linux 绑定网卡

在Linux系统中，网卡绑定是一种常见的网络优化技术，它可以将多个物理网卡绑定为一个逻辑网卡，从而提高网络的可靠性和负载均衡，本文将详细介绍Linux网卡绑定的过程和方法。

网卡绑定的原理

网卡绑定是将多个物理网卡绑定为一个逻辑网卡，这样可以实现以下功能：

1、提高网络的可靠性：当一个物理网卡出现故障时，其他绑定的网卡可以继续工作，保证网络的正常运行。

2、负载均衡：通过将数据流量分散到多个物理网卡上，可以提高网络的传输速度。

3、灵活配置：可以根据实际需求，随时增加或减少绑定的物理网卡。

网卡绑定的方法

在Linux系统中，可以使用bonding模块实现网卡绑定，bonding模块提供了多种绑定模式，如Roundrobin（轮询）、Activebackup（主备）等，下面介绍两种常用的绑定模式：

1、Roundrobin（轮询）模式

轮询模式是将所有绑定的物理网卡平均分配数据流量，每个网卡接收到的数据包按照顺序发送，这种模式下，所有网卡的负载基本相同，适用于负载均衡的场景。

2、Activebackup（主备）模式

主备模式是将一个物理网卡设置为主网卡，其他物理网卡设置为备份网卡，当主网卡正常工作时，数据包通过主网卡发送；当主网卡出现故障时，备份网卡接管数据包的发送，这种模式下，只有主网卡承担数据流量，适用于提高网络可靠性的场景。

网卡绑定的配置过程

以CentOS 7为例，介绍如何配置Roundrobin（轮询）模式的网卡绑定：

1、安装bonding模块：

yum install y epelrelease
yum install y bondingutils

2、查看当前系统中的网卡信息：

ip addr show

假设有两个物理网卡eth0和eth1，需要将它们绑定为一个逻辑网卡bond0。

3、编辑网络配置文件：

vi /etc/sysconfig/networkscripts/ifcfgbond0

添加以下内容：

DEVICE=bond0
BOOTPROTO=none
ONBOOT=yes
MASTER=bond0
SLAVE=eth0 eth1
USERCTL=no
BONDING_OPTS="mode=roundrobin miimon=100"

MASTER指定了主设备的名称，SLAVE指定了备份设备的名称，BONDING_OPTS指定了绑定模式和参数，这里使用的是Roundrobin（轮询）模式，参数miimon表示链路检测的时间间隔（单位：ms）。

4、编辑每个物理网卡的配置文件：

vi /etc/sysconfig/networkscripts/ifcfgeth0
vi /etc/sysconfig/networkscripts/ifcfgeth1

分别添加以下内容：

DEVICE=eth0
TYPE=Ethernet
BOOTPROTO=none
ONBOOT=yes
MASTER=bond0
SLAVE=yes
USERCTL=no

5、重启网络服务：

systemctl restart network.service

6、使用以下命令查看bond0的状态：

cat /proc/net/bonding/bond0 | grep "Mode" "Miimon" "Link" "Up" "Primary" "Aggregator" "Slave" "Master" "Downdelay" "Max retransmits" "Carrier" "Last transmit failed" "Activity" "Secs" "txqueuelen" "Interrupt" "rx_bytes" "tx_bytes" "rx_packets" "tx_packets" "rx_errors" "tx_errors" "rx_dropped" "tx_dropped" "tx_queuelen" "rx_queuelen" "rx_deferred" "tx_deferred" "carrier_transitions" "time_in_queue" "collisions" "tx_timeouts" "rx_length_errors" "rx_over_errors" "rx_crc_errors" "rx_frame_errors" "rx_fifo_errors" "rx_missed_errors" "tx_aborted_errors" "tx_carrier_errors" "tx_heartbeat_lost" "tx_window_errors" "rx_compressed" "tx_compressed" "multicast" "promiscuous" "mtu" "slaves misc state" "master state id invalidated time" "last heartbeat sent to master time" "last heartbeat received from master time" "max retransmits counter last updated time" "last transmission error time" "last receive error time" "last transmit error time" "last carrier transition time" "last activity time" "last slave link up time" "last slave link down time" "link status count since last change of state: up down inconsistent disco unco unsu faulty hard err disabled overload spoofing underrun backlog negotiation rrtt degraded prio flowcnt rxbcst rxmcst rxfh flts fwdchg carr intval aggrpad aggrrpadd aggrrpads aggrrpadl aggrrpause aggrrpwait aggrrphalt aggrrphaw aggrrpintr aggrrpoact aggrrpoaerr aggrrpoarq aggrrporeq aggrrpores aggrrporev aggrrporqe aggrrporqv aggrrpotst aggrrppfa aggrrppfb aggrrppfc aggrrppfd aggrrppfe aggrrppff aggrrppfg aggrrppfh aggrrppfi aggrrppfj aggrrppfk aggrrppfl aggrrppfm aggrrppfn aggrrppfo aggrrppfp aggrrppfq aggrrppfr aggrrppfs aggrrppft aggrrppfu aggrrppfv aggrrppfw aggrrppfx aggrrppfy aggrrppfz active time secs device retry short graceful long hard errdisabled down delay up delay aggregated transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receive rate transmit rate receiverate transmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransmitratereceiveratetransemiteatereceiveeatetraneteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteatereteateeataeteateseatae489999999999999999999999999999999999999999999999999999999999e48e48e48e48e48e48e48e48e48e48e48e48e48e48e48e48e4