On Sat, 17 Dec 2005 18:03:21 +0100, Martin Reindl <[EMAIL PROTECTED]> wrote:
>"J.C. Roberts" <[EMAIL PROTECTED]> wrote: > >> On Fri, 16 Dec 2005 13:50:48 -0800, "J.C. Roberts" <[EMAIL PROTECTED]> >> wrote: >> >> >(2) When doing the installation disklabel, the "suggested" starting >> >offset for the 'a' partition is 0? I know using an offset of 0 is >> >discouraged on i386 and other systems (default is 63), so I figured I'd >> >ask if using a 0 offset is the "best/correct" way for alpha? >> >> Just for those searching the misc@ archives... >> >> I received info off-list that disklabel is doing the right thing by >> using an offset of 0 on the alpha architecture. > >I wonder anyway how you got the impression it was doing wrong and the >offset would be 63 for the first slice. FAQ 14.1 only talks about i386 >and amd64 under 'Disklabel tricks and tips/Leave first track free'. >It's clear imo. There's a difference between thinking disklabel is doing the wrong thing and just making sure it's doing the right thing. ;-) The alpha PSW is a weird beast with it's "Dual BIOS" where the first AlphaBIOS/ARC is for running WinNT4 with x86 BIOS emulation support and the second, the SRM Console, is for running Tru64 and OpenVMS. The guys I've talked to at Digital/Compaq/HP told me the multitude of alpha SRM's are very much closed source (due to the fact they control VMS licensing/revenue) and obviously, each SRM is specifically built for each machine model. On the weird machines like the PSW where multi/dual-booting NT, VMS and OSF/1 can be done, there *might* be some mad hackery in this particular SRM with a requirement for keeping the first (logical) track free for the MBR. >From what I've read, I think the way the linux guys have hacked a way into supporting the use of AlphaBIOS/ARC on the PSW is by having the MBR and a small FAT partition for lilo and such. This same approach is used on the PSW when running WinNT4 with NTFS. In a situation where you are *only* running OpenBSD, using a offset of 0 is probably just fine. On the other hand, if you happen to have WinNT installed someplace (i.e. installed on another disk), the supposedly "harmless" tag that NT writes on all disks might make a real mess of your OBSD install. The problem is not so much that the OpenBSD docs are unclear, instead, the problem is the setup of particular machine, particularly in muti-boot configs, can be very convoluted. I only asked because I'm just trying to *understand* what the heck I'm doing and what all the possible ramifications are. -In other words, curiosity. ;-) kind regards, jcr
