Linux Terminal Server Project (LTSP) is a free open source Linux add-on package that allows several people with low-power computers (terminals) to use the computing power of one more powerful computer (server). At the same time, all applications run on the server, and the terminals, also called thin clients (or X-terminals), simply accept the video sequence sent by the server, and do not process anything except it. Typically, the terminal is a low-power computer, it may even not have a hard disk, as a result of which it can work quieter than a regular desktop computer.
Thin client technology is widely used in institutions such as schools, as it allows students to access computers without buying or upgrading existing desktop computers. With a shortage of computers at school, organizing new thin client machines is less expensive than buying full-fledged computers. And if the school is faced with the issue of updating computer technology, then this issue can be postponed by reconfiguring computers to thin clients, since even a relatively slow processor has sufficient performance for the thin client role. And then it is enough to purchase one powerful computer that will act as a server for the rest.
In addition to cost savings, the educational institution also gains more control over the use of computing resources by students. Examples of using LTSP are AbulÉdu, Edubuntu , K12LTSP, and Skolelinux . LTSP is supported by Cutter project and Deworks.
The founder and leader of the LTSP project is Jim McKillan, LTSP is licensed under the GNU General Public License .
Content
Download Process
- On the LTSP server in the chroot environment, a minimal Linux-based operating system and X Window System are prepared;
- Loading minimal environment:
- either from the hard drive / USB drive or CD-ROM, the computer boots the Linux kernel, which initializes the hardware;
- or, in the case of a thin client, network boot is used with PXE - part of the firmware of the network card, which receives its IP address and the address of the boot server (LTSP server) via DHCP . The bootloader receives the kernel and initrd via TFTP from the LTSP server. The kernel again receives its ip-address and the server address from which you can connect the root file system (prepared in advance in chroot), and then mounts it using the Network File System (NFS) or Network Block Device (NBD) protocol.
- A loaded system starts the X Window System and XDMCP graphics system. Starting with the 5th version of LTSP, the client first establishes an SSH tunnel to the graphical environment of the LTSP server, through which it locally launches LDM (LTSP Display Manager). From this moment, the programs are launched on the LTSP server, and are displayed and managed on the client.
History
| Purpose | LTSP 4 | LTSP 5 (MueKow) |
|---|---|---|
| GUI Export | XDMCP | ssh -X |
| Remote login ( X display manager ) | KDM / GDM | LTSP Display Manager (LDM) |
| Distribution method | LTSP tarball | Native distribution |
| Root filesystem | Nfs | NBD |
| Authenticating server | XDMCP server | Ssh server |
Fat Customers
LTSP v5.x adds support for a special type of thin client known as fat clients. With the advent of inexpensive and at the same time quite powerful computers, it became possible to run applications locally on a thin client, while maintaining the manageability of such a solution. In the case of the thick LTSP client, the root file system is not a truncated chroot, but a full Linux installation like chroot. The thick client uses LDM for authentication on the LTSP server and mounts user home directories using SSH and FUSE . Thick clients use their own processor and RAM, which gives some advantages:
- the LTSP server does not suffer from users abusing resources and affecting the performance and availability of the LTSP server to other users;
- multimedia and 3D applications work better and less strain on the network.
LTSP is notable for offering computers the ability to mount the root file system over the network, but run applications locally. On the Windows platform, the closest equivalent is the use of technologies such as Intel vPro to launch the client-side hypervisor and mount the root file system image using iSCSI .
See also
- Edbuntu
- Vnc
- freenx
- Thinstation
- Ndiyo
- rdesktop
- Multi terminal system
Notes
- ↑ Jonathan Carter (and others). Ubuntu LTSP Tour: Technical differences (between LTSP 4 and 5)