網絡問題排查-整體思路

網絡問題排查思路

網絡模型

• 這是我們的網絡知識框架
  

數據傳輸路徑

• 這是知識框架中串聯的線
  

排查問題路徑-自下而上

鏈路層

1. 網線是否正常

]# ethtool ens33
Settings for ens33:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Full 
	Supported pause frame use: No
	Supports auto-negotiation: Yes
	Supported FEC modes: Not reported
	Advertised link modes:  10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Full 
	Advertised pause frame use: No
	Advertised auto-negotiation: Yes
	Advertised FEC modes: Not reported
	Speed: 1000Mb/s
	Duplex: Full
	Port: Twisted Pair
	PHYAD: 0
	Transceiver: internal
	Auto-negotiation: on
	MDI-X: off (auto)
	Supports Wake-on: d
	Wake-on: d
	Current message level: 0x00000007 (7)
			       drv probe link
	Link detected: yes

2. 網卡狀態

]# ip a s
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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:23:a7:0a brd ff:ff:ff:ff:ff:ff
    inet 192.168.74.130/24 brd 192.168.74.255 scope global secondary noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::ae29:4ab5:ecb8:118d/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

網絡層

1. IP|NETMASK|GATEWAY

]# vim /etc/sysconfig/network-scripts/ifcfg-ens33
TYPE=Ethernet
BOOTPROTO=static
NAME=ens33
UUID=bd385c8f-3c98-4afd-acc9-bc78f744bf16
DEVICE=ens33
ONBOOT=yes
IPADDR=192.168.74.130
NETMASK=255.255.255.0
GATEWAY=192.168.74.2

2. DNS
   1. /etc/resolve.conf
   2. nsloop
   3. dig
3. 路由
   1. ip route
   2. route

傳輸層

1. 服務端口
   1. ss
   2. netstat
   3. nmap
   4. telnet

應用層

1. 應用狀態
   1. ps
   2. systemctl
   3. log日志

防火牆

1. iptables
2. firewall

本文只是簡單介紹了下網絡的排查思路和涉及到的命令，命令詳細的解決請點擊各自鏈接查看
有些鏈接尚未可用，因為還沒整理處理....