Difference between revisions of "Ubuntu PXE Install"
(→Install services: could be Ubuntu packages either (or whatever the distro you use to server the tftp images and dhcp leases), the goal is only to give the idea) |
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=Howto= | =Howto= | ||
| − | Installing Ubuntu via PXE network boot is the way to go if you have no cd-r at hand or if you have no cdrom | + | Installing Ubuntu or Debian via PXE network boot is the way to go if you have no cd-r at hand, or if you have no cdrom drive on the machine to be installed. |
| − | |||
| − | |||
==Install services== | ==Install services== | ||
| Line 9: | Line 7: | ||
* dhcp3-server | * dhcp3-server | ||
* netkit-inetd | * netkit-inetd | ||
| + | sudo apt-get install tftpd-hpa dhcp3-server openbsd-inetd | ||
| − | + | Note: On Gutsy (7.10) and Debian Etch netkit-inetd is a "virtual package". Either inetutils-inetd or openbsd-inetd must be chosen. On one system, openbsd-inetd is already installed - the default now? | |
==Prepare your tftp server== | ==Prepare your tftp server== | ||
| Line 23: | Line 22: | ||
RUN_DAEMON="yes" | RUN_DAEMON="yes" | ||
OPTIONS="-l -s /var/lib/tftpboot" | OPTIONS="-l -s /var/lib/tftpboot" | ||
| + | |||
| + | and start the daemon via the command | ||
| + | sudo /etc/init.d/tftpd-hpa start | ||
| + | |||
| + | Verify that inetd is listening on the right port: | ||
| + | netstat -lu | ||
| + | should show | ||
| + | udp 0 0 *:tftp *:* | ||
| + | (On one Gutsy system, inetutils-inetd insisted on listening on an ipv6 socket, | ||
| + | and booting via tftp failed. Switching to openbsd-inetd solved the problem.) | ||
==Prepare your dhcp-server== | ==Prepare your dhcp-server== | ||
| − | On what interfaces should the DHCP server (dhcpd) serve DHCP requests? | + | On what network interfaces should the DHCP server (dhcpd) serve DHCP requests? |
Answer this question by editing the line in /etc/default/dhcp3-server file. | Answer this question by editing the line in /etc/default/dhcp3-server file. | ||
| − | Separate multiple interfaces with spaces, e.g. "eth0 eth1". | + | Separate multiple interfaces with spaces, e.g. "eth0 eth1". Eg: |
| − | INTERFACES="eth1 eth2" | + | |
| + | INTERFACES="eth1 eth2" | ||
| − | If you have a working dhcp server add the following lines to your group in /etc/dhcpd.conf file (or, from Feisty upward, the /etc/dhcp3/dhcpd.conf file), substituting IP and MAC address as needed | + | If you have a working dhcp server add the following lines to your group in /etc/dhcpd.conf file (or, from Etch and Feisty upward, the /etc/dhcp3/dhcpd.conf file), substituting IP and MAC address as needed. Beware not to forget the semicolons (";") at the end of lines. |
host pxeinstall { | host pxeinstall { | ||
| − | hardware ethernet [ | + | # ie. "hardware ethernet 00:0A:E4:2E:A6:42;" |
| + | hardware ethernet ''[MAC address of PXE client networkcard, without brackets]''; | ||
| + | |||
| + | # this is the unused IP address we will assign temporarily to the PXE client | ||
fixed-address 10.0.0.16; | fixed-address 10.0.0.16; | ||
| − | next-server [ip-address of the server serving tftp]; | + | |
| + | # Not needed if the tftp server is on the same host as the DHCP server. ie. "next-server 10.0.0.2;". | ||
| + | # edit : Well needed, otherwise he is looking for the host 0.0.0.0 so, it doesn't work | ||
| + | next-server [ip-address of the server serving tftp]; | ||
| + | |||
| + | # path of the bootloader file, relative to tftpd's root | ||
filename "pxelinux.0"; | filename "pxelinux.0"; | ||
} | } | ||
| − | The | + | The "next-server" stanza tells the PXE boot client where to look for the boot image and associated data. It is required in newer editions of tftpd-hpa, if not on the same machine as the DHCP server. |
| − | subnet | + | |
| − | range 192.168.0. | + | Instead, if you do not need MAC-based configuration (e.g. you want to be able to boot any host), you can just add a filename stanza to a subnet configuration (verified on Intrepid): |
| + | |||
| + | subnet 192.168.0.0 netmask 255.255.255.0 { | ||
| + | range 192.168.0.100 192.168.0.254; | ||
| + | option routers 192.168.0.1; | ||
| + | |||
| + | #substitute the DNS addresses of your own Internet Service Provider (ISP) | ||
| + | option domain-name-servers ''primary.dns.from.isp'', ''secondary.dns.from.isp''; | ||
| + | |||
filename "pxelinux.0"; | filename "pxelinux.0"; | ||
} | } | ||
| − | + | You need to assign the client an IP address in the same subnet as the address of the server running tftpd. For example, if your server's address is 192.168.'''2'''.13, you should assign your client an IP address that begins with 192.168.'''2'''.x, NOT 192.168.'''0'''.x . If your client doesn't recieve an IP-address, you might want to add '''authoritative;''' above the subnet declaration. | |
| − | ( | + | When you are done configuring your dhcp server, (re)start it: |
| + | /etc/init.d/dhcp3-server restart | ||
| − | + | And verify it runs (if not, you may have a problem in the dhcpd config file): | |
| − | |||
| − | And verify it runs (if not, you | ||
ps ax | grep dhcpd | ps ax | grep dhcpd | ||
| − | + | ==Prepare netboot files== | |
| − | + | ===Get and install the files=== | |
| − | + | All the files you need are on the install media, or you can get them from internet: | |
| + | * For Ubuntu [http://archive.ubuntu.com/ubuntu/dists/dapper/main/installer-i386/current/images/netboot/ Dapper 6.06], [http://archive.ubuntu.com/ubuntu/dists/edgy/main/installer-i386/current/images/netboot/ Edgy 6.10], [http://archive.ubuntu.com/ubuntu/dists/feisty/main/installer-i386/current/images/netboot/ Feisty 7.04], [http://archive.ubuntu.com/ubuntu/dists/gutsy/main/installer-i386/current/images/netboot/ Gutsy 7.10], [http://archive.ubuntu.com/ubuntu/dists/hardy/main/installer-i386/current/images/netboot/ Hardy 8.04], [http://archive.ubuntu.com/ubuntu/dists/intrepid/main/installer-i386/current/images/netboot/ Intrepid 8.10], [http://archive.ubuntu.com/ubuntu/dists/jaunty/main/installer-i386/current/images/netboot/ Jaunty 9.04], [http://archive.ubuntu.com/ubuntu/dists/lucid/main/installer-i386/current/images/netboot/ Lucid 10.04], [http://archive.ubuntu.com/ubuntu/dists/maverick/main/installer-i386/current/images/netboot/ Maverick 10.10]. All 32 bit (i386) files, for 64 bit files, replace installer-i386 with installer-amd64 in URLs. | ||
| + | * For Debian : [http://http.us.debian.org/debian/dists/sarge/main/installer-i386/current/images/netboot/ Sarge 3.1], [http://http.us.debian.org/debian/dists/etch/main/installer-i386/current/images/netboot/ Etch 4.0], [http://http.us.debian.org/debian/dists/lenny/main/installer-i386/current/images/netboot/ Lenny 5.0]. | ||
| − | + | Download and put the netboot directory content at the root of the tftpd's served /var/lib/tftpboot/ directory: | |
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
cd /var/lib/tftpboot/ | cd /var/lib/tftpboot/ | ||
| + | lftp -c "open http://archive.ubuntu.com/ubuntu/dists/lucid/main/installer-i386/current/images/netboot/; mirror" | ||
| + | |||
| + | # then untar the pxeboot.tar.gz (this step is NOT needed anymore, as of Feisty) | ||
tar xfz pxeboot.tar.gz | tar xfz pxeboot.tar.gz | ||
| + | |||
| + | Alternatively, if Ubuntu is in your cdrom drive: | ||
| + | mount /media/cdrom | ||
| + | cp -a /media/cdrom/install/netboot/* /var/lib/tftpboot/ | ||
===pxe bootloader config=== | ===pxe bootloader config=== | ||
| − | + | ||
| + | In the pxelinux.cfg/ directory, make a symlink named after the pxe boot client's mac address (without the colons), and pointing to the "default" config file: | ||
| + | # ie. if our client mac address is 00:0A:E4:2E:A6:42, we'll do: | ||
| + | ln -s /var/lib/tftpboot/pxelinux.cfg/default /var/lib/tftpboot/pxelinux.cfg/000AE42EA642 | ||
| + | |||
| + | For very old distros versions, you may need to edit or patch pxelinux.cfg/default . | ||
| + | This modification is NOT needed anymore (at least from Feisty or Etch and up). | ||
| + | |||
<pre> | <pre> | ||
--- default.org 2004-10-31 15:32:32.000000000 +0100 | --- default.org 2004-10-31 15:32:32.000000000 +0100 | ||
| Line 99: | Line 130: | ||
timeout 0 | timeout 0 | ||
</pre> | </pre> | ||
| − | |||
| − | |||
| − | |||
| − | |||
===Directory layout=== | ===Directory layout=== | ||
| Line 133: | Line 160: | ||
/var/lib/tftpboot/pxelinux.cfg/000AE42EA642 | /var/lib/tftpboot/pxelinux.cfg/000AE42EA642 | ||
</pre> | </pre> | ||
| + | |||
| + | In more detail we need to provide: | ||
| + | * a bootloader, which name (or path relative to tftpd's served directory, here /var/lib/tftpboot) is mentioned in the dhcpd.conf file (pxelinux.0) | ||
| + | * a configuration file for the bootloader (default for all clients, or mac specific) | ||
| + | * a kernel with an initrd file (vmlinuz,initrd.gz) | ||
| + | * an image of the base system (mini.iso) | ||
==Start the PXE client== | ==Start the PXE client== | ||
| − | Just boot up the computer that will use DHCP and then PXE to get the images, if something isn't working you can use a sniffer on your install server to check. | + | Just boot up the computer that will use DHCP and then PXE to get the images, if something isn't working you can use a sniffer on your install server to check, and look at log files for daemons misconfigurations. |
| − | + | tshark -R bootp | |
| − | + | tshark port tftp | |
| − | + | sudo tcpdump -s 1600 -neeevvvX 'proto (\udp or \tcp) and port (67 or 68 or 69)' | |
| − | + | tail /var/log/daemon.log | |
| + | |||
| + | If your network card doesn't have a PXE stack, you can try downloading a stub client from http://rom-o-matic.net/ | ||
| − | == | + | ==Optional: setup an archive mirror== |
| − | With the previous setup, Ubuntu will download install packages straight over the internet. | + | With the previous setup, Ubuntu or Debian will download install packages straight over the internet. |
| − | If you prefer to run your network installs over a private network and use your own Ubuntu mirror you can do the following: | + | If you prefer to run your network installs over a private network and use your own Ubuntu or Debian mirror you can do the following: |
| − | + | sudo apt-get install apt-mirror | |
| + | Then write an /etc/apt/mirror.list configuration file, eg.: | ||
| + | |||
| + | Example for Ubuntu dapper: | ||
<pre> | <pre> | ||
| − | set base_path / | + | set base_path /var/spool/apt-mirror/ |
deb http://gb.archive.ubuntu.com/ubuntu/ dapper main restricted | deb http://gb.archive.ubuntu.com/ubuntu/ dapper main restricted | ||
deb http://gb.archive.ubuntu.com/ubuntu/ dapper main/debian-installer | deb http://gb.archive.ubuntu.com/ubuntu/ dapper main/debian-installer | ||
| Line 154: | Line 192: | ||
</pre> | </pre> | ||
| − | + | Example for Debian Etch: | |
| + | <pre> | ||
| + | set base_path /var/spool/apt-mirror/ | ||
| + | deb http://ftp.us.debian.org/debian etch main contrib non-free | ||
| + | deb http://security.debian.org/debian-security etch/updates main contrib non-free | ||
| + | deb http://ftp.us.debian.org/debian etch main/debian-installer | ||
| + | </pre> | ||
| + | |||
| + | Then: | ||
| + | mkdir -p /var/spool/apt-mirror/{mirror,var,skel} | ||
| + | apt-mirror | ||
| − | + | This will replicate the mirror to your chosen base path. You will need to create the soft links to the dists and pool directories yourself, eg.: | |
<pre> | <pre> | ||
| − | ~$ ls -al / | + | ~$ ls -al /var/spool/apt-mirror/mirror/ |
total 24 | total 24 | ||
drwxr-xr-x 5 root root 4096 May 18 12:46 . | drwxr-xr-x 5 root root 4096 May 18 12:46 . | ||
| Line 170: | Line 218: | ||
</pre> | </pre> | ||
| − | * Serve the / | + | * Serve the /var/spool/apt-mirror/ directory out with apache |
| − | * When you boot the ubuntu network installer, point it at the | + | * When you boot the ubuntu/debian network installer, point it at the IP address and the 'mirror' directory. |
=Links= | =Links= | ||
| − | * http://wiki.ubuntu.com/ | + | * http://wiki.debian.org/PXEBootInstall a similar description in another order that facilitates debugging |
| − | * http://www. | + | * https://help.ubuntu.com/community/Installation/Netboot |
| − | + | * http://www.vercot.com/~serva/howto/UbuntuPXE1.html | |
[[Category:Infos]] | [[Category:Infos]] | ||
Latest revision as of 11:43, 1 February 2012
Contents
Howto
Installing Ubuntu or Debian via PXE network boot is the way to go if you have no cd-r at hand, or if you have no cdrom drive on the machine to be installed.
Install services
You need the following packages:
- tftpd-hpa
- dhcp3-server
- netkit-inetd
sudo apt-get install tftpd-hpa dhcp3-server openbsd-inetd
Note: On Gutsy (7.10) and Debian Etch netkit-inetd is a "virtual package". Either inetutils-inetd or openbsd-inetd must be chosen. On one system, openbsd-inetd is already installed - the default now?
Prepare your tftp server
Start your tftpd server via inetd after adding the following line in /etc/inetd.conf:
tftp dgram udp wait root /usr/sbin/in.tftpd /usr/sbin/in.tftpd -s /var/lib/tftpboot
sudo update-inetd --enable BOOT
Don't forget to create the tftp directory /var/lib/tftpboot (if it hasn't already been created)
On Ubuntu 6.06 Server and Feisty Fawn 7.04 (or if /etc/inetd.conf doesn't exist) you might edit /etc/default/tftpd-hpa:
RUN_DAEMON="yes" OPTIONS="-l -s /var/lib/tftpboot"
and start the daemon via the command
sudo /etc/init.d/tftpd-hpa start
Verify that inetd is listening on the right port:
netstat -lu
should show
udp 0 0 *:tftp *:*
(On one Gutsy system, inetutils-inetd insisted on listening on an ipv6 socket, and booting via tftp failed. Switching to openbsd-inetd solved the problem.)
Prepare your dhcp-server
On what network interfaces should the DHCP server (dhcpd) serve DHCP requests? Answer this question by editing the line in /etc/default/dhcp3-server file. Separate multiple interfaces with spaces, e.g. "eth0 eth1". Eg:
INTERFACES="eth1 eth2"
If you have a working dhcp server add the following lines to your group in /etc/dhcpd.conf file (or, from Etch and Feisty upward, the /etc/dhcp3/dhcpd.conf file), substituting IP and MAC address as needed. Beware not to forget the semicolons (";") at the end of lines.
host pxeinstall {
# ie. "hardware ethernet 00:0A:E4:2E:A6:42;"
hardware ethernet [MAC address of PXE client networkcard, without brackets];
# this is the unused IP address we will assign temporarily to the PXE client
fixed-address 10.0.0.16;
# Not needed if the tftp server is on the same host as the DHCP server. ie. "next-server 10.0.0.2;".
# edit : Well needed, otherwise he is looking for the host 0.0.0.0 so, it doesn't work
next-server [ip-address of the server serving tftp];
# path of the bootloader file, relative to tftpd's root
filename "pxelinux.0";
}
The "next-server" stanza tells the PXE boot client where to look for the boot image and associated data. It is required in newer editions of tftpd-hpa, if not on the same machine as the DHCP server.
Instead, if you do not need MAC-based configuration (e.g. you want to be able to boot any host), you can just add a filename stanza to a subnet configuration (verified on Intrepid):
subnet 192.168.0.0 netmask 255.255.255.0 {
range 192.168.0.100 192.168.0.254;
option routers 192.168.0.1;
#substitute the DNS addresses of your own Internet Service Provider (ISP)
option domain-name-servers primary.dns.from.isp, secondary.dns.from.isp;
filename "pxelinux.0";
}
You need to assign the client an IP address in the same subnet as the address of the server running tftpd. For example, if your server's address is 192.168.2.13, you should assign your client an IP address that begins with 192.168.2.x, NOT 192.168.0.x . If your client doesn't recieve an IP-address, you might want to add authoritative; above the subnet declaration.
When you are done configuring your dhcp server, (re)start it:
/etc/init.d/dhcp3-server restart
And verify it runs (if not, you may have a problem in the dhcpd config file):
ps ax | grep dhcpd
Prepare netboot files
Get and install the files
All the files you need are on the install media, or you can get them from internet:
- For Ubuntu Dapper 6.06, Edgy 6.10, Feisty 7.04, Gutsy 7.10, Hardy 8.04, Intrepid 8.10, Jaunty 9.04, Lucid 10.04, Maverick 10.10. All 32 bit (i386) files, for 64 bit files, replace installer-i386 with installer-amd64 in URLs.
- For Debian : Sarge 3.1, Etch 4.0, Lenny 5.0.
Download and put the netboot directory content at the root of the tftpd's served /var/lib/tftpboot/ directory:
cd /var/lib/tftpboot/ lftp -c "open http://archive.ubuntu.com/ubuntu/dists/lucid/main/installer-i386/current/images/netboot/; mirror" # then untar the pxeboot.tar.gz (this step is NOT needed anymore, as of Feisty) tar xfz pxeboot.tar.gz
Alternatively, if Ubuntu is in your cdrom drive:
mount /media/cdrom cp -a /media/cdrom/install/netboot/* /var/lib/tftpboot/
pxe bootloader config
In the pxelinux.cfg/ directory, make a symlink named after the pxe boot client's mac address (without the colons), and pointing to the "default" config file:
# ie. if our client mac address is 00:0A:E4:2E:A6:42, we'll do: ln -s /var/lib/tftpboot/pxelinux.cfg/default /var/lib/tftpboot/pxelinux.cfg/000AE42EA642
For very old distros versions, you may need to edit or patch pxelinux.cfg/default . This modification is NOT needed anymore (at least from Feisty or Etch and up).
--- default.org 2004-10-31 15:32:32.000000000 +0100 +++ default 2004-10-31 00:14:52.000000000 +0200 @@ -13,17 +13,11 @@ F0 debian-installer/boot-screens/f10.txt label linux - kernel debian-installer/linux - append vga=normal initrd=debian-installer/initrd.gz ramdisk_size=11057 root=/dev/rd/0 devfs=mount,dall rw -- + kernel vmlinuz + append vga=normal initrd=initrd.gz ramdisk_size=11057 root=/dev/rd/0 devfs=mount,dall rw -- label expert - kernel debian-installer/linux - append DEBCONF_PRIORITY=low vga=normal initrd=debian-installer/initrd.gz ramdisk_size=11057 root=/dev/rd/0 devfs=mount,dall rw -- -label custom - kernel debian-installer/linux - append ubuntu/install-type=custom vga=normal initrd=debian-installer/initrd.gz ramdisk_size=11057 root=/dev/rd/0 devfs=mount,dall rw -- -label custom-expert - kernel debian-installer/linux - append ubuntu/install-type=custom DEBCONF_PRIORITY=low vga=normal initrd=debian-installer/initrd.gz ramdisk_size=11057 root=/dev/rd/0 devfs=mount,dall rw -- + kernel vmlinuz + append DEBCONF_PRIORITY=low vga=normal initrd=initrd.gz ramdisk_size=11057 root=/dev/rd/0 devfs=mount,dall rw -- prompt 1 timeout 0
Directory layout
Should look like this, more or less (depending on the Ubuntu or Debian installer version used):
/var/lib/tftpboot/ /var/lib/tftpboot/pxelinux.0 /var/lib/tftpboot/initrd.gz /var/lib/tftpboot/mini.iso /var/lib/tftpboot/debian-installer /var/lib/tftpboot/debian-installer/linux /var/lib/tftpboot/debian-installer/initrd.gz /var/lib/tftpboot/debian-installer/boot-screens /var/lib/tftpboot/debian-installer/boot-screens/splash.rle /var/lib/tftpboot/debian-installer/boot-screens/f1.txt /var/lib/tftpboot/debian-installer/boot-screens/f2.txt /var/lib/tftpboot/debian-installer/boot-screens/f3.txt /var/lib/tftpboot/debian-installer/boot-screens/f4.txt /var/lib/tftpboot/debian-installer/boot-screens/f5.txt /var/lib/tftpboot/debian-installer/boot-screens/f6.txt /var/lib/tftpboot/debian-installer/boot-screens/f7.txt /var/lib/tftpboot/debian-installer/boot-screens/f8.txt /var/lib/tftpboot/debian-installer/boot-screens/f9.txt /var/lib/tftpboot/debian-installer/boot-screens/syslinux.txt /var/lib/tftpboot/debian-installer/boot-screens/f10.txt /var/lib/tftpboot/initrd.list /var/lib/tftpboot/vmlinuz /var/lib/tftpboot/pxelinux.cfg /var/lib/tftpboot/pxelinux.cfg/default /var/lib/tftpboot/pxelinux.cfg/000AE42EA642
In more detail we need to provide:
- a bootloader, which name (or path relative to tftpd's served directory, here /var/lib/tftpboot) is mentioned in the dhcpd.conf file (pxelinux.0)
- a configuration file for the bootloader (default for all clients, or mac specific)
- a kernel with an initrd file (vmlinuz,initrd.gz)
- an image of the base system (mini.iso)
Start the PXE client
Just boot up the computer that will use DHCP and then PXE to get the images, if something isn't working you can use a sniffer on your install server to check, and look at log files for daemons misconfigurations.
tshark -R bootp tshark port tftp sudo tcpdump -s 1600 -neeevvvX 'proto (\udp or \tcp) and port (67 or 68 or 69)' tail /var/log/daemon.log
If your network card doesn't have a PXE stack, you can try downloading a stub client from http://rom-o-matic.net/
Optional: setup an archive mirror
With the previous setup, Ubuntu or Debian will download install packages straight over the internet. If you prefer to run your network installs over a private network and use your own Ubuntu or Debian mirror you can do the following:
sudo apt-get install apt-mirror
Then write an /etc/apt/mirror.list configuration file, eg.:
Example for Ubuntu dapper:
set base_path /var/spool/apt-mirror/ deb http://gb.archive.ubuntu.com/ubuntu/ dapper main restricted deb http://gb.archive.ubuntu.com/ubuntu/ dapper main/debian-installer deb http://gb.archive.ubuntu.com/ubuntu/ dapper main restricted/debian-installer
Example for Debian Etch:
set base_path /var/spool/apt-mirror/ deb http://ftp.us.debian.org/debian etch main contrib non-free deb http://security.debian.org/debian-security etch/updates main contrib non-free deb http://ftp.us.debian.org/debian etch main/debian-installer
Then:
mkdir -p /var/spool/apt-mirror/{mirror,var,skel}
apt-mirror
This will replicate the mirror to your chosen base path. You will need to create the soft links to the dists and pool directories yourself, eg.:
~$ ls -al /var/spool/apt-mirror/mirror/ total 24 drwxr-xr-x 5 root root 4096 May 18 12:46 . drwxrwxrwx 11 root root 4096 May 18 12:27 .. lrwxrwxrwx 1 root root 34 May 18 12:46 dists -> gb.archive.ubuntu.com/ubuntu/dists drwxr-xr-x 3 root root 4096 May 18 12:46 gb.archive.ubuntu.com lrwxrwxrwx 1 root root 33 May 18 12:46 pool -> gb.archive.ubuntu.com/ubuntu/pool drwxr-xr-x 3 root root 4096 May 18 10:53 skel drwxr-xr-x 2 root root 8192 May 18 13:27 var
- Serve the /var/spool/apt-mirror/ directory out with apache
- When you boot the ubuntu/debian network installer, point it at the IP address and the 'mirror' directory.
Links
- http://wiki.debian.org/PXEBootInstall a similar description in another order that facilitates debugging
- https://help.ubuntu.com/community/Installation/Netboot
- http://www.vercot.com/~serva/howto/UbuntuPXE1.html
