[sphns]

[QUOTE BY= das]
All normal boot modfiers work:

C – boot from optical media
D – boot from diagnostic partition (Apple Hardware Test) (new)
T – target disk mode
opt – a new Startup Manager
F1 or N – network boot
cmd-S – single user mode (before which an EFI console screen is briefly present)
cmd-V verbose mode

The X key does NOT boot into EFI.

[/QUOTE]

actually…

C – boot from optical media
D – boot from diagnostics on optical media if present (Apple Hardware Test) (new)
There isn’t a separate partition for this
T – target disk mode (Firewire)
opt – a new Startup Manager
F1 or N – network boot
option-n – netboot from the netboot server’s default image

cmd-s and cmd-v are both part of the OS X booter, not EFI…

[sphns]

[QUOTE BY= komakino] That kernelthread article is excellent. I can’t wait for his book to come out.

Because the Intel Macs use EFI instead of Open Firmware and EFI can’t boot Apple Partition Map formatted drives (apparently) that means that in order for a disk to be bootable it has be be formatted with a GPT partition table.

[/QUOTE]

The EFI in the Apple machines can boot Apple Partition Map formatted drives. Look at the Install DVD that ships in the box. It’s just a straight APM disc.

You can’t however, install on any partition format other than gpt. So for all intensive purposes, you have to partition your drives (internal, external Firewire or USB ) as gpt in order to install the OS.

[sphns]

$ diskutil partitiondisk
Disk Utility Tool
Usage: diskutil partitionDisk [Mount Point|Disk Identifier|Device Node]
numberOfPartitions <OS9Drivers, APMFormat, MBRFormat, GPTFormat>
<part1Format part1Name part1Size> <part2Format part2Name part2Size>
<part3Format part3Name part3Size>
(Re)Partition an existing disk. All volumes on this disk will be destroyed.
Ownership of the affected disk is required.
Format is the specific filesystem name you want to erase it as. (HFS+, etc.)
OS9Drivers specifies that an Apple Partition Map should be used, and laid
out in a manner compatible with Mac OS 9.
APMFormat specifies that an Apple Partition Map should be used.
MBRFormat specifies that the partition map should be written in DOS
compatible format.
GPTFormat specifies GUID Partitioning Scheme.

I wouldn’t recommend using the gpt tool, it doesn’t lay out the disk in the manner required by the OS (i.e. it doesn’t automatically create a ESP, which is required in order to install the OS).

[sphns]

[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.

[sphns]

On the server, you’re configuring the plist with the multicast address the data will stream over. This is not the IP address of the server itself.

A mulitcast address is either a specific address that your network admin has a range of based on your IP address, or a subnet specific address.

The 224.x.x.x. range is defined as a local multicast address range (i.e. routers should not forward mulitcast traffic). 224.0.0.123 is just an example in the man page that should work if you don’t need to multicast across routers, and it’s not in use by another service.

On the client, the IP addresss your passing in the asr:// url is the server’s IP address (or DNS name, or Bonjour name). The asr client connects to the server via TCP to fetch information, including the multicast address the data is streaming over.

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