Ubuntu Howto - What is the "/etc/shadow" file - the file stores the actual password in encrypted format for user's account with additional properties related to user password, fields colon as a delimter.
Not all Unix systems uses the shdaow file, as some traditional Unix systems still uses the /etc/passwd to store one way encrypted password, one way of finding out if your system uses a shadow file is to check the passwd file if the foremat of it is something like the one below the chances are your using a shadow file, or just use the command "ls -la /etc/ | grep -i shadow" to see if shadow file exist, since this is an Ubuntu howto and I pressume you using an Ubuntu distribution then you are definitely using a shadow file :)
mileyugly:x:2006:10000:Miley:/home/mileyugly:/bin/bash
The "/etc/shadow'' file not only contains the password but also contains account expiration information, its look like the sample below
mileyugly:Od9mbkrTLchV.:11763:0:99999:7:::
The field are seperated by colon
First feld - Username field 8 characters, its a match with the entry on passwd
Second field - Password Field 13 characters, most of the time encrypted, no entry means no password is needed to login
Third field - Number of days since password has been changed, since Jan 1, 1970.
Fourth field - Number of days before password may be change 0 indicates password can b changed anytime
Fifth field - The maximum number of days the password is valid
Sixth field - The number of days before password is to expire that user is warned that password must be changed
Seventh field - The number of days after password expires that account is disabled
Eigth field -days since Jan 1, 1970 that account is disabled i.e. an absolute date specifying when the login may no longer be used
To change your password, use the passwd command.
I hope this Ubuntu howto help you, enjoy!
More Ubuntu Howto Links below
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Ubuntu Howto | Multiple IP | IP Aliasing | Howto
Ubuntu Howto - Sharing folder with Windows on Ubuntu using Samba
Not all Unix systems uses the shdaow file, as some traditional Unix systems still uses the /etc/passwd to store one way encrypted password, one way of finding out if your system uses a shadow file is to check the passwd file if the foremat of it is something like the one below the chances are your using a shadow file, or just use the command "ls -la /etc/ | grep -i shadow" to see if shadow file exist, since this is an Ubuntu howto and I pressume you using an Ubuntu distribution then you are definitely using a shadow file :)
mileyugly:x:2006:10000:Miley:/home/mileyugly:/bin/bash
The "/etc/shadow'' file not only contains the password but also contains account expiration information, its look like the sample below
mileyugly:Od9mbkrTLchV.:11763:0:99999:7:::
The field are seperated by colon
First feld - Username field 8 characters, its a match with the entry on passwd
Second field - Password Field 13 characters, most of the time encrypted, no entry means no password is needed to login
Third field - Number of days since password has been changed, since Jan 1, 1970.
Fourth field - Number of days before password may be change 0 indicates password can b changed anytime
Fifth field - The maximum number of days the password is valid
Sixth field - The number of days before password is to expire that user is warned that password must be changed
Seventh field - The number of days after password expires that account is disabled
Eigth field -days since Jan 1, 1970 that account is disabled i.e. an absolute date specifying when the login may no longer be used
To change your password, use the passwd command.
I hope this Ubuntu howto help you, enjoy!
More Ubuntu Howto Links below
Tech Blog Special Build your own IDS or IPS
Ubuntu Howto | Multiple IP | IP Aliasing | Howto
Ubuntu Howto - Sharing folder with Windows on Ubuntu using Samba
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