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https://tools.ietf.org/rfc/rfc7239.txt 阅读全文
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https://ebtables.netfilter.org/documentation/docs.html https://ebtables.netfilter.org/misc/ebtables-man.html 阅读全文
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from：https://mirror.tuna.tsinghua.edu.cn/help/centos/ 清华CentOS 镜像使用帮助建议先备份 CentOS-Base.repo sudo cp /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d 阅读全文
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from：https://www.cnblogs.com/hellojesson/p/10037315.html 执行DROP DATABASE testdb;的时候提示： ERROR: database "testdb" is being accessed by other users DETAI 阅读全文
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1、ceontos bash: ip command not found yum install -y initscripts或者yum install -y iproute2 iproute2-doc bash: lsof: command not found yum install -y lso 阅读全文