ubuntu ltsp clients boot problem exiting pxe-rom

it is sometimes ltsp clients might not boot properly
exiting the pxe-rom

to fix the bug

run this commands as root or sudo

#service dnsmasq restart

#service tftpd-hpa restart

if ltsp server ip is changed then run

# ltsp-update-kernels

# ltsp-update-sshkeys

# ltsp-update-image


#sed -i 's/ipappend 2/ipappend 3/g' /var/lib/tftpboot/ltsp/****/pxelinux.cfg/default

where **** is amd64 or i386 depends upon arch 

it is better put these commands in /etc/rc.local to make automated while booting.

LTSP on ubuntu 14.04 virtual environment


i give outline of how to LTSP  on ubuntu 14.04 in virtual environment (virtual box)

i refer two sites for this

1. how to configure LTSP server in ubuntu 14.04

detailed explanation give in the forum

1. Let's install LTSP, a proxy DHCP server, and a TFTP server:

# sudo apt-get install ltsp-server dnsmasq tftpd-hpa

 Dnsmasq can do both DHCP and TFTP,  it has a bug when functioning
 as a TFTP server specifically with Ubuntu 14.04, so we use  tftpd-hpa for that

2. install the client image

for 64 bit architecture,
# sudo ltsp-build-client

for 32 bit systems,
# sudo ltsp-build-client --arch i386

The configuration file for our PXELINUX is under /var/lib/tftpboot/ltsp/****/pxelinux.cfg/default

****  for 32 bit systems use i386 , for 64 bit systems use amd64.

The  version of LTSP included in Ubuntu 14.04 and 12.04,  is generated without support for proxy DHCP by default. To fix this, you must run:

for ubuntu 14.04,

3. # sudo sed -i 's/ipappend 2/ipappend 3/g' /var/lib/tftpboot/ltsp/****/pxelinux.cfg/default

****  for 32 bit systems use i386 , for 64 bit systems use amd64.

documentation for 'ipappend' can be found here

4. To configure Dnsmasq. create a file  'vim   /etc/dnsmasq.d/ltsp.conf'
   and put exactly like this
# Dnsmasq running as a proxy DHCP and TFTP server
# See:


# This might work instead of tftpd-hpa:


# DHCP proxy on this network

# Tell PXE clients not to use multicast discovery
# See section in

# Better support for old or broken DHCP clients

# Enable this for better debugging


# Note the file paths are relative to our "tftp-root" and that ".0" will be appended

pxe-prompt="Press F8 for boot menu", 3
pxe-service=x86PC, "Boot from network", /ltsp/i386/pxelinux
pxe-service=x86PC, "Boot from local hard disk"

5 .restart the dnsmasq server

# sudo service dnsmasq restart

LTSP on Ubuntu uses an ssh tunnel for secure X forwarding, but you can switch to "direct X" mode for better scalability and performance. we have to create this file

6.  vim /var/lib/tftpboot/ltsp/****/lts.conf

**** - i386 / amd64

7. Now we need to regenerate the image and not forget to fix the proxy DHCP issue

   for ubuntu 14.04,

# sudo ltsp-update-image

# sudo sed -i 's/ipappend 2/ipappend 3/g' /var/lib/tftpboot/ltsp/****/pxelinux.cfg/default

**** - i386 / amd64

restart the server thats it LTSP server is ready.

Configure the LTSP client in virtual environment

i refer the site

as usual create a new virtual machine with 
give the name for vitual machine
fix the RAM size
in the hard drive wizard ' do not add a virtual hard drive'

warning message pops, but you can continue

go for the selected ltsp client virtual machine  settings
go for systems tab, in motherboard tab make boot order  box
network option to top check this and uncheck other things.
check enable I/O APIC , hardware clock in UTC time.
make pointing device to ps/2 mouse

go for network settings , enable the network adapter
attached to bridged adapter,
go for advanced
make adapter type to PCnet-FAST 111 (AM79C973)
make promiscuous mode to allow all then give OK.

start the ltsp client machine, it asks for select start up disk
just give cancel options. it search for network boot from the LTSP
image created in the LTSP server.

The LTSP client boots now.



dell inspiron 15 3000 series wifi drive for ubuntu 14.04


first lets know the information about pci buses connected to the laptop

# lspci

from that know the wifi adapter model

adapter model  BCM 43142

search for the wireless driver for BCM wifi adapter for ubuntu 14.04

i refer from

give the command

# sudo apt-get install linux-headers-`uname -r` dkms build-essential bcmwl-kernel-source

thats it ! available wifi connections are shown in the applet.

Install and Configure LAMP in CentOS Server

Here's setting up LAMP Stack in CentOS

we need Apache, MySql and PHP to be installed

we will see step by step on it

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