local device (USB-stick) and users groups problem

[Ismail ISLEYEN]

Hi,

I have installed Edubuntu 7.10 on Dell Poweredge 2800 server (Xeon 3.6
Ghz x 2, 12 GB Ram, 146 x 4 Hdd) in computer room. There are 40 HP T5000
(T5525) clients to connect to the server. I have an urgent problem to be
solved as soon as possible. I would appreciate any help.

The problem is as follows:

1. Installation and updates are OK.

2. 12 RAM is provided with "linux-image-server".

3. etc/ltsp/dhcpd.conf a client mac addresses are added and 192.168
addressess are changed as 10.0.

4. Details for     etc/network/interfaces  ---> eth1  are changed as
follows:
    address 10.0.0.254
    netmask 255.255.255.0
    network 10.0.0.0
    broadcast 10.0.0.255

5. Users are added to the system through graphic interface

6. Users are arranged as follows:
        /etc/hosts a
        10.0.0.101   thin1
        10.0.0.102   thin2
        .........

7. etc/default/dhcp3-server   ----> is changed as "eth1"

8. I have configured lts.conf file as explained in Asmo Koskinen's
e-mail
(https://lists.ubuntu.com/archives/edubuntu-users/2008-March/003805.html)
        [default]
        SOUND=True
        LOCALDEV=True
        LDM_SERVER="10.0.0.254"
        LDM_DIRECTX=True
        X_RAMPERC=80
        X_COLOR_DEPTH=16

To sum

1. USB flash drive or "local device" is active only in the first user,
others cannot use USB flash drives. For example while one who logs in
with thin1 can use USB flash drive, other users  who loged in later
cannot use USB flash drive. I tried this in different accounts and
clients but no way.

2. The group of users which I configure through graphic interface
apeears as thin2 after the second user. Is it normal?
        user       group
        thin1      thin1
        thin2      thin2
        thin3      thin2
        thin4      thin2
        .....       thin2

3. When 25 users are logged in, the usage of RAM is 30%, and of
processor is 45% but I cannot use student control panel. What is the
possible reason for this?

4. With 25 users logged in some users have "gnome-desktop-manager" error
and cannot open desktop. Although I deleted all files in user folder and
removed them from tmp folder, the system gives the same error. What can
you suggest as solution?

I need to solve the above mentioned problems before open the system to
users.

I sincerely thank everybody in advance for their time and help.