CCD Mirroring HOWTO

For those who are interested, I've uploaded a tutorial on setting up mirroring using ccd(4) to http://inglorion.net/documents/tutorials/ccd/. -- Bob

Re: CCD Mirroring HOWTO

> http://inglorion.net/documents/tutorials/ccd/ > > I have a few questions/comments about the above and about ccd > in OpenBSD in general. > > 1) You talk about "RAID only works with whole disks"? I'm curious > which RAID implementation you're referring to... it seems like you > might be talk

Re: CCD Mirroring HOWTO

> > http://inglorion.net/documents/tutorials/ccd/. > > labeling section is wrong. > one MUST never use 'c' partition. > one MUST always make an 'a' (for example) > to skip first cylinder (at least). That's true for real disks, but it doesn't seem to be true for ccd devices. If it were true, ccdco

Re: CCD Mirroring HOWTO

> >Of course, if somebody who > >actually knew the implementation details about ccd could weigh in, > >that would resolve the issue. > > they just did. > Ok, thanks for pointing that out. I apologize for my uninformed comments, especially

Re: CCD Mirroring HOWTO

On Fri, Nov 25, 2005 at 02:26:08PM +0100, mickey wrote: > On Fri, Nov 25, 2005 at 02:14:35PM +0100, Robbert Haarman wrote: > by using 'c' partition one may endup trashing real disk's label. > DO NOT USE 'c' PARTITION. Ok, I'll change the HOWTO and

Re: CCD Mirroring HOWTO

On Fri, Nov 25, 2005 at 02:43:31PM +0100, mickey wrote: > On Fri, Nov 25, 2005 at 02:41:47PM +0100, Robbert Haarman wrote: > > > > This still leaves the issue of ccdconfig setting up the c partition as > > type 4.2BSD. If this can thrash the disklabel, that sounds like a >

Re: CCD Mirroring HOWTO

On Fri, Nov 25, 2005 at 04:50:34PM +0100, mickey wrote: > default 'c' type is unused. > at least on default systems... On REAL disks, yes. On ccd disks, it seems to be different. Or maybe ccdconfig screws it up. > > 2. The OpenBSD slices of my disks start at sector 24659775. This is also > > whe

Updated CCD Mirroring HOWTO

Dear list, especially Greg and Mickey, I've updated the working copy of the CCD Mirroring HOWTO. In particular, I've split off the comparison to software RAID into a separate section and clarified that ccd does not do automatic recovery, and I've rewritten the section on labeling to state that

Re: Updated CCD Mirroring HOWTO

Dear JCR, Thank you for your informative message. > Things like "HowTo" documents, sites like openbsdsupport.org and lists > like openbsd-newbie@ are more often than not considered garbage. The > reason is simply because you are robbing the reader of the fundamental > and important details that t

Re: Updated CCD Mirroring HOWTO

Dear JCR, > To the rest of list users; Please pardon another long email from me on > this. Helping reasonable people like Robbert understand why many people > consider "HOWTO's" to be harmful is hopefully worth the added noise and > bandwidth. If this is a concern, why don't we take the discussio

Re: Updated CCD Mirroring HOWTO

Greg, Again, you raise some interesting issues. I wonder how likely the catastrophic failures you describe are, versus how likely it is that things fail in a way where ccd actually helps you. I was hoping someone else would comment on that, but that doesn't seem to have happened so far. > So