CentOS7双网卡绑定
<h2>（一）简述</h2>
<h3>1.teaming技术</h3>
<p>双网卡绑定技术在centos7中使用了teaming技术，而在rhel6/centos7中使用的是bonding技术，
在centos7中双网卡绑定既能使用teaming也可以使用bonding，这里推荐使用teaming技术，方便与查看和监控。</p>
<h3>2.原理</h3>
<pre><code>这里介绍两种最常见的双网卡绑定模式：
（1） roundrobin - 轮询模式
所有链路处于负载均衡状态，这种模式的特点增加了带宽，同时支持容错能力。
（2） activebackup - 主备模式
一个网卡处于活动状态，另一个处于备份状态，所有流量都在主链路上处理，当活动网卡down掉时，启用备份网卡。</code></pre>
<h3>3.查看服务器的相关信息</h3>
<p>安装前state为connected</p>
<pre><code class="language-bash">[root@localhost ~]# nmcli dev
DEVICE TYPE STATE CONNECTION
em1 ethernet connected --
em2 ethernet connected --
em3 ethernet unavailable --
em4 ethernet unavailable --
lo loopback unmanaged -- </code></pre>
<pre><code class="language-bash">[root@localhost ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: em1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master team0 state UP qlen 1000
link/ether 36:3c:c4:19:d0:ef brd ff:ff:ff:ff:ff:ff
3: em2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master team0 state UP qlen 1000
link/ether 36:3c:c4:19:d0:ef brd ff:ff:ff:ff:ff:ff
4: em3: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN qlen 1000
link/ether 24:6e:96:a2:dd:ae brd ff:ff:ff:ff:ff:ff
5: em4: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN qlen 1000
link/ether 24:6e:96:a2:dd:af brd ff:ff:ff:ff:ff:ff
18: team0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
link/ether 36:3c:c4:19:d0:ef brd ff:ff:ff:ff:ff:ff
inet 10.128.105.156/24 brd 10.128.105.255 scope global team0
valid_lft forever preferred_lft forever
inet6 fe80::718:e575:f031:47d4/64 scope link
valid_lft forever preferred_lft forever</code></pre>
<p>其中state UP 为网卡有网线或启用的网口，有上边的参数可知，em1和em2有网线接口，其他的网口没有。lo为本地回环网卡</p>
<h2>（二）Roundrobin（轮询）安装步骤</h2>
<h3>1.查看网卡的连接信息：nmcli con sh</h3>
<pre><code class="language-bash">[root@localhost ~]# nmcli con sh
NAME UUID TYPE DEVICE
em1 4c8a8aee-327b-4f29-9ec4-ea2b2551420b 802-3-ethernet --
em2 62bde3ef-9f40-42aa-9b3a-4fe8b1aabf42 802-3-ethernet --
em3 56ef9d05-3a5d-4cd6-af5b-3d39adce619f 802-3-ethernet --
em4 761f7809-d10c-4e3b-bc06-c0906ca55d1c 802-3-ethernet -- </code></pre>
<h3>2.删除无用的网卡：nmcli con del em3</h3>
<p>此步，我未操作。</p>
<pre><code class="language-bash">[root@localhost ~]# nmcli con del em3
Connection 'em3' (56ef9d05-3a5d-4cd6-af5b-3d39adce619f) successfully deleted.
[root@localhost ~]# nmcli con sh
NAME UUID TYPE DEVICE
em1 4c8a8aee-327b-4f29-9ec4-ea2b2551420b 802-3-ethernet --
em2 62bde3ef-9f40-42aa-9b3a-4fe8b1aabf42 802-3-ethernet --
em4 761f7809-d10c-4e3b-bc06-c0906ca55d1c 802-3-ethernet -- </code></pre>
<h3>3.使用nmcli命令操作，创建team接口team0，同时设置teaming模式为roundrobin</h3>
<pre><code class="language-bash">[root@localhost ~]# nmcli con add type team con-name team0 ifname team0 config '{"runner":{"name": "roundrobin"}}'</code></pre>
<pre><code class="language-bash">[root@localhost ~]# nmcli con sh
NAME UUID TYPE DEVICE
team0 5a1976d7-2c91-456e-8dda-0b12c6ef0c04 team team0
em1 4c8a8aee-327b-4f29-9ec4-ea2b2551420b 802-3-ethernet --
em2 62bde3ef-9f40-42aa-9b3a-4fe8b1aabf42 802-3-ethernet --
em4 761f7809-d10c-4e3b-bc06-c0906ca55d1c 802-3-ethernet -- </code></pre>
<h3>4.给接口team0设置ip地址和网关，</h3>
<pre><code class="language-bash">[root@localhost ~]# nmcli con modify team0 ipv4.address '10.128.105.157/24' ipv4.gateway '10.128.105.254' </code></pre>
<h3>设置为手动模式，并取消手动模式</h3>
<pre><code class="language-bash">[root@localhost ~]# nmcli con modify team0 ipv4.method manual</code></pre>
<h3>5.将两张物理网卡添加到team</h3>
<pre><code class="language-bash">[root@localhost ~]# nmcli con add type team-slave con-name team0-port2 ifname em1 master team0
Connection 'team0-port2' (e01c37f5-b3a1-4e6d-96ab-a6e676ad3c32) successfully added.
[root@localhost ~]# nmcli con add type team-slave con-name team0-port2 ifname em2 master team0
Connection 'team0-port2' (8b13a9de-d64c-44fc-a86d-ea45d2f511cf) successfully added.</code></pre>
<pre><code class="language-bash">
[root@localhost ~]# nmcli con sh
NAME UUID TYPE DEVICE
team0 64b123d5-189d-43b0-a850-77d47c0da86c team team0
team0-port1 24181898-bffe-4ae1-90e8-f47da64b5512 802-3-ethernet em1
team0-port2 8b13a9de-d64c-44fc-a86d-ea45d2f511cf 802-3-ethernet em2
em1 4c8a8aee-327b-4f29-9ec4-ea2b2551420b 802-3-ethernet --
em2 62bde3ef-9f40-42aa-9b3a-4fe8b1aabf42 802-3-ethernet --
em4 761f7809-d10c-4e3b-bc06-c0906ca55d1c 802-3-ethernet -- </code></pre>
<h3>6.使用ifup team0 启用team0网卡，然后重启网络服务。</h3>
<p>ifup team0 如果启不来，可以reboot。
systemctl restart network 会报错，原因未查明。</p>
<pre><code class="language-bash">[root@localhost ~]# ifup team0
[root@localhost ~]# /etc/init.d/network restart
Restarting network (via systemctl): [ OK ]
[root@localhost ~]# ip a |grep team0
2: em1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master team0 state UP qlen 1000
10: team0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
inet 10.128.105.157/24 brd 10.128.105.255 scope global team0</code></pre>
<h3>7.现在查看team0的状态模式是否是roundrobin。teamdctl team0 st</h3>
<pre><code class="language-bash">[root@localhost ~]# teamdctl team0 st
setup:
runner: roundrobin
ports:
em1
link watches:
link summary: up
instance[link_watch_0]:
name: ethtool
link: up
down count: 0
em2
link watches:
link summary: up
instance[link_watch_0]:
name: ethtool
link: up</code></pre>
<p>这样，team模式的roundrobin搭建成功。</p>
<h3>8.测试是否正常工作</h3>
<h4>8.1.首先把em1网卡禁用，用其他的服务器ping看是否断。</h4>
<pre><code class="language-bash">[root@localhost etc]# ifdown em1
Device 'em1' successfully disconnected.
[root@localhost etc]# nmcli con sh
NAME UUID TYPE DEVICE
team0 64b123d5-189d-43b0-a850-77d47c0da86c team team0
team0-port2 8b13a9de-d64c-44fc-a86d-ea45d2f511cf 802-3-ethernet em2
em1 4c8a8aee-327b-4f29-9ec4-ea2b2551420b 802-3-ethernet --
em2 62bde3ef-9f40-42aa-9b3a-4fe8b1aabf42 802-3-ethernet --
em4 761f7809-d10c-4e3b-bc06-c0906ca55d1c 802-3-ethernet --
team0-port1 24181898-bffe-4ae1-90e8-f47da64b5512 802-3-ethernet --
[root@localhost ~]# teamdctl team0 st
setup:
runner: roundrobin
ports:
em2
link watches:
link summary: up
instance[link_watch_0]:
name: ethtool
link: up
down count: 0</code></pre>
<p><img src="https://www.showdoc.cc/server/api/common/visitfile/sign/43a0e1f300f6ff214d1dc7e5bad1a0c3?showdoc=.jpg" alt="" /></p>
<p><img src="https://www.showdoc.cc/server/api/common/visitfile/sign/de5b190f46e46258ae717db6cbf4c310?showdoc=.jpg" alt="" />
从上图看出实在正常的。</p>
<h4>8.2.把网卡em1启用，em2禁用查看下下</h4>
<pre><code class="language-bash">[root@localhost etc]# ifup em1
[root@localhost etc]# nmcli con sh
NAME UUID TYPE DEVICE
team0 64b123d5-189d-43b0-a850-77d47c0da86c team team0
team0-port1 24181898-bffe-4ae1-90e8-f47da64b5512 802-3-ethernet em1
team0-port2 8b13a9de-d64c-44fc-a86d-ea45d2f511cf 802-3-ethernet em2
em1 4c8a8aee-327b-4f29-9ec4-ea2b2551420b 802-3-ethernet --
em2 62bde3ef-9f40-42aa-9b3a-4fe8b1aabf42 802-3-ethernet --
em4 761f7809-d10c-4e3b-bc06-c0906ca55d1c 802-3-ethernet --
[root@localhost etc]# ifdown em2
Device 'em2' successfully disconnected.
[root@localhost etc]# nmcli con sh
NAME UUID TYPE DEVICE
team0 64b123d5-189d-43b0-a850-77d47c0da86c team team0
team0-port1 24181898-bffe-4ae1-90e8-f47da64b5512 802-3-ethernet em1
em1 4c8a8aee-327b-4f29-9ec4-ea2b2551420b 802-3-ethernet --
em2 62bde3ef-9f40-42aa-9b3a-4fe8b1aabf42 802-3-ethernet --
em4 761f7809-d10c-4e3b-bc06-c0906ca55d1c 802-3-ethernet --
team0-port2 8b13a9de-d64c-44fc-a86d-ea45d2f511cf 802-3-ethernet -- </code></pre>
<p>网卡流量em2没变，而em1变化了。
<img src="https://www.showdoc.cc/server/api/common/visitfile/sign/e9004857a9bb2ab1d5bcfc3bb12bcc7e?showdoc=.jpg" alt="" /></p>
<h2>（三）双网卡绑定activebackup的实现</h2>
<p>待续</p>
<p>来源：<a href="https://blog.51cto.com/liqingbiao/2089733">https://blog.51cto.com/liqingbiao/2089733</a></p>