration will be written to the device. Are you sure? [Y/N]:y //確定保存配置
Please input the file name(*.cfg)[flash:/startup.cfg]
(To leave the existing filename unchanged, press the enter key):
flash:/startup.cfg exists, overwrite? [Y/N]:y //確定覆蓋已經存在的配置
Validating file. Please wait...
Saved the current configuration to mainboard device successfully.
<IRF1>save //保存配置
The current configuration will be written to the device. Are you sure? [Y/N]:y
Please input the file name(*.cfg)[flash:/startup.cfg]
(To leave the existing filename unchanged, press the enter key):
Validating file. Please wait...
Saved the current configuration to mainboard device successfully.<IRF1>
此時2臺設備的IRF已經配置完畢，但不激活IRF之前，IRF並不工作
步驟3.激活IRF配置
[IRF1]irf-port-configuration active //請在激活IRF配置前確保已經保存配置
[IRF1]%Nov 25 22:08:28:132 2018 IRF1 STM/6/STM_LINK_UP: IRF port 2 came up.
%Nov 25 22:08:45:321 2018 IRF1 STM/4/STM_MERGE: IRF merge occurred.
%Nov 25 22:08:47:660 2018 IRF1 IFNET/3/PHY_UPDOWN: Physical state on the interface Ten-GigabitEthernet1/0/51 changed to down.
%Nov 25 22:08:47:668 2018 IRF1 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Ten-GigabitEthernet1/0/51 changed to down.
%Nov 25 22:08:49:594 2018 IRF1 STM/3/STM_LINK_DOWN: IRF port 2 went down.
%Nov 25 22:08:49:606 2018 IRF1 IFNET/3/PHY_UPDOWN: Physical state on the interface Ten-GigabitEthernet1/0/50 changed to down.
%Nov 25 22:08:49:612 2018 IRF1 IFNET/5/LINK_UPDOWN: Line protocol state on the interface Ten-GigabitEthernet1/0/50 changed to down.
[IRF1]
[IRF2]%Nov 25 22:08:46:254 2018 IRF2 STM/6/STM_LINK_UP: IRF port 1 came up.//已經重啓
<IRF2>system-view //在IRF設備重啓後，暫時不會完成立即IRF，此時依舊顯示“IRF2”
System View: return to User View with Ctrl+Z.
[IRF2]int r t 2/0/50 to t 2/0/51
[IRF2-if-range]shu
[IRF2-if-range]und shu //重新關閉關閉，開啓物理接口。此時可能已經重啓 啓動後，如果成功那麼IRF2會變成IRF1
步驟4，IRF實施完畢後的驗證
[IRF1]display irf
MemberID Role Priority CPU-Mac Description
*+1 Master 32 90c6-26d7-0104 ---
2 Standby 1 90c6-2ea5-0204 ---
--------------------------------------------------
* indicates the device is the master.
+ indicates the device through which the user logs in.
The bridge MAC of the IRF is: 90c6-26d7-0100
Auto upgrade : yes
Mac persistent : 6 min
Domain ID : 0
[IRF1]dis irf link
Member 1
IRF Port Interface Status
1 disable --
2 Ten-GigabitEthernet1/0/50 UP
Ten-GigabitEthernet1/0/51 UP
Member 2
IRF Port Interface Status
1 Ten-GigabitEthernet2/0/50 UP
Ten-GigabitEthernet2/0/51 DOWN
2 disable --
[IRF1]dis irf topology
Topology Info
-------------------------------------------------------------------------
IRF-Port1 IRF-Port2
MemberID Link neighbor Link neighbor Belong To
1 DIS --- UP 2 90c6-26d7-0104
2 UP 1 DIS --- 90c6-26d7-0104
[IRF1]dis irf conf
MemberID NewID IRF-Port1 IRF-Port2
1 1 disable Ten-GigabitEthernet1/0/50
Ten-GigabitEthernet1/0/51
2 2 Ten-GigabitEthernet2/0/50 disable
Ten-GigabitEthernet2/0/51
chassis convert mode irf //切換到IRF工作模式（模擬器不支持）
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