haven’t tried it, but reading the man page is informative…. two interesting new asr variations:

asr -source source -server configuration [options]
asr -source asr://source -file file [options]

Multicast server:
asr -source -server

Will start up a multicast server for the specified image, using the
parameters in the configuration.plist. The image will not start multicas-
ting on the network until a client attempts to start a restore. The
server will continue to multicast the image until the process is termi-
nated.

An example multicast configuration file:
defaults write /tmp/streamconfig “Data Rate” -int 6000000
defaults write /tmp/streamconfig “Multicast Address” 224.0.0.123
(will create the file /tmp/streamconfig.plist)

Multicast client
sudo asr -source asr:// -target -erase

Multicast client restoring to a file
sudo asr -source asr:// -file -erase
Will receive the multicast stream from and save it to a file.
If is a directory, the image of the streamed disk image will be
used the save the file. -erase causes any existing file with the same

Greetings,
I have been trying to get this to work in my test environment before I unleash this on the network. I am behind a Linksys router. I also have DNS running as I have test Windows 2003 domain controllers. Anyway, I am a bit fuzzy with the settings. I am assuming that the Multicast Address is the address of the server that will be broadcasting, in my case 192.168.0.10? If so, when I add that to the .plist, and then run the ASR Multicast Server, I get the following:

Multicast server configuration:
Multicast Address: 192.168.0.10
Data Rate: 6000000
DNS Service Discovery: false
Ignoring bad URL
Ignoring bad URL
Ignoring bad URL

The Ignoring bad URL repeats its self over and over until I kill it. If I replace the 192.168.0.10 with the DNS name: od.adtest.usb.edu I get this:

Multicast server configuration:
Multicast Address: od.adtest.usb.edu
Data Rate: 6000000
DNS Service Discovery: false
Usage:
    asr -h | -v
    asr -source <source> -target <target> [<options>]
    asr -source asr://<host>/ -file <file> [<options>]

I know this is new and all, but the man page does not provide much info except on how to use it. Any help would be appreciated.

Sincerely,

Andrew

—————————————————–

Andrew W. Johnson
Instructional Support Assistant
Department of Instructional Computing
Division of Information Technology
Stony Brook University
Melville Main Library, Room S1464
Stony Brook, NY 11794-3350
Tel: (631) 632-1824
Cell: (631) 767-9946

[QUOTE BY= mkalien] I’m glad you got it working. I haven’t tried it yet, but was going to today. Does anyone have any resources on what all is going on when you use the asr:// URL? If I run asr -source asr:// on 10 macs around the same time, I’m assuming they will all get the same multicast stream, but how do I know? What if I start one and then another 5 minutes later with the same asr:// URL? [/QUOTE]

asr set up as a server is doing two things:

-It’s listening on a TCP port for clients that want to join. When a client starts, it connects to the server, and gets back some metadata about the image being streamed, and other info such as the multicast address of the stream.

-Once a client has requested the above metadata, the server starts streaming the disk image on the specified multicast address.

At that point, any and all clients will be joining the same multicast stream. Clients don’t (and can’t really) join at the same time. When a client is started, it just ‘jumps in’ wherever the stream is and starts restoring from that point, wrapping around until it gets all the blocks of the disk image file. So to your question above, if you started a client against a specific server, and 5 minutes later you started more clients, they simply start restoring the disk image from the point they join the stream. the first client will finish when the server has streamed the disk image file, and the other clients will finish on the 2nd pass of the server streaming the file. That’s why the server just keeps streaming the file over and over. It has no idea of how many clients are reading the stream*, nor when they are going to finish. It’s important to not stop the server until you know all the clients have finished.

So other than the startup metadata request, the server can ‘handle’ an unlimited number of clients, because they are all just reading the same multicast stream.

*Yes, the server could keep track of what clients have joined based on them asking for their initial metadata, but it currently doesn’t.

I got it to work finally. I guess rushing through things never works right, even though the error message is a bit misleading. I basically had not scanned the image for multicasting. One I recreated it and scanned it for multicasting it seemed to work. It seems it NetRestore Helper scans for ASR and Multicasting or something like that. Now all I have to do is play with the data rates. My test computer is a very old G4, but most of the computers I have out in our labs are High end G4-G5s.

Thanks for the suggestions.

Andrew

Can anybody post some performance results using this method??

Our image is 12Gb.. and we have about 1000 ibooks to image. We have a Xserve running Tiger, and right now the “tiger solution” is killing us @ 4 hours per machine. Running about 6-8 simultaneously. We’ll be dropping in a gigabit switch when it arrives.

In the X.3 era with Mr bombich at our side, we could crank 200 a day.

Oh.. to be on the bleeding edge of teknowledgie

TIA
M_T