How to use the ping command to detect network problems?

Ping command can be said to be one of the most commonly used command line tools in network management. Ping can be used to diagnose network problems very quickly. Today, I'm going to teach you how to use ping to detect network problems.

When the network is too slow to connect to the network, follow these steps to execute the ping command:

1. Ping private network gateway

First of all, ping the gateway address of the private network to ensure that the private network is unblocked. As shown below:

The packet loss rate of the private network should be 0, the wired ping value is generally within 1ms, and the wireless ping value is between 1ms-20ms. If there is packet loss or the ping value is high, then the problem lies in the intranet. Need to troubleshoot internal network cables, loops, switches and other equipment problems.

2. Ping public network IP

When there is no problem with the private network, we need to ping the IP address of the public network to check whether the public network is smooth. As shown in the figure below, 114.114.114.114 is a commonly used DNS server. Because 114on the public network, the ping value is higher than that of the private network, generally between 1ms-50ms.

The ping can be connected and the ping value is normal without packet loss, which means that the external network is normal, otherwise the external network is abnormal, it is necessary to troubleshoot the router and wan port line problems.

3. Ping public network domain name

If the external network can be connected to ping, but still can not be connected to the network, that is generally the problem of dns. It can be judged by the ping domain name. As shown in the figure:

Normally, the IP address can be resolved through the domain name. If the IP cannot be parsed, there is a problem with the DNS. If the resolution is correct, but still can't open the site, that's the reason for the browser.

4. WFilter's network health detection plug-in

In WFilter's "plug-in management", there is a network health detection plug-in, which can automatically detect ping, arp, tracert and so on, thus detecting most of the network problems with one click.

The diagnosis of network problems requires rich experience and clear logical judgment, and good tools need to be able to use.