Cause Analysis of Network Card and slow accident on Local area Network

Today found a fault: the company network on the external network card / slow and other phenomena. It is understood that no matter in the second or third layer under the ping Baidu is the phenomenon of packet loss. Tracert Baidu found that the interruption occurred after the Huaian external network, so it was judged as a telecom operator problem.

Call customer service call, door-to-door inspection, from the telecommunications equipment ping Baidu and Sina found that the phenomenon is normal, no packet loss phenomenon. Therefore, it is judged that there is a problem with the intranet, but the ping firewall found no problem.

Finally, after work, the problem of ping Baidu still exists, considering whether it is a network cable problem. Replaced the firewall to the third layer of the network cable, ping Sina normal Baidu is still switched.

After going home in the evening, I learned that there was a problem with the Baidu website, and the news reported that there was something wrong with Baidu's mobile terminal, so the second phase decided to use Sina and Weibo to do the PING package test, and found it was normal. I asked my colleagues that there was no slow access to the network card.

Summary: 1, can not trust Baidu and other well-known sites.

2. Pay attention to details. Sometimes the network cable can cause big problems.