[Info-vax] misprint or feature

[Phillip Helbig---undress to reply]

In article <4d57f5b4$1 at news.langstoeger.at>, peter at langstoeger.at (Peter
'EPLAN' LANGSTOeGER) writes: 

> In article <iikd1p$uv9$1 at online.de>, helbig at astro.multiCLOTHESvax.de (Phillip Helbig---undress to reply) writes:
> >I came across this today at a console: bootdef_dev set to dk*0.  Is this 
> >a misprint, or does it mean it will try to boot from either dka0 or 
> >dkdb0?
> 
> It is a feature. It will boot from DKA0 or DKB0 or DKC0 if you have ones.
> But usually you don't want to see this happen (eg. booting from a user disk)
> and therefor explicitely specify the system disk.
> 
> But for a multipath (SAN) system disk this could come handy, though you can
> explicitely list the devices (>>>SET BOOTDEF_DEV sysdiskpath1,sysdiskpath3)

Normally I have 2-member shadow sets, but temporarily I have a 3-member 
shadow set as the system disk on an old ALPHA.  I found that I could set 
BOOTDEF_DEV to a list of 2 physical disks, but not 3.  Of course, that's 
enough, since it just boots from one anyway and the other is for 
failover; if both are gone and only the third is left, I probably 
wouldn't want it to boot automatically anyway.