Centos7多网卡绑定bond快速实践

一、准备环境
VMware软件、centos7虚拟机

二、添加网卡
为虚拟机再添加两块网卡，查看网卡信息，可以看到有ens32、ens34、ens35三块网卡
ip addr

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    .NET 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: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:54:02:06 brd ff:ff:ff:ff:ff:ff
    inet 192.168.30.142/24 brd 192.168.30.255 scope global noprefixroute dynamic ens32
       valid_lft 1615sec preferred_lft 1615sec
    inet6 fe80::d089:c15:e69a:8ce4/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
3: ens34: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:54:02:1a brd ff:ff:ff:ff:ff:ff
    inet 192.168.30.143/24 brd 192.168.30.255 scope global noprefixroute dynamic ens34
       valid_lft 1765sec preferred_lft 1765sec
    inet6 fe80::a4af:b843:9032:9dd3/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
4: ens35: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:54:02:10 brd ff:ff:ff:ff:ff:ff
    inet 192.168.30.141/24 brd 192.168.30.255 scope global noprefixroute dynamic ens35
       valid_lft 1765sec preferred_lft 1765sec
    inet6 fe80::b7cf:76d7:23aa:63c2/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

查看网卡配置文件，可以看到添加网卡后，并没有生成对应的网卡文件
ls
/etc/sysconfig/network-scripts/ifcfg*

/etc/sysconfig/network-scripts/ifcfg-ens32  /etc/sysconfig/network-scripts/ifcfg-lo

可以为网卡生成配置文件，但在本文中不需要这样做

nmcli connection add type ethernet con-name ens34 ifname ens34 autoconnect yes
nmcli connection add type ethernet con-name ens35 ifname ens35 autoconnect yes

再次查看网卡配置文件，生成成功
ls
/etc/sysconfig/network-scripts/ifcfg*

/etc/sysconfig/network-scripts/ifcfg-ens32  /etc/sysconfig/network-scripts/ifcfg-ens35
/etc/sysconfig/network-scripts/ifcfg-ens34  /etc/sysconfig/network-scripts/ifcfg-lo

三，选定网卡绑定模式
多网卡一共有7种bond模式，这里直接选用mode=6 (balance-alb) Adaptive load balancing（适配器适应性负载均衡），该模式不需要交换机支持

四、开始配置
1、加载bonding模块，并设置开机启动

[root@localhost ~]# lsmod | grep bonding
[root@localhost ~]# modprobe bonding
[root@localhost ~]# lsmod | grep bonding
bonding               152979  0

启用rc.local开机启动项
chmod +x /etc/rc.d/rc.local
在文件中写入modprobe bonding

2、建立bond网口配置文件并进行配置

/etc/sysconfig/network-scripts/ifcfg-bond0

DEVICE=bond0
NAME=bond0
TYPE=Bond
BONDING_MASTER=yes
IPADDR=192.168.30.250
PREFIX=255.255.255.0
GATEWAY=192.168.30.2
DNS1=114.114.114.114
ONBOOT=yes
BOOTPROTO=none
BONDING_OPTS="mode=6  miimon=100"

3、修改三块网卡的配置
vi
/etc/sysconfig/network-scripts/ifcfg-ens32

DEVICE=ens32
ONBOOT=yes
BOOTPROTO=none
TYPE=Ethernet
MASTER=bond0
SLAVE=yes

vi /etc/sysconfig/network-scripts/ifcfg-ens34

DEVICE=ens34
ONBOOT=yes
BOOTPROTO=none
TYPE=Ethernet
MASTER=bond0
SLAVE=yes

vi /etc/sysconfig/network-scripts/ifcfg-ens35

DEVICE=ens35
ONBOOT=yes
BOOTPROTO=none
TYPE=Ethernet
MASTER=bond0
SLAVE=yes

4、重新加载网络配置
注意：这一步会断网！

nmcli connection reload && systemctl restart network.service

使用新IP链接ssh

五、验证绑定是否生效
cat /proc/net/bonding/bond0

Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: adaptive load balancing
Primary Slave: None
Currently Active Slave: ens32
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: ens32
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link FAIlure Count: 0
Permanent HW addr: 00:0c:29:54:02:06
Slave queue ID: 0

Slave Interface: ens34
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 00:0c:29:54:02:1a
Slave queue ID: 0

Slave Interface: ens35
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 0
Permanent HW addr: 00:0c:29:54:02:10
Slave queue ID: 0

查看网卡状态
ip addr

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    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: ens32: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master bond0 state UP group default qlen 1000
    link/ether 00:0c:29:54:02:06 brd ff:ff:ff:ff:ff:ff
3: ens34: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master bond0 state UP group default qlen 1000
    link/ether 00:0c:29:54:02:1a brd ff:ff:ff:ff:ff:ff
4: ens35: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master bond0 state UP group default qlen 1000
    link/ether 00:0c:29:54:02:10 brd ff:ff:ff:ff:ff:ff
5: bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 00:0c:29:54:02:06 brd ff:ff:ff:ff:ff:ff
    inet 192.168.30.250/24 brd 192.168.30.255 scope global bond0
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe54:206/64 scope link
       valid_lft forever preferred_lft forever

查看接口带宽，带宽为3G
ethtool bond0

Settings for bond0:
        Supported ports: [ ]
        Supported link modes:   Not reported
        Supported pause frame use: No
        Supports auto-negotiation: No
        Supported FEC modes: Not reported
        Advertised link modes:  Not reported
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Advertised FEC modes: Not reported
        Speed: 3000Mb/s
        Duplex: Full
        Port: Other
        PHYAD: 0
        Transceiver: internal
        Auto-negotiation: off
        Link detected: yes

连续ping测试，并禁用第一个网卡，此时会丢一个包，网络依然正常运行

来自 192.168.30.250 的回复: 字节=32 时间<1ms TTL=64
来自 192.168.30.250 的回复: 字节=32 时间<1ms TTL=64
来自 192.168.30.250 的回复: 字节=32 时间=1ms TTL=64
请求超时。
来自 192.168.30.250 的回复: 字节=32 时间=1ms TTL=64
来自 192.168.30.250 的回复: 字节=32 时间<1ms TTL=64