Lost Linux root password recovery - multiple ways to reset or recover forgotten root password
Have you ever forgotten your root password and needed to reset it? I have a very good memory. I remember most of my client's
passwords (there are a few I forget regularly for no reason that I
can understand, but I really do know most), I remember telephone
numbers, and of course I know my own passwords. That last isn't as
easy as it might sound, because I have quite a few different
systems and each has its own password, but though I might use the
wrong one now and then, I'll get it on the second or third try.
If you just need to CHANGE root's password, and you are already logged in as root, just type "passwd" at a shell prompt to reset it.Well, not this time. A while back I installed
system here, and today I wanted to look at something and .. what
was the root password? Hmm, not that.. how about? .. nope, well it
must be.. darn! This is worth checking Twice I have been at customer sites with a lost root pasword
and found that root was already logged in on one of the Alt screens. It is worth checking.. check "w" too. It's a long shot,
but somebody might be in a long forgotten window. Let's try the easy way first
Before we go to far with this, some systems use "sudo" and
may have configured your ordinary user account to use it with your
own password. Just on that chance, try typing:sudo su -
at a shell prompt. If it asks for a password, just type in your
usual password. If you get a "#" prompt, you are now logged in as root and
can reset or change your password however you like.You could now even use a program like Jack the Ripper if you
would rather not change the password or are curious as to
what it was.If you can't do sudo, it might be harder to recover a
forgotten password.. Try single user mode But let's try it the easy way first. The next thing to try is to boot to single user mode. This MIGHT not work for you, because your system might be configured to still ask for a root password to get to single user mode. If that's the case, we'll use another trick that replaces init with /bin/bash.Reboot (ctrl-alt-delete or the reset button or pull the plug if that's what it takes)to get access to your boot loader - LILO or Grub.Note: getting access to the Grub command line can be annoying. Older
versions told you what to do.
doesn't: Hold down SHIFT to display the menu during boot (formerly ESC in GRUB legacy). If you don't see either a LILO or GRUB boot screen, try hitting CTRL-X to get one. Once you have that, if it's LILO, just type "linux single" and that should do it (assuming that "linux" is the lilo label, which it probably is). If GRUB, hit 'e", then select the "kernel" line, hit "e" again, and add " single" (or just " 1") to the end of the line. Press ENTER, and then "b" to boot. (More modern grub uses "a" to append to the boot line)You should get a fairly normal looking boot sequence except that it terminates a little early at a bash prompt. If you get a "Give root password for system maintenance", this isn't going to work, so try the "init" version below.If you do get the prompt, try typing "passwd" now. If that works, you are good to go. Reboot and consider .If not, the / filesystem may not be mounted rw (although "mount" may say it is). Domount -o remount,rw /
and try "passwd" again.
If that doesn't work (it might not), just type "mount" to find
out where "/" is mounted. Let's say it is on /dev/sda2. You'd then
type:mount -o remount,rw /dev/sda2
If you don't know what filesystems are there, 'fdisk -l'
will tell you.Note that you might have to specify a filesystem type: "mount -o remount,rw -t ext3 /dev/sda2", for example.If you can do this, just type "passwd" once you are in and
reset it to whatever you like.
One more try before boot media Another trick is to add "init=/bin/bash" (LILO "linux init=/bin/bash" or add it to the Grub "kernel" line). This will dump you to a bash prompt much earlier than single user mode, and a lot less has been initialized, mounted, etc. Note that other filesystems aren't mounted at all, so you may need to mount them manually if you need them. Look in /etc/fstab for the device names or use "fdisk -l" to list available partitions.You almost certainly need to remount root with this trick. Then try "passwd". If you have to use boot media However, some systems are protected with boot loader passwords that won't let you do that without THAT password. If the boot loader is password protected, you need to boot from other media - for newer systems, the install CD probably has the recovery tools for that ("linux rescue" for example). You could use your install disks or download something like . If using something like "linux rescue" or other boot media, if the recovery disk doesn't automatically mount your disk, you need to do it manually. This shouldn't be difficult unless you have an unusual disk controller. For example, a Compaq raid controller will probably be /dev/ida/c0d0. Find the partitions by using fdisk /dev/ida/c0d0 (just "p" and quit) and then mount what you need.You might "mount /dev/hda2 /mnt". Once you have your
filesystem mounted, you might try "chroot" and then use "passwd" to fix things up. Say you have the old drive at "/mnt" - type "chroot /mnt" and then use "passwd".Or just edit /mnt/etc/shadow to remove the password field: move to just beyond the first ":" and remove everything up to the next ":". With vi, that would be "/:" to move to the first ":", space bar once, then "d/:" and ENTER. You'll get a warning about changing a read- that's normal. Before you do this, /mnt/etc/shadow might look like:root:NFmV6tr$rT.INHxDBWn1VvU5gjGzi/:99:7:-1:-1:
bin:*:99:7:::
daemon:*:99:7:::
adm:*:99:7:::
and after, the first few lines should be:root::99:7:-1:-1:
bin:*:99:7:::
daemon:*:99:7:::
adm:*:99:7:::
You'll need to force the write: with vi, ":wq!". (If that still
doesn't work, you needed to do the -o remount,rw, see above). If it does work, you have reset root to not have a password. You'll want
to change that soon, of course.If you are having trouble with editing (you really do have to learn vi one of these days), you could just (after making a copy, of course) just
"root::12832:0:::::" & /mnt/etc/shadow
or, if you were in single user mode
"root::12832:0:::::" & /etc//shadow
and then fix things up when rebooted.Don't forget to cd back to your boot media and umount before typing "reboot". Final resort If all else fails, you can pull this drive (or install another drive in this machine) and mount it from another running Linux. Then recover/reset the root password as explained above.
All set? Keep this in mind if you have a Linux machine in a publically accessible place : without more protection, it's not usually hard to recover a lost root password, which means it's just as easy for someone to CHANGE it, or access root without your knowlege. The only difference between "break root" and this is intent. Hacking root's password can be accomplished with these same methods, so if
you want to protect your machine, you may want to close these off.Consider that nowadays a USB stick can be boot media.
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Buy Kerio from a dealer who knows tech:
I sell and support孕7、8周，经腹B超还是看不清，肿么办？_我末次月经是8.1_宝宝树
孕7、8周，经腹B超还是看不清，肿么办？
我末次月经是8.15号，所以按这个推算，我应该是56天了，但是我月经周期长，不知道准不准，上次去检查的时候，45天，做的经阴部B超，只发现胎囊，孕黄囊，胎芽胎心不清，验血结果是，孕酮有点低，16.2，医生让吃黄体酮，和保胎药，今天去拿叶酸的结果，叶酸代谢能力弱，有中度风险，本来医生要给开药的，后来说先做B超看看有没有胎心胎芽了，强烈要求做的，经腹部的，因为之前有听说经阴部的不太好，然后就中午回家使劲憋尿，下午去检查，医生说还是看不清，建议改成经阴部的，然后跟家人商量了一下，先不做，现在好害怕没有怎么办，也不知道怎么办了，是过几天再看看，还是换家医院呢，有没有跟我差不多情况的，我也怀疑我的天数没那么多，因为宝宝树上消失是50天，医院算的比这个多一周，哎怎么办啊，大家出出主意
孕囊大小长得怎么样?你直接做阴超，早孕阶段做阴超看得准确!我去年情况和你差不多，8.29末次，十一开始抽血+B超，一直到10.20抽血hcg才看出来，11.1B超才看到囊，整个十月和十一月一周一个B超，我闺女现在好好的!
孕酮不算太低，我查出来怀孕的时候才5.6
胎囊是1.9 1.7 1.0
胎囊是1.9 1.7 1.0
回复 &高高木秀于林&
16:32:10发表的
孕囊大小长得怎么样?你直接做阴超，早孕阶段做阴超看得准确!我去年情况和你差不多，8.29末次，十一开始抽血+B超，一直到10.20抽血hcg才看出来，11.1B超才看到囊，整个十月和十一月一周一个B超，我闺女现在好好的!
孕酮不算太低，我查出来怀孕的时候才5.6
孕7、8周，经腹B超还是看不清，肿么办？相关的更多内容:
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需要账号和密码的外链可能是钓鱼网站，为了您的账号和财产安全，请勿提供任何有效信息！EasyBCD 2.1 使用方法我c盘xp。G盘win7。现在我想用EasyBCD 来添加启动菜单，不知道怎么用。_百度知道
EasyBCD 2.1 使用方法我c盘xp。G盘win7。现在我想用EasyBCD 来添加启动菜单，不知道怎么用。
是在xp中运行EasyBCD 还是在win中运行EasyBCD 。
该怎么设置，我用EasyBCD 添加过，但在启动是不能引导。求解。
提问者采纳
我今天刚装了一下WIN7系统，装在C盘；原来的系统XP，装在G盘。装完之后，二、EasyBCD v2.0使用教程及注意事项 1、EasyBCD的安装说明 该软件可以在
我在xp中运行时，EasyBCD 需要我打开一个*.bcd文件。
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其他2条回答
那就要看你那个盘是活动的了！你c盘是xp应该c盘是活动的 那就在c盘解压
easybcd的相关知识
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出门在外也不愁1.下载需要的工具
CDlinux&&下载地址 &&/s/1sj7FEJb & 为CDlinux 集成wifi破解工具的 0.9.7.1版本
EasyBCD 2.2 下载地址网上自行搜索
2.配置引导
2.1 将CDlinux-0.9.7.1.iso 更名为&CDlinux-0.9.7.1.iso,放在任意硬盘根目录下（推荐C盘）
2.2 进入EasyBCD &添加新条目-&NeoGrub-&安装
2.3 打开C盘下C:/NST/menu.lst &或者 点击配置
添加以下内容（不包括前面序号）
1 title CDlinux
2 find --set-root /CDlinux.iso
3 map --mem /CDlinux.iso (hd32)
4 map --hook
5 kernel (hd32)/CDlinux/bzImage quiet
CDL_DIR=/ CDL_IMG=CDlinux.iso
6 initrd (hd32)/CDlinux/initrd
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