Networking and Passwords - What is and isn't possible?

From: Mike (mikesjunkcatcher@earthlink.net)
Date: 04/11/03 

From: Mike <mikesjunkcatcher@earthlink.net>
Date: Fri, 11 Apr 2003 05:34:57 GMT

My cousin works for Sun and had an Sparc Ultra 1 with Solaris 8 he gave me
today. We have some disagreement about what is possible.

I have two questions.

[[QUESTION 1]]
Is it possible to have three computers and a DSL modem plugged into a hub
where one computer accepts DHCP assignment from the DSL modem, does NAT and
provides DHCP for the other computers but the DSL modem does not receive
DHCP assignment?

I have three computers I want to have Internet access through one DSL modem.
This is not a normal DSL modem. My ISP uses PPPoE which is handled onboard
by the DSL modem. The DSL modem does DHCP assignment for up to 10 devices
but only does NAT for one IP address. If the DSL modem receives a DHCP
assignment it stops doing PPPoE (and I do want it to do PPPoE.)

Currently I have only two computers on the network. The one that is
connected to the DSL modem has two ethernet cards and accepts DHCP on the
one connected to the DSL modem and provides DHCP on the other. The second
computer connects to the first and receives that DHCP assignment. The
computer connected to the DSL modem then does NAT for the second computer.

It may be better to see it like this:

CURRENT:
[DSL] provides DHCP (172.16.1.10) and NAT -to--> Eth-1st on Computer-1st
        Computer-1st provides DHCP (192.168.0.254) and NAT on Eth-2nd

Computer-2nd accepts DHCP (192.168.0.254) from Computer-1st
        and uses Computer-1st as an Internet gateway.

FUTURE (Hopefully)
[DSL] provides DHCP (172.16.1.10) and NAT -to--> HUB
        BUT [DSL] must NOT receive DHCP assignment

Computer-NEW accepts DHCP (172.16.1.10) from HUB [DSL]
        and provides DHCP (192.168.0.254/253) and NAT to HUB
Computer-1st and Computer-2nd accept DHCP (192.168.0.254/253) from HUB
        and use Computer-New as an Internet gateway

Frankly I'm not sure this is possible but he thinks it is so I'm asking the
experts here.

[[QUESTION 2]]
How do I remove the root password, provided there is no bios password and I
have physical access?

He also gave me the root password BUT I believe it is possible (he doesn't)
to remove the passwords by booting from floppy or bootable CD, mounting the
drive and editing the password files. I would like to return the sealed
envelope containing the password he gave me without needing to open it to
show it is possible.

I think I can boot from diskette and take the following steps:
mount /dev/some-hard-disk /mnt
cp /mnt/etc/shadow /mnt/etc/shadow.original
vi /mnt/etc/shadow
        (remove the second field for root which should be the encrypted password)
:wq!
shutdown -r now

And not need a password to log in as root after rebooting.

I don't know what the hard disk name will be and I would like to get
confirmation that this will probably work without doing any damage.

Any and all help or suggestions are welcome.

Thanks,
~Mike

Relevant Pages

  • Re: Networking and Passwords - What is and isnt possible?
    ... If on a hub then each computer ... the onboard firewall included with the DSL modem firmware. ... computers from receiving DHCP by adding a second DHCP server to the mix. ...
    (comp.unix.solaris)
  • Re: Workgroup Network Problems
    ... which was the DHCP. ... Last week I changed to a DSL modem and a new switch. ... now the XP machine can't see the other computers in the ... If you have Windows 98 and Windows XP on the LAN together, ...
    (microsoft.public.windowsxp.network_web)
  • Re: Networking and Passwords - What is and isnt possible?
    ... how do I keep the DSL modem from receiving DHCP ... I thought if it was connected to the hub then it would receive ... >> hub where one computer accepts DHCP assignment from the DSL modem, ... >> does NAT and provides DHCP for the other computers but the DSL modem ...
    (comp.unix.solaris)
  • Re: Networking and Passwords - What is and isnt possible?
    ... > hub where one computer accepts DHCP assignment from the DSL modem, ... > does NAT and provides DHCP for the other computers but the DSL modem ...
    (comp.unix.solaris)
  • Re: Networking and Passwords - What is and isnt possible?
    ... > Is it possible to have three computers and a DSL modem plugged into a hub ... > provides DHCP for the other computers but the DSL modem does not receive ... > DHCP assignment? ...
    (comp.unix.solaris)