I'm screwed - can't login

[Rick Stevens]

David G. Miller (aka DaveAtFraud) wrote:
> ndbecker2 at gmail.com wrote:
> 
>> My server has been running FC4 with all updates.  After my son just
>> accidentally unplugged it, it rebooted so that noone can login.  If 
>> booted
>> in text (mode 3), then after the login and password it just returns to
>> login prompt.
>>
>> It can't be booted in single user mode.  When this is tried, it says 
>> "going
>> into single user mode", but then starts all the same services as mode 3
>> (AFAICT) and acts just the same.
>>
>> I booted into rescue mode, did chroot /mnt/sysimage, and looked
>> at /var/log/messages and /var/log/secure.  Nothing intersting shown.
>>
>> I can't ssh in.  It just logs in and out immediately.
>>
>> Perhaps related, I had selected to disable selinux IIRC and it said it 
>> would
>> relabel on next boot.  Of course, it crashed before that happened.
>>
> First question is, have you tried any other accounts when attempting to 
> ssh in?  This could occur because your login shell has been set to 
> something like /bin/false or just something bogus.
> Try booting in rescue mode (again) and take a look at /etc/passwd and 
> see what it looks like.  It may have gotten zapped, /bin/bash may have 
> gotten zapped, etc.  If /etc/passwd looks good, try changing your login 
> shell to something like /bin/tcsh or /bin/ksh and then reboot and try 
> logging in again.
> Also, while in rescue mode, you might want to run fsck on which ever 
> partition holds /.  If the functionality isn't there in rescue mode, 
> download and burn a knoppix live cd, boot from it and see what needs to 
> be cleaned up.

Also check the root filesystem under rescue mode and make sure it's not
full.  The system will exhibit many of the same weirdnesses if / is
full.
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- Rick Stevens, Senior Systems Engineer     rstevens at vitalstream.com -
- VitalStream, Inc.                       http://www.vitalstream.com -
-                                                                    -
-    If Windows isn't a virus, then it sure as hell is a carrier!    -
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