Re: backup strategies

From: Eric Schuele (e.schuele_at_computer.org)
Date: 10/31/05

  • Next message: Csaba Henk: "Re: backup strategies" 
    Date: Mon, 31 Oct 2005 10:32:02 -0600
To: Csaba Henk <csaba-ml@creo.hu>

    Csaba Henk wrote:
    > On Mon, Oct 31, 2005 at 09:40:16AM -0600, Eric Schuele wrote:
    >
    >>How do snapshots work and how do they provide the consistency necessary
    >>for a dump?
    >
    > [...]
    >
    >>SoftUpdates are required on the filesystem.
    >
    >
    > This sounds beautiful. I am amazed. I knew of softupdates, but they were
    > always a shady corner of my understanding of BSD.
    >
    > So live fs dumping is based on the great hackery of softupdates. Fine,
    > but in this case... shouldn't the man page make a mention of it?

    The online manual mentions it in 16.13. Wouldn't hurt for it to be in
    the man page as well.

    >
    > It just says that -L is ignored in case of unmounted/ro mounted fs-s,
    > or if there is no proper .snap dir. But it doesn't say that it will be
    > ignored if softupdates is not turned on...
    >
    > Going a bit off: which OS-es provide this live snapshot dumping
    > capability? FreeBSD? FreeBSD >= 5.x ? *BSD ? Maybe something else?

    AFAIK FreeBSD 5.0+. Other *BSD as well, i believe... but someone else
    would have to answer that.

    > (AFAIK, softupdates is supported also in other members of the BSD
    > family, yet the NetBSD dump manpage didn't have such a -L flag...)
    > 

    -- 
Regards,
Eric
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  • Next message: Csaba Henk: "Re: backup strategies"

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