一.启动redhat5.2,在3秒内按方向键(↓)
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二.进入下面页面后按"E"键
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三.在页面中选第二项(kernel 开头的),按"E"键
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四.在新页面中输入"空格+single"
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五.按回车,会回到第四步的页面,按"B"键系统会重启进入single模式,在"sh-3.2#"后面输入"passwd root",回车
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六.输入新密码,加车
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七.确认输入新密码,"回车"
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八.页面会输出"passwd:all authentication tokens updated successfully"
然后在"sh-3.2#"后输入"reboot"重启系统后,密码修改完成
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