ltsp talk
TRANSCRIPT
LTSP
Linux Terminal Server Project
Raman.PDBA
Railway Hospital,Ayanavaram,Chennai 23
What is LTSP ?The Linux Terminal Server Project
(LTSP) is a package added to Linux
that allows inexpensive thin client
computers to be connected to a
server, spreading the power of the
server to many desktops.This slide is from Jim, creator of ltsp
How does it all work ?
This slide is from Jim, creator of ltsp
Workstation Boot Methods
● Etherboot boot floppy from Rom-o-matic.net
● Etherboot Bootrom
● PXE
● Wireless ltsp booting kernel from floppy
This slide is from Jim, creator of ltsp
Boot Sequence
Send DHCP request Receive request, send reply with IP addr and name of file to download
Thin client LTSP Server
Send TFTP request for kernel
Receive request, starting sending blocks of dataStart executing kernel,
initialize devices, run /linuxrc, detect NIC, send DHCP request for more info Receive request, send reply,
including IP addr and root-path for the NFS/NBD filesystem.NFS/NBD mount
/opt/ltsp/i386 then do a Pivot root to make it the root filesystem
Grant the mount request, serve data via NFS/NBD
Run rc.sysinit, then, launch SSH connection to server,launch ldm -ltsp display manager
Receive the ssh request, allow X via ssh.
1
10
8
6
4
2
9
7
5
3
This slide is from Jim, creator of ltsp
Installing LTSP 5
Installing LTSP 5
● apt-get install ltsp-server● ltsp-build-client● Configure dhcp entries
Configuring the ServerThere are several services that need to be configured on the server.
They are:
● DHCP● TFTP● NFS● XDMCP( non ldm )
dhcpd.conf
subnet 192.168.1.0 netmask 255.255.255.0 { #range 192.168.1.20 192.168.1.250; option domain-name "example.com"; option domain-name-servers 192.168.1.1; option broadcast-address 192.168.1.255; option routers 192.168.1.1; next-server 192.168.1.108; option subnet-mask 255.255.255.0; option root-path "/opt/ltsp/i386"; if substring( option vendor-class-identifier, 0, 9 ) = "PXEClient" { filename "/ltsp/i386/pxelinux.0"; } else { filename "/ltsp/i386/nbi.img"; }}group {
use-host-decl-names on;option log-servers 192.168.1.254;
host spare{hardware ethernet 00:11:11:5f:66:46;fixed-address 192.168.1.8;filename "/ltsp/i386/pxelinux.0";}
}
/etc/xinetd.d/tftp:
service tftp{
disable = nosocket_type = dgramprotocol = udpwait = yesuser = rootserver = /usr/sbin/in.tftpdserver_args = -s /tftpboot
}
/etc/inetd.conf:
tftp dgram udp wait nobody /usr/sbin/tcpd /usr/sbin/in.tftpd -s /tftpboot
/etc/init.d/tftpd-hpa
Tftp configuration
This slide is from Jim, creator of ltsp
/etc/exports:
/opt/ltsp/i386 192.168.0.0/255.255.255.0(ro,no_root_squash,sync)
/var/opt/ltsp/swapfiles 192.168.0.0/255.255.255.0(rw,no_root_squash,async)
NFS configuration
This slide is from Jim, creator of ltsp
The display manager must be configured to accept remote connections
xdm-config:
# DisplayManager.requestPort: 0
kdmrc:
[Xdmcp]Enable=true#Port=177
gdm.conf:
[xdmcp]Enable=trueMaxSessions=100...[servers]0=/usr/bin/X11/X
XDMCP configuration?
This slide is from Jim, creator of ltsp
Workstation Configurationlts.conf
[Default]SERVER = 192.168.0.254X_MOUSE_PROTOCOL = "IMPS/2"X_MOUSE_DEVICE = "/dev/psaux"SCREEN_01 = startx
[ws001]PRINTER_0_DEVICE = "/dev/lp0"PRINTER_0_TYPE = "P"
[ws002]USE_NFS_SWAP = YSWAPFILE_SIZE = 64mSCREEN_01 = shell
[ws003]XSERVER = atiX_MODE_0 = 1600x1200
This slide is from Jim, creator of ltsp
Troubleshooting
● ltspcfg● netstat -anp● showmount -e● /var/log/messages● SCREEN_01 = shell● rpcinfo -p localhost● tcpdump & Ethereal
Our Experience
● Total Nodes: 47● Average active users 15-18● 2 LTSP server P4-1.5,2 GB RAM● Network: Assorted 100MB to Gigabyte
Switch on cat5/cat6 utp cable
Our Experience
● Clients use WindowMaker as window manager
● Single application users do not have window manager
● Custom application on Perl/Tk● Only few use OpenOffice,Browser● Local Printing
Advantages - Clients● Booting time
– under 30 secs on pxe clients Celeron/p3s– 40-50 secs on P1/P2s
● Custom print program prints on local printer, with choice to select printer.
● Roaming: Users can login anywhere in the hospital
Advantage - Sysadmin
● Single point of software maintenance● Clients are plug and play system i.e in
case of problem simply replace box, no need to install anything.
● Central monitoring of activity● Database server and LTSP server on
single switch increasing throughput and reliability.
Cost advantage
● Saves money– Lower cpu – No HDD– No FDD/CD-ROM
● Longer Lifetime. – Today's server – tomorrow's node
● Saves environment– Reduces e-waste
More Info● www.LTSP.org
● ltsp_discuss mailing list
● IRC (#ltsp on irc.freenode.net)
● www.k12ltsp.org
● www.SkoleLinux.org
● etherboot.sourceforge.net
● www.rom-o-matic.net
● www.tldp.org/HOWTO/Diskless-HOWTO.html