On 13 Mar 2008 at 15:43, James Tipler wrote:
Hi, I apologize if this is a stupid question – actually, I rather hope it is because if I’ve just missed something somewhere in the documentation then this should be easy to sort out.
I’ve got about 30 work stations here that are used by conferences a dozen or so 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, job’sagood’un)
This works rather nicely, but it takes a painfully long time as the FTP server 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 in the same subnet 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 get any. 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. Turned 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 - ` but that is with linux, and it might just be the difference in how windows does it. 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 created 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 to 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 50% of the 80GB drive. So, it had plenty of free space. I then have it do a local 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 network. So, thre are some things to look at. +----------------------------------------------------------+ Michael D. Setzer II - Computer Science Instructor Guam Community College Computer Center mailto:mikes@kuentos.guam.net mailto:msetzerii@gmail.com http://www.guam.net/home/mikes Guam - Where America's Day Begins +----------------------------------------------------------+ http://setiathome.berkeley.edu (Original) Number of Seti Units Returned: 19,471 Processing time: 32 years, 290 days, 12 hours, 58 minutes (Total Hours: 287,489) BOINC@HOME CREDITS SETI 4,925,706.239266 | EINSTEIN 1,464,634.787568 | ROSETTA 428,541.225917