Accidental deletion iptables cause a system crash

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This link: https://blog.csdn.net/milugloomy/article/details/83745140

background

Test Server version centos7.2 Ali cloud, built-in firewall to firewall. Unfamiliar because of the firewall, the installation of iptables, the command is:

yum install iptables

After configuring iptables, we found particularly slow application access, and some also need to request a minute or so, view the application log, no problem. So turn off iptables, but access is still slow, normal to think of before, after the installation of iptables so slow, he unloaded try again. Uninstall command as follows:

yum remove iptables

This delete, print out a lot of the console log, log loading the application did not so much, why would so many deleted. Heart of a bear, and then found that services are not accessible, the remote connection is also not on the connection. Rom tried for a long time, so log on Ali cloud console, find this service networking are gone, that network service has been deleted! ! !

rescue

Online search has learned a lot, this command will cause the system to rely on many of the necessary components are deleted together, because there is no network card configuration information can not be networked. At this point the server as a minimal install of centos, only manually configure the network card a static IP. But it seems that Ali cloud because of security policies, that he could not obtain IP Gateway really need.

Ali goes only one way to start the engineer to explain the situation, Sipilailian let them help.

Fortunately, Ali cloud operation and maintenance engineers to the force, a night time, the network system restored, but also remotely connected.

in conclusion

After you have to be careful, especially when encountered delete! (Do not accidentally delete library really become Paolu (T ▽ T))