LinuxQuestions.org - user groups and permissions questions

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user groups and permissions questions

hello

I have a mount point /data (/dev/sdc) I want all users in a certain group to be able to write to that folder. I created a group called data and added the users to that group.

I then:

Code:

chown -R root:data /data

user 'chris' wasn't able to write so I:

Code:

chmod -Rv 775 /data

Still nothing, tried:

Code:

chmod g+rwx /data

LS -la shows:

Code:

[root@fedora ~]# ls -la /data

total 32

drwxrwxr-x  4 root data  4096 Dec 22 10:17 .

drwxr-xr-x 24 root root  4096 Dec 22 07:32 ..

drwxrwxr-x  2 root data  4096 Dec 22 10:17 FC5Stuff

drwx------  2 root data 16384 Dec 21 12:08 lost+found

Also mtab

Code:

[root@fedora ~]# cat /etc/mtab

/dev/sda3 / ext3 rw 0 0

proc /proc proc rw 0 0

sysfs /sys sysfs rw 0 0

devpts /dev/pts devpts rw,gid=5,mode=620 0 0

/dev/sda1 /boot ext3 rw 0 0

/dev/sdc1 /data ext3 rw 0 0

tmpfs /dev/shm tmpfs rw 0 0

none /proc/sys/fs/binfmt_misc binfmt_misc rw 0 0

sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw 0 0

automount(pid1891) /net autofs rw,fd=4,pgrp=1891,minproto=2,maxproto=4 0 0

and fstab

Code:

[root@fedora ~]# cat /etc/fstab

LABEL=/                /                      ext3    defaults        1 1

LABEL=/boot1            /boot                  ext3    defaults        1 2

LABEL=/data1            /data                  ext3    defaults        1 2

devpts                  /dev/pts                devpts  gid=5,mode=620  0 0

tmpfs                  /dev/shm                tmpfs  defaults        0 0

proc                    /proc                  proc    defaults        0 0

sysfs                  /sys                    sysfs  defaults        0 0

LABEL=SWAP-sda2        swap                    swap    defaults        0 0

Am i missing something? Does it matter if the group i created is the users prinary group? I think that if I 777 the directory it would work but i don't want everyone to access it, just a few users.

I am running FC5 if it helps.

Thanks,

I don't see anything wrong. In particular, any member of group data should be able to write to /data/FC5stuff. Just to make sure nothing weird is going on (that I missed), I suggest you verify that root can write to this folder.

Beyond that, verify that chris is actually a member of group data by having that user type groups, which will list all groups that user is a member of. Or you can do this yourself by suing to that user.

Beyond that, be aware that groups are assigned at login. This means if a user is logged on when you change group assignments, that user will need to log out and log back in before the change takes effect.

Hey Chris,
Whats the permissions on /data itself? It too should be 755 but you might want to double check incase "chris" cant cd into /data.

Is Chris able to do other stuff? Can he go elsewhere or does "chris" have a problem everywhere?

Put in the output of:

Code:

ls -la / | grep data

cat /etc/groups | grep data

cat /etc/passwd | grep chris

Cheers
Arvind

Thanks blackhole54 for the help! Well since I am running linux and never have to reboot. I had never logged off user chris and once i did it all worked.

Thanks again gents and/or ladies!

Yes, I've been caught by that before. You can change the permissions and add a group to a user, but until they logout and login it does not take effect.

Bill