centos8.2 创建链路聚合mode4的 也就是bond4

网卡数据链路层负载均衡是使用mode4，且可以实现物理链路间互备，提供给用户的是一个逻辑上的链路，该逻辑链路的有效网络带宽为全部物理链路带宽之和。

Bonding mode4的一些特性：

最多支持绑定8个主机的网卡端口；

LACP控制协议数据包每秒发送一次，检测主机网卡是否存活的检测包每30秒（fast）或每秒（slow）发送一次；

LACP mode：active或passive，默认为passive模式，即只有当探测到有支持LACP功能的设备时自己才启用LACP功能；

对Bonding mode4的理解可以参考下面的链接。

1、Bonding的模式一共有7种

#defineBOND_MODE_ROUNDROBIN       0   （balance-rr模式）网卡的负载均衡模式

#defineBOND_MODE_ACTIVEBACKUP     1   （active-backup模式）网卡的容错模式

#defineBOND_MODE_XOR              2   （balance-xor模式）需要交换机支持

#defineBOND_MODE_BROADCAST        3    （broadcast模式）

#defineBOND_MODE_8023AD           4   （IEEE 802.3ad动态链路聚合模式）需要交换机支持

#defineBOND_MODE_TLB              5   自适应传输负载均衡模式

#defineBOND_MODE_ALB              6   网卡虚拟化方式

 bonding模块的所有工作模式可以分为两类：多主型工作模式和主备型工作模式，balance-rr 和broadcast属于多主型工作模式而active-backup属于主备型工作模式。（balance-xor、自适应传输负载均衡模式（balance-tlb）和自适应负载均衡模式（balance-alb）也属于多主型工作模式，IEEE 802.3ad动态链路聚合模式（802.3ad）属于主备型工作模式。

 2、加载并查看bonding模块

可以使用modinfo bonding 命令查看bonding模块的信息，默认情况下bonding模块没有被加载

可以以root用户登录，输入如下的命令进行开启加载bonding模块

modprobe  bonding    

modinfo bonding

lsmod | grep 'bonding'

3、修改网卡配置文件

创建/etc/sysconfig/network-scripts/ifcfg-bond0文件，加入如下内容：

DEVICE=bond0

NAME=bond0

TYPE=Bond

BONDING_MASTER=yes

IPADDR=10.10.7.2

PREFIX=24

GATEWAY=192.168.120.1

ONBOOT=yes

BOOTPROTO=static

BONDING_OPTS="mode=4 miimon=100 lacp_rate=1"

注：mode=4，设置为链路负载均衡模式；miimon=100，监控网线链路故障的时间间隔(毫秒)；lacp_rate=1，检测主机网卡是否存活的检测包每30秒（fast）或每秒（slow）发送一次。

修改/etc/sysconfig/network-scripts/ifcfg-ens27f0文件：

DEVICE=ens27f0

TYPE=Ethernet

BOOTPROTO=static

NAME=ens27f0

ONBOOT=yes

MASTER=bond0

SLAVE=yes

修改/etc/sysconfig/network-scripts/ifcfg-ens27f1文件：

DEVICE=ens27f1

TYPE=Ethernet

BOOTPROTO=static

NAME=em2

ONBOOT=yes

MASTER=bond0

SLAVE=yes

在主机上确认配置结果方法： 

#cat /proc/net/bonding/bond0

#ethtool  bond0

注意查看Speed是否是2000Mb/s

[root@localhost ~]# 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: 2000Mb/s
Duplex: Full
Port: Other
PHYAD: 0
Transceiver: internal
Auto-negotiation: off
Link detected: yes
[root@localhost ~]# cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: IEEE 802.3ad Dynamic link aggregation
Transmit Hash Policy: layer2 (0)
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 0
Down Delay (ms): 0
Peer Notification Delay (ms): 0

802.3ad info
LACP rate: fast
Min links: 0
Aggregator selection policy (ad_select): stable
System priority: 65535
System MAC address: b4:05:5d:fc:66:7f
Active Aggregator Info:
Aggregator ID: 1
Number of ports: 2
Actor Key: 9
Partner Key: 4
Partner Mac Address: 80:61:6c:c8:38:90

Slave Interface: ens27f0
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 1
Permanent HW addr: b4:05:5d:fc:66:7f
Slave queue ID: 0
Aggregator ID: 1
Actor Churn State: none
Partner Churn State: none
Actor Churned Count: 0
Partner Churned Count: 0
details actor lacp pdu:
system priority: 65535
system mac address: b4:05:5d:fc:66:7f
port key: 9
port priority: 255
port number: 1
port state: 63
details partner lacp pdu:
system priority: 32768
system mac address: 80:61:6c:c8:38:90
oper key: 4
port priority: 32768
port number: 7
port state: 61

Slave Interface: ens27f1
MII Status: up
Speed: 1000 Mbps
Duplex: full
Link Failure Count: 1
Permanent HW addr: b4:05:5d:fc:66:80
Slave queue ID: 0
Aggregator ID: 1
Actor Churn State: none
Partner Churn State: none
Actor Churned Count: 0
Partner Churned Count: 0
details actor lacp pdu:
system priority: 65535
system mac address: b4:05:5d:fc:66:7f
port key: 9
port priority: 255
port number: 2
port state: 63
details partner lacp pdu:
system priority: 32768
system mac address: 80:61:6c:c8:38:90
oper key: 4
port priority: 32768
port number: 8
port state: 61
[root@localhost ~]#

系统服务NetworkManager 没有关闭，网上好多说要关闭，我这边测CENTOS8.没有影响