jpaulb
09-04-2006, 03:25 PM
I am sitting here on the deck with my IBM Thinkpad, looking at the lake, trying to think of something to write about wireless thin client. Since the Thinkpad is such a hog for electricity there is still a power cord connected to it, also cables connecting one USB port and the LAN port to an ASUS 330g Wireless Access Point.
I am not going into the theory of thin clients, installation, etc., Castaway did
an excellent job of that in his articles about the LTSP project. Any information
that is needed about the Thin-client can be obtained
http://www.debianquestions.com/ln-archive/viewtopic.php?t=9442&sid=afacb019e64a74b36d6651fed9bdb944
http://www.linuxagora.com/vbforum/showthread.php?t=333 and read through
the information at http://www.ltsp.org
I started to experiment with thin clients after buying a Laptop and reading
Castaways articles about the installation of LTSP. After using a laptop as a
thin client for about 6 months, the whole thought of the laptops mobility appeared to be a
joke due to a LAN cable. The newer laptops are equipped with WiFi but this is of
little value since the software to run the wireless has to be running before a
connection can be made. Since the connection has to be make before the thin
client can download the software there is a slight impasse.
So the new laptops is not really an answer. The following article started me looking for a small simple solution
http://wiki.ltsp.org/twiki/bin/view/Ltsp/WirelessClientsUsingAnEthernetBridge
I found the ASUS ethernet wireless adaptor at http://usa.asus.com/products4.aspx?l1=12&l2=41&l3=0&model=59&modelmenu=1
BEFORE ANYONE TRIES to setup this adaptor or any other, make sure that the thin client is working on a LAN cable!!!!!!
Getting the adaptor to work.
Set the switch on the back to Ethernet Adaptor NOT Access Point
Plug the adaptor into a working box, USB connection and LAN.
The adaptor IP is factory set at 192.168.1.1 this has to be changed to match your network. My case 192.168.0.4, the next free slot I use for routers.
Setup is straight forward, enable MAC cloning this eliminates adding the MAC address of the adaptor to the dhcpd.conf file.
For each thin client I have setup its own file in /tftpboot/lts/2.6.17.8-ltsp-1/pxelinux.cfg, the name being the hex value of the ip address eg 192.168.0.101 is C0A80065
When you boot the thin client there will probably be a waring
nfs warning:server not responding
and the boot process is even longer than windozes XP
Don't panic. read http://wiki.ltsp.org/twiki/bin/view/Ltsp/NFS
The problem is caused by the 2.6 kernels using a large default blocksize for
NFS packets. The 2.6 kernels use 32k blocks, where the older kernels used 8k
blocks. What happens is the 32k byte blocks need to be broken down into 1500A
byte datagrams. Simple math will tell you that you need a whole lot more 1500
byte datagrams to make up a full 32kbyte block. Sending those datagrams to a
10mbit card takes too long for all of the datagrams to get there, so the NFS
client times out before getting all of the fragments.
Solution add MOPTS=nolock,ro,wsize=2048,rsize=2048 to your config file in /tftpboot/lts/2.6.17.8-ltsp-1/pxelinux.cfg
mine looks so:
******************************************
prompt 0
label linux
kernel bzImage-2.6.17.8-ltsp-1
append rw root=/dev/ram0 initrd=initramfs.gz MOPTS=nolock,ro,wsize=2048,rsize=2048, vga=773 *******************************************
The vga=773 is not necessary, it is used here to change the screen so I know I
am working with the correct file. There is nothing worse than spending hours
modifying the wrong file.
If every thing is setup properly you should be able to boot the thin client.
Maybe not.
The Asus Adaptor when connected to the USB port does not power up until the
laptop is turned on, the adaptor requires some time to boot and make a
connection with the WiFi router. This could cause the boot sequence to time out.
I have set the boot sequence so that the last to boot is the Hard drive and
the netboot just before that. This gives me a little more time incase the
adaptor is slow to get on line.
I am not going into the theory of thin clients, installation, etc., Castaway did
an excellent job of that in his articles about the LTSP project. Any information
that is needed about the Thin-client can be obtained
http://www.debianquestions.com/ln-archive/viewtopic.php?t=9442&sid=afacb019e64a74b36d6651fed9bdb944
http://www.linuxagora.com/vbforum/showthread.php?t=333 and read through
the information at http://www.ltsp.org
I started to experiment with thin clients after buying a Laptop and reading
Castaways articles about the installation of LTSP. After using a laptop as a
thin client for about 6 months, the whole thought of the laptops mobility appeared to be a
joke due to a LAN cable. The newer laptops are equipped with WiFi but this is of
little value since the software to run the wireless has to be running before a
connection can be made. Since the connection has to be make before the thin
client can download the software there is a slight impasse.
So the new laptops is not really an answer. The following article started me looking for a small simple solution
http://wiki.ltsp.org/twiki/bin/view/Ltsp/WirelessClientsUsingAnEthernetBridge
I found the ASUS ethernet wireless adaptor at http://usa.asus.com/products4.aspx?l1=12&l2=41&l3=0&model=59&modelmenu=1
BEFORE ANYONE TRIES to setup this adaptor or any other, make sure that the thin client is working on a LAN cable!!!!!!
Getting the adaptor to work.
Set the switch on the back to Ethernet Adaptor NOT Access Point
Plug the adaptor into a working box, USB connection and LAN.
The adaptor IP is factory set at 192.168.1.1 this has to be changed to match your network. My case 192.168.0.4, the next free slot I use for routers.
Setup is straight forward, enable MAC cloning this eliminates adding the MAC address of the adaptor to the dhcpd.conf file.
For each thin client I have setup its own file in /tftpboot/lts/2.6.17.8-ltsp-1/pxelinux.cfg, the name being the hex value of the ip address eg 192.168.0.101 is C0A80065
When you boot the thin client there will probably be a waring
nfs warning:server not responding
and the boot process is even longer than windozes XP
Don't panic. read http://wiki.ltsp.org/twiki/bin/view/Ltsp/NFS
The problem is caused by the 2.6 kernels using a large default blocksize for
NFS packets. The 2.6 kernels use 32k blocks, where the older kernels used 8k
blocks. What happens is the 32k byte blocks need to be broken down into 1500A
byte datagrams. Simple math will tell you that you need a whole lot more 1500
byte datagrams to make up a full 32kbyte block. Sending those datagrams to a
10mbit card takes too long for all of the datagrams to get there, so the NFS
client times out before getting all of the fragments.
Solution add MOPTS=nolock,ro,wsize=2048,rsize=2048 to your config file in /tftpboot/lts/2.6.17.8-ltsp-1/pxelinux.cfg
mine looks so:
******************************************
prompt 0
label linux
kernel bzImage-2.6.17.8-ltsp-1
append rw root=/dev/ram0 initrd=initramfs.gz MOPTS=nolock,ro,wsize=2048,rsize=2048, vga=773 *******************************************
The vga=773 is not necessary, it is used here to change the screen so I know I
am working with the correct file. There is nothing worse than spending hours
modifying the wrong file.
If every thing is setup properly you should be able to boot the thin client.
Maybe not.
The Asus Adaptor when connected to the USB port does not power up until the
laptop is turned on, the adaptor requires some time to boot and make a
connection with the WiFi router. This could cause the boot sequence to time out.
I have set the boot sequence so that the last to boot is the Hard drive and
the netboot just before that. This gives me a little more time incase the
adaptor is slow to get on line.