一、網絡狀態查看：

ss

netstat

iftop

iptraf

ethtool

ss代替netstat

ss -t -a

Display all TCP sockets.

ss -t -n--查看所已經連接上的TCP

ss -t -l -n--查看所有正在監聽的TCP

ss -u -a

Display all UDP sockets.

ss -o state established ’( dport = :ssh or sport = :ssh )’

Display all established ssh connections.

ss -x src /tmp/.X11-unix/*

Find all local processes connected to X server.

ip代替ifconfig/route

ip link set DEVICE { up | down }--開啟或者關閉網卡

ip link show [ DEVICE ]--查看網卡連接狀態

ip addr { add | del } IFADDR dev STRING--添加IP地址

ip addr show {eth0 | eth1}--查看某個網卡的IP地址

ip route list--查看路由表

ip route add to 192.168.10.0/24 via 192.168.100.1

ip route add to 192.168.20.0/24 dev eth0--添加一條默認路由

ip route add to 0/0 via 192.168.100.1--添加默認路由

ip route del to 0/0 dev eth0--刪除默認路由

# ethtool eth0－－查看當前網卡的硬件信息

Settings for eth0:

Supported ports: [ TP ]

Supported link modes: 10baseT/Half 10baseT/Full

100baseT/Half 100baseT/Full

1000baseT/Full

Supports auto-negotiation: Yes

Advertised link modes: 10baseT/Half 10baseT/Full

100baseT/Half 100baseT/Full

1000baseT/Full

Advertised auto-negotiation: Yes

Speed: 1000Mb/s

Duplex: Full

Port: Twisted Pair

PHYAD: 1

Transceiver: internal

Auto-negotiation: on

Supports Wake-on: g

Wake-on: d

Link detected: yes

二、更改速率及網卡的協商模式：

# ethtool -s eth0 speed 100 duplex full autoneg off

bond多網卡

網卡綁定技術有助于保證高可用性特性并提供其它優勢以提高網絡性能,在這介紹的Linux雙網卡綁定實現就是使用兩塊網卡虛擬成為一塊網卡,這個聚合起來的設備看起來是一個單獨的以太網接口設備,通俗點講就是兩塊網卡具有相同的IP地址而并行鏈接聚合成一個邏輯鏈路工作,這樣即使其中的一塊物理網卡出現故障,也不會導致連接中斷.

網卡綁定就是多張網卡邏輯上作為一張網卡用.可分為,負載均衡綁定和冗余綁定兩種.

1、負載均衡：

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

DEVICE=bond0

IPADDR=192.168.0.100

NETMASK=255.255.255.0

BROADCAST=192.168.0.255

NETWORK=192.168.0.0

GATEWAY=192.168.0.254

ONBOOT=yes

BOOTPROTO=static

TYPE=BOND

BONDING_OPTS="mode=0 miimon=50"

2.編輯各網卡的配置文件

# vim /etc/sysconfig/network-scripts/ifcfg-eth0

BOOTPROTO=none

TYPE=Ethernet

DEVICE=eth0

ONBOOT=yes

MASTER=bond0

SLAVE=yes

USERCTL=no

# vim /etc/sysconfig/network-scripts/ifcfg-eth1

BOOTPROTO=none

TYPE=Ethernet

DEVICE=eth1

ONBOOT=yes

MASTER=bond0

SLAVE=yes

USERCTL=no

3、加載內核模塊

# vim /etc/modprobe.conf

alias bond0 bonding

options bond0 miimon=50 mode=0--mode=[0(banance-rr) | 1(active-backup)]

# modprobe bonding

4、重啟服務：

# /etc/init.d/network restart

5、查看

# cat /proc/net/bonding/bond0

Ethernet Channel Bonding Driver: v2.6.1 (October 29, 2006)

Bonding Mode: load balancing (round-robin)

MII Status: up

MII Polling Interval (ms): 100

Up Delay (ms): 0

Down Delay (ms): 0

Slave Interface: eth0

MII Status: up

Link Failure Count: 1

Permanent HW addr: 00:1b:b9:58:8b:b2

Slave Interface: eth1

MII Status: down

Link Failure Count: 0

Permanent HW addr: 00:07:40:6c:ac:c8