Tuning / triming for boot.wim?

hello all -

I was curious if there are options within OSD to help process the boot.wim during the pxe imaging process, to make it go faster? Are there settings/configurations I can tune, or ways to delete anything that might be obsolete that is making it larger/take longer to process?

any feedback here? it takes a really long time for our boot.wim to process after selecting our image from the pxe screen. curious if I am the only one, or if some optimization options are available?

IIRC, the boot.wim is downloaded via TFTP and the performance can be affected by the TFTP Block Size. There are two places to configure the TFTP Block Size. I believe the one exposed in the OSD Web Interface affects the transfers up to starting the Windows Boot Manager (so, basically, just getting as far as the rembo menu on the client, I think.) Then there’s a second TFTP Block Size option used by the Windows Boot Manager to download the boot.wim file; I believe this one can be configured by a task in the OS Deployment and Bare Metal Imaging site, look for fixlets/tasks with TFTP in the name.
The actual value that’s optimum depends on your specific network, how many hops to the client, MTU sizes, and expectation for dropped packets. I’ll try to lookup my value next week, but I think that at least 1434 bytes is good for matching Ethernet MTU size and you should go at that size or larger (and in multiples of 1434 assuming Ethernet with MTU 1500 bytes). I’ll correct this post next week if that’s the wrong value.

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nice, thanks. the first one loads pretty quickly (getting to the menu), it’s the second that is grabbing the boot.wim file that is terribly slow. I see the task you are referring to, would be interesting to hear what yours is set to. this gives me something to investigate and research further, much appreciated!