Thanks for replying so fast!
Actually, you're point about the switch is spot on. It's a 3com, and
spending a few minutes poking around in it's config last night sorted
everything out - should have checked it before posting here really!
From: Michael D. Setzer II [mailto:firstname.lastname@example.org]
Sent: 13 March 2008 22:49
To: James Tipler; udpcast(a)udpcast.linux.lu
Subject: Re: [Udpcast] newbie questions:
On 13 Mar 2008 at 15:43, James Tipler wrote:
Hi, I apologize if this is a stupid question - actually, I rather hope it
because if I've just missed
something somewhere in the documentation then this
should be easy to sort
I've got about 30 work stations here that are used by conferences a dozen
times a year.
Each time they come in they manage to make a mess of
them in one way or
another, so each
workstation gets re-imaged once they've gone away.
Currently, we do this
with a little linux
partition with G4L on it and a little tweaking of the
Windows NT boot
loader. (Basically, run batch
file in windows - machine goes down, linux comes up,
script runs, disk
image.gz is pulled from
FTP server and written to the windows partition,
machine goes down,
windows comes up,
This works rather nicely, but it takes a painfully long time as the FTP
struggles under the
load of 30 connections. UDP-cast looks perfect for
solving this problem,
but I can't seem to make
it work. This is the command I've got:
(from the FTP server -windows 2003 machine)
Udp-sender.exe -file c:\bootfiles\image.gz
(from the client machines linux command line)
Udp-receiver -pipe "gzip -dc" -file /dev/sda1
The network infrastructure is very simple. All the machines involved are
129.67.50.xx (in fact they're all on the same
switch to try and keep this
as fast as possible)
The UDP sender starts to run and awaits connections, but never seems to
The UDP receivers sit and wait for a control
connection from the server,
but never get any either.
What am I doing wrong?
Not a 100% sure? But here are some things.
First off, what kind of switch do you have? I had no problems with my old
hubs, then MIS replaced them with 3COM switches, and udpcast stopped
working. It would work with a single set of machine, but not multiple.
out to be an IGMP setting if I recall correctly.
Second, what does it say exactly it show on the sender and reciever screens
concerning the multicast-
G4L does have the option to receive udpcast, and checking the lines, with
lzop compression it is `lzop -d -c -` and with gzip it shows `gzip -c - `
that is with linux, and it might just be the difference in how windows does
So, it could just be the missing -.
Being the mainter of G4L, it make use of udpcast every week. I generally
make updates to my lab machines, and create a new g4l backup image, and
the use udpcast to image all the other machines in the lab. So, one ftp
download to a sinfle machine, and then multi-cast to all the others. I
a custome udpcast send disk, and 7 copies of a udp-recieve disk. Just put
the sender disk in the one machine, and it has all options set, and is ready
go. Then boot other machines from the reciever disk, and then hit enter on
any machine went all are ready. I setup these CDs to do a whole disk image,
so no inputed needed at all. Works just great.
Another options. In my lab, the XP partition is always get messed up or
changes, and we were recently getting this kavo virus being spread by
flahes, and Norton was not stopping it at all. In this case, my XP partition
imagge is about 6GB, so I just copied it to the Linux partition, which is
of the 80GB drive. So, it had plenty of free space. I then have it do a
ntfsclone restore to the XP partition, and can reimage the windows in about
10 minutes. NTFSCLONE is faster, since it only copies used data, and by
not downloadin the image to all machines at once puts no load on the
So, thre are some things to look at.
Michael D. Setzer II - Computer Science Instructor
Guam Community College Computer Center
Guam - Where America's Day Begins
Number of Seti Units Returned: 19,471
Processing time: 32 years, 290 days, 12 hours, 58 minutes
(Total Hours: 287,489)
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