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Cc: freebsd-fs@freebsd.org, Pawel Jakub Dawidek <pjd@FreeBSD.org>
Subject: Re: HAST and CARP
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Thanks !


>
> When ServerB has become master and modified some data, ServerA, before setting
> to primary again, should be set to secondary to synchronize all changes and
> only after this be switched to primary, otherwise you will have split-brain
> and should synchronize full storage recreating provider on secondary.
>

I understand this idea!  and agree with you this situation.
BUT once we go into split-brain mode, there is no way to solve this 
except hastctl create xxxx.

hastctl create xxx initialize hast device and not recommend idea!! I 
agree this.

Even split-brain condition, hastctl status returns as BACKUP.

I could not find the way to resolve split-brain by script.

But managing ServerB became MASTER, that time we can change advskew to 
prevent booting ServerA keeping as BACKUP.

Of course before booting SerberA, change advskew manually! But this 
manner can not solve split-brain.

Is there any idea to solve split-brain condition?

Thanks

Hiroshi