1. 簡要
雙網卡綁定技術在centos7中使用了teaming技術，而在rhel6/centos7中使用的是bonding技術，
在centos7中雙網卡綁定既能使用teaming也可以使用bonding，這裏推薦使用teaming技術，方便與查看和監控。
2. 原理
這裏介紹兩種最常見的雙網卡綁定模式：
（1） roundrobin - 輪詢模式
所有鏈路處於負載均衡狀態，這種模式的特點增加了帶寬，同時支持容錯能力。
（2） activebackup - 主備模式
一個網卡處於活動狀態，另一個處於備份狀態，所有流量都在主鏈路上處理，當活動網卡down掉時，啓用備份網卡。
3. 基礎環境
系統：centos7
在centos7中，關閉虛擬機添加網卡，再開啓虛擬機，系統是不會自動生成網卡的配置文件：
在centos7中要生成網卡配置文件的方法很簡單，使用如下命令：
# 查看物理網卡信息 [root@localhost ~]# nmcli dev DEVICE TYPE STATE CONNECTION eno16777736 ethernet connected eno16777736 eno33554984 ethernet connected Wired connection 1 eno50332208 ethernet connected Wired connection 2 lo loopback unmanaged --
上面的信息可以看到，一共有四張網卡，其中lo是本地迴環網卡，另外三張爲物理網卡。
# 查看網卡連接信息 [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE Wired connection 2 9a1314bf-d273-406a-930a-dc4160dee4ec 802-3-ethernet eno50332208 Wired connection 1 47eef4a3-7fa4-4a73-83ef-1485bda9b950 802-3-ethernet eno33554984 eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736
上面的信息可以查看到一共有3個連接，其中兩個有線連接，表示沒有設置過的網卡連接，還有一個enoxx連接。接下來要修改兩個有線連接的命名方法，並生成網卡配置文件：
# 首先，刪除兩個無用的有線連接 [root@localhost ~]# nmcli con del 9a1314bf-d273-406a-930a-dc4160dee4ec Connection 'Wired connection 2' (9a1314bf-d273-406a-930a-dc4160dee4ec) successfully deleted. [root@localhost ~]# nmcli con del 47eef4a3-7fa4-4a73-83ef-1485bda9b950 Connection 'Wired connection 1' (47eef4a3-7fa4-4a73-83ef-1485bda9b950) successfully deleted.
# 再次創建新的連接並生成配置文件 [root@localhost ~]# nmcli conn add type ethernet con-name eno50332208 ifname eno50332208 Connection 'eno50332208' (eea2a115-63f8-4f33-be84-12559f02542c) successfully added. [root@localhost ~]# nmcli conn add type ethernet con-name eno33554984 ifname eno33554984 Connection 'eno33554984' (32d2389e-4e82-4419-9d18-5aff8f0be003) successfully added.
# 最後，查看下 [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 eno33554984 32d2389e-4e82-4419-9d18-5aff8f0be003 802-3-ethernet eno33554984 eno50332208 eea2a115-63f8-4f33-be84-12559f02542c 802-3-ethernet eno50332208 [root@localhost ~]# ll /etc/sysconfig/network-scripts/ifcfg-eno* -rw-r--r--. 1 root root 394 Nov 26 05:59 /etc/sysconfig/network-scripts/ifcfg-eno16777736-rw-r--r--. 1 root root 288 Dec 26 08:44 /etc/sysconfig/network-scripts/ifcfg-eno33554984-rw-r--r--. 1 root root 288 Dec 26 08:44 /etc/sysconfig/network-scripts/ifcfg-eno50332208
網絡連接和配置文件都成功生成了。 接下來通過eno33554984 和 eno50332208 使用teaming模式進行雙網卡綁定
4. roundrobin模式：
roundrobin模式也稱爲輪詢模式，它 基於每一個包 ，當某一臺服務器的兩張網卡設置爲roundrobin模式teaming，此時服務器發出的數據包，就會在兩個物理
網卡上進行輪詢，即第一個數據包走一張網卡，第二個數據包走第二張網卡，依次輪詢。
注意：
（1）roundrobin具有容錯性，當一張網卡down掉，數據包依然發送成功。
（2）在使用roundrobin模式必須要在交換機上做以太通道，不然會出現網絡無法連通。
實際操作：
# 使用nmcli命令操作，創建team接口team0，同時設置teaming模式爲roundrobin
[root@localhost ~]# nmcli con add type team con-name team0 ifname team0 config '{"runner":{"name": "roundrobin"}}'Connection 'team0' (9dc48bd6-54b9-48db-b7dd-ecf34ae9196f) successfully added.# 給接口team0設置ip地址 [root@localhost ~]# nmcli con modify team0 ipv4.address '10.0.0.2/24' ipv4.gateway '10.0.0.1' # 設置爲手動模式，取消DHCP [root@localhost ~]# nmcli con modify team0 ipv4.method manual
# 將兩張物理網卡加入到team中 [root@localhost ~]# nmcli con add type team-slave con-name team0-port1 ifname eno33554984 master team0 Connection 'team0-port1' (22d3640e-f5c8-499c-b0dd-913c8970d800) successfully added. [root@localhost ~]# nmcli con add type team-slave con-name team0-port2 ifname eno50332208 master team0 Connection 'team0-port2' (12660d2a-0e1f-41e6-96b2-53de4fc6b78c) successfully added. [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE team0-port2 12660d2a-0e1f-41e6-96b2-53de4fc6b78c 802-3-ethernet -- eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 team0-port1 22d3640e-f5c8-499c-b0dd-913c8970d800 802-3-ethernet -- team0 9dc48bd6-54b9-48db-b7dd-ecf34ae9196f team team0 eno33554984 32d2389e-4e82-4419-9d18-5aff8f0be003 802-3-ethernet eno33554984 eno50332208 eea2a115-63f8-4f33-be84-12559f02542c 802-3-ethernet eno50332208
# 查看team0的狀態 [root@localhost ~]# teamdctl team0 st setup: runner: roundrobin
4.1 roundrobin問題排查
第一次查看出現的是這樣的結果，檢查下配置：
# 通過直接查看網卡發現team0並沒有啓動 [root@localhost ~]# ip a | grep team05: team0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN # 使用ifup 啓動team0並沒有成功，繼續排查 [root@localhost ~]# ifup team0 [root@localhost ~]# ip a | grep team05: team0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN
直接sysetmctl restart network 也沒有成功。
# 發現team0-port1 team0-port2沒有添加成功物理網卡，怎麼回事呢？ [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE team0-port2 ec96c1e1-d268-4ba1-a2f9-0133a9f02655 802-3-ethernet -- eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 team0-port1 22d3640e-f5c8-499c-b0dd-913c8970d800 802-3-ethernet -- team0 9dc48bd6-54b9-48db-b7dd-ecf34ae9196f team team0 eno33554984 32d2389e-4e82-4419-9d18-5aff8f0be003 802-3-ethernet eno33554984 eno50332208 eea2a115-63f8-4f33-be84-12559f02542c 802-3-ethernet eno50332208
# 刪除掉 [root@localhost ~]# nmcli con del team0-port1 Connection 'team0-port1' (22d3640e-f5c8-499c-b0dd-913c8970d800) successfully deleted. [root@localhost ~]# nmcli con del team0-port2 Connection 'team0-port2' (ec96c1e1-d268-4ba1-a2f9-0133a9f02655) successfully deleted. # 刪除兩張物理網卡的連接 [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 team0 9dc48bd6-54b9-48db-b7dd-ecf34ae9196f team team0 eno33554984 32d2389e-4e82-4419-9d18-5aff8f0be003 802-3-ethernet eno33554984 eno50332208 eea2a115-63f8-4f33-be84-12559f02542c 802-3-ethernet eno50332208 [root@localhost ~]# nmcli con del eno33554984 eno50332208 Connection 'eno33554984' (32d2389e-4e82-4419-9d18-5aff8f0be003) successfully deleted. Connection 'eno50332208' (eea2a115-63f8-4f33-be84-12559f02542c) successfully deleted. # 刪除成功 [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 team0 9dc48bd6-54b9-48db-b7dd-ecf34ae9196f team team0
# 再次將兩張物理網卡添加到team [root@localhost ~]# nmcli con add type team-slave con-name team0-port1 ifname eno33554984 master team0 Connection 'team0-port1' (0331ea43-95c0-4106-b388-8484d4c3940d) successfully added. [root@localhost ~]# nmcli con add type team-slave con-name team0-port2 ifname eno50332208 master team0 Connection 'team0-port2' (880f2146-fe93-42dd-8d28-7d0dd50b4011) successfully added. [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE team0-port1 0331ea43-95c0-4106-b388-8484d4c3940d 802-3-ethernet eno33554984 eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 team0 9dc48bd6-54b9-48db-b7dd-ecf34ae9196f team team0 team0-port2 880f2146-fe93-42dd-8d28-7d0dd50b4011 802-3-ethernet eno50332208
現在成功將兩張物理網卡綁定到了team組中
# 現在查看team0的狀態就出現了，模式是：roundrobin [root@localhost ~]# teamdctl team0 st setup: runner: roundrobin ports: eno33554984 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0 eno50332208 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0
這樣，team模式的roundrobin搭建成功。
總結：
在做鏈路聚合的時候，所要使用到的物理網卡不能獨立存在連接，也就是在nmcli con sh查看時，不能獨立存在，否則就無法綁定到team模式中。
4.2 測試
因爲這裏是虛擬機環境，只能通過down掉網卡進行查看。
[root@localhost ~]# teamdctl team0 st setup: runner: roundrobin ports: eno33554984 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0 eno50332208 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0
兩張網卡同時在線，現在down掉其中一張網卡，
[root@localhost ~]# nmcli con del team0-port1 Connection 'team0-port1' (0331ea43-95c0-4106-b388-8484d4c3940d) successfully deleted. [root@localhost ~]# nmcli con shNAME UUID TYPE DEVICE eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 team0 9dc48bd6-54b9-48db-b7dd-ecf34ae9196f team team0 team0-port2 880f2146-fe93-42dd-8d28-7d0dd50b4011 802-3-ethernet eno50332208 [root@localhost ~]# teamdctl team0 st setup: runner: roundrobin ports: eno50332208 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0
這樣就發現eno33554984網卡已經down掉了。
[root@localhost ~]# nmcli con add type team-slave con-name team0-port1 ifname eno33554984 master team0 Connection 'team0-port1' (59acd6bf-affc-4994-a050-83c45816859a) successfully added. [root@localhost ~]# [root@localhost ~]# teamdctl team0 st setup: runner: roundrobin ports: eno33554984 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0 eno50332208 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0
虛擬機環境就這樣測試了吧，至於生產環境就直接拔網線，ping測試。
資料有說linux下roundrobin具有容錯的效果，爲了測試是否有容錯的效果，虛擬機做了下更改來驗證：
這一次網卡全部改成橋接模式，爲了更好的測試是否具有容錯性。
roundrobin已經配置完畢。接下來我們down掉一張網卡檢查是否具有容錯性。
通過虛擬機測試，容錯性是存在的。
5. 雙網卡綁定activebackup的實現
[root@localhost ~]# nmcli con sh NAME UUID TYPE DEVICE team0-port2 2a1aa534-e021-4452-bb0a-2002dabcbc08 802-3-ethernet eno50332208 team0-port1 9a10c9ef-ee9c-4151-9a47-59b4668e8934 802-3-ethernet -- eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 team0 c2278f3f-5c6b-4e1d-b925-514d3c3832b6 team team0 [root@localhost ~]# nmcli con del team0 team0-port1 team0-port2 Connection 'team0' (c2278f3f-5c6b-4e1d-b925-514d3c3832b6) successfully deleted. Connection 'team0-port1' (9a10c9ef-ee9c-4151-9a47-59b4668e8934) successfully deleted. Connection 'team0-port2' (2a1aa534-e021-4452-bb0a-2002dabcbc08) successfully deleted. [root@localhost ~]# nmcli con sh NAME UUID TYPE DEVICE eno16777736 51d00668-2cf5-41da-ad8d-5019d62e98ad 802-3-ethernet eno16777736 # 以上操作就刪除了roundrobin模式，恢復到初始狀態。
# 添加邏輯網卡team0，並啓用activebackup模式
[root@localhost ~]# nmcli con add type team con-name team0 ifname team0 config '{"runner":{"name":"activebackup"}}'Connection 'team0' (f0794e59-419d-4c2a-96b9-464610b6321a) successfully added.
# 綁定ip
[root@localhost ~]# nmcli con modify team0 ipv4.address 192.168.118.122/24 ipv4.gateway 192.168.118.1[root@localhost ~]# nmcli con modify team0 ipv4.method manual
# 添加物理網卡到activebackup模式
[root@localhost ~]# nmcli con add type team-slave con-name team0-port1 ifname eno33554984 master team0
Connection 'team0-port1' (52656904-6e85-4a04-98b4-2b19773fa290) successfully added.
[root@localhost ~]# nmcli con add type team-slave con-name team0-port2 ifname eno50332208 master team0
Connection 'team0-port2' (44d96e3a-014a-481f-9122-4ca2d3be9f7a) successfully added.
[root@localhost ~]# teamdctl team0 st setup: runner: activebackup ports: eno33554984 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0 eno50332208 link watches: link summary: up instance[link_watch_0]: name: ethtool link: up down count: 0runner: active port: eno33554984
成功，處於活動中的網卡爲 eno33554984
5.1 測試
通過down掉活動網卡測試網絡是否仍然處於連通狀態
測試成功。
注意： 在做網卡綁定的時候，如果發現物理網卡總是無法綁定到team0，請檢查該物理網卡是否處於up狀態。