From Newsgroup: alt.os.linux
On Tue, 3/17/2026 7:36 AM, Jeff Gaines wrote:
I was having real problems seeing my HP Proliant Microserver on the network so I had a break from it and have put Linux Mint xfce on an Asus 170-P box.
Did all the same things and lo and behold I can see it on the network, I have clearly done something wrong on the HP.
I have a 4 TB Iron wolf drive (ext4) in the HP box with my multimedia on it, presumably all "owned" by "jeff".
If I move the drive to the Asus box do I need to chown all the data. I know in Windows it might tell you "jeff" is the owner but actually it's user 123456 who is actually the owner and you have to "take ownership" to access the drive if you move it between machines.
Many thanks.
The two situations have some similarities.
Windows uses numbers. The names are secondary and
form a convenient reference for the user. Notice how
my "Mere User" is account 1000! What a coincidence.
wmic useraccount get name,sid
Name SID
Administrator S-1-5-21-3769549767-1934783099-1503750287-500
Mere User S-1-5-21-3769549767-1934783099-1503750287-1000
Guest S-1-5-21-3769549767-1934783099-1503750287-501
When a Domain Server is present in the room, all accounts
can be consistent from machine to machine. Authentication then,
is against the Domain Server.
When no Domain Server is present (a home computer room), then
each machine can be different. Notice how the number on the end
can be different "due to some assignment sequence difference".
The machine across from me has three accounts, so they can't
all be 1000. They could be 1000, 1001, 1009
Machine #1
Jeff S-1-5-21-3769549767-1934783099-1503750287-1000
Machine #2
Jeff S-1-5-21-1111111111-2222222222-222222222-1001
*******
Linux has at least some similarities to Windows. Unix has some
global resources, that I expect Linux would have an equivalent.
But at least as home users, we are familiar with "number as king".
If we plug in a foreign disk, and the owner is 9999:9999 on the file user:group, and further, the password or shadow has no entry for 9999,
then... just the number is printed as the owner. Windows does
similar. For weird foreign offerings, the SID is a number and
we can see a number or a measure of weirdness for a short time.
Windows allows adding multiple users as file ownership. This means
these two can "own" the file on my S: drive. The second one
may have been assigned automatically by the system. Or, we can
"force it" of course. The green bar in File Explorer may be present
while a person belonging to the Administrator Group, receives
an Implicit Takeown by the OS, due to the level of elevation
that user possesses. A Limited User could not coerce the situation.
S-1-5-21-3769549767-1934783099-1503750287-1000
S-1-5-21-1111111111-2222222222-222222222-1001
Linux has chown and chmod for forcing things. If you're
not the owner of a file, running elevated as the root user
by using sudo, allows twisting things as you desire.
If we saw
9999 9999 MerryChristmas.txt
we could do
sudo chown jeff:jeff MerryChristmas.txt # change 9999:9999 to 1000:1000
chmod 644 MerryChristmas.txt # Now that we own the file, sudo is not required.
# At the very least, I want a read-bit at some level.
vi MerryChristmas.txt # Usually the machines have a "vi" editor for old time sake. :q! to exit :-)
If Jeff happens to be 1000:1000 after one machine install
and 1001:1001 on another machine install, that is "foreign enough"
to be just as broken as a 9999:9999 strawman.
I'm not aware of Linux having "implicit takeown", so
you're more likely to have to intervene. The form of
the command can sometimes require a bit more cleverness,
as "whacking everything with a sledge" just is not subtle enough.
Windows has rules just like Linux, and you have to be very careful
to not be waving Takeown around from the top of C: . In a similar
fashion, "doing a Windows 98" onto your slash / tree, would be
a disaster. The /etc is supposed to be owned by root but
readable by Jeff, and we do not want to leave the permissions
too open after messing in there. Windows would not like it
either, "if the kernel was 777" for example. Windows has more than
one protection mechanism, as security overlays, to help "curve
the properties in the right direction". Linux expects
there are adults in the room, and when you make the kernel
777, "you must have done that for a reason" :-) Maybe you
learned that in your IT administrator course.
I don't pretend to know all the rules for either system.
Which is why I cannot provide a much more meaty answer
than this. Suffice to say, you may encounter situations
where a number shows up. There is an option in the
mount command, related to an account number, but this
can be part of causing a foreign file system to
"fit into the stat() scheme and have a sensible value
for a property the file system does not have (FAT32 owner)".
https://linux.die.net/man/8/mount
uid= gid=
Paul
--- Synchronet 3.21e-Linux NewsLink 1.2