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This is the support site for Andrews & Arnold Ltd, a UK Internet provider. Information on these pages is generally for our customers but may be useful to others, enjoy!

B10B Factory Reset: Difference between revisions

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"save_default clean" needs to be run from zycli
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The supervisor account uses a password which is automatically generated by the device, and unique to each device. Its format is 8 hexadecimal digits (each digit is 0-9 or a-f), and is believed to use the device's serial number as a starting point. AAISP do not know this password.
The usual way to obtain the supervisor password is to use software (e.g. hashcat) to crack the hashed version of the password which is held in the file /etc/passwd (before firmware version AAVF.10) or /etc/shadow (version AAVF.10 and later). The earlier firmware versions used an MD5 hash, and hashcat (on a fast machine) could crack the password in around 8 minutes. AAVF.10 switched to SHA-512 and hashcat takes ''much'' longer to crack the password (~9.5 hours).
 
Unfortunately as of firmware version AAVF.10 the admin user can't read the files /etc/passwd or /etc/shadow. This means you can't get the hashed version of the password to feed to cracking software.
==Reset to the ZyXEL Factory Settings==
 
To erase the default AAISP settings, the 'ROM-D' file needs to be cleared, this is done via the CLI (Telnet or SSH) using the supervisor user (see above) and then issuing the <syntaxhighlight inline enclose="none" lang="bash">zycli save_default clean</syntaxhighlight> command.
 
Here is an example:
VMG3925-B10B
Login: supervisor
Password: [your adminsupervisor password]
> zycli save_default clean
ROM-D cleaned.
</syntaxhighlight>
 
At this point you canshould reset the router for this to be applied - by holding in the reset button for 5 seconds. The router will then boot up in its original factory settings without any of the AAISP configuration settings. You can reset the router by holding in the reset button for 5 seconds.
 
In this state, the router has ZyXEL's default IP address, username and password.
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