本博文来自老男孩Linux运维博客。有问题欢迎进入博主专页进行互动讨论！博文地址：http://oldboy.blog.51cto.com/2561410/1610998老男孩老师从课堂上分享sed实用技巧实际教学内容1.在指定行前插入两行内容，分别是oldboy和oldgirl.提示：要修改的文件内容必须大于等于2行sed-i'2ioldboy\noldgirl'sshd_config2，企业实战示例：快速更改SSH配置（一键完成添加多个参数）添加：[root@oldboyssh]#sed-i'13iPort52113\nPermitRootLoginno\nPermitEmptyPasswordsno\nUseDNSno\nGSSAPIAuthenticationno'sshd_configView:[root@oldboyssh]#sed-n'13,17p'sshd_configPort52113PermitRootLoginnoPermitEmptyPasswordsno\nUseDNSno\nGSSAPIAuthenticationno'sshd_configView:[root@oldboyssh]#sed-n'13,17p'sshd_configPort52113PermitRootLoginnoPermitEmptyPasswordsno\nGSSAPIAuthenticationno'sshd_configView:[root@oldboyssh]#sed-n'13,17p'sshd_configPort52113PermitRootLoginnoPermitEmptyPasswordsnoAPI修改为UseDNSnoication的参数可以快速修改使用方法如下《-----sshConfig修改ssh默认登录端口，禁止root登录------------------------#》\cp/etc/ssh/sshd_config/etc/ssh/sshd_config.$(date+"%F"-$RANDOM)sed-i's%#Port22%Port52113%'/etc/ssh/sshd_configsed-i's%#PermitRootLoginyes%PermitRootLoginno%'/etc/ssh/sshd_configsed-i's%#PermitEmptyPasswordsno%PermitEmptyPasswordsno%'/etc/ssh/sshd_configsed-i's%#UseDNSyes%UseDNSno%'/etc/ssh/sshd_configsed-i's%GSSAPIAuthenticationyes%GSSAAPIAuthenticationno%'/etc/ssh/sshd_configegrep"UseDNS|52113|RootLogin|EmptyPass|GSSAAPIAuthentication"/etc/ssh/sshd_config提示：如果是指定行修改，也可以是：sed-i'2735s/admin_tenant_name=service/adminadmin_tenant_name=admin/'nova配置文件
