---------------

Chris Hoogendyk

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  O__  ---- Systems Administrator
 c/ /'_ --- Biology & Geology Departments
(*) \(*) -- 140 Morrill Science Center

<hoogendyk AT bio.umass DOT edu>

Erdös 4




liang cao wrote:

thank you for answering my questions

but if there is only one directory (even only one file) I want to backup (set the dumpcycle 7days), will amanda divide the file into 7 parts ?

and If the data which is been backed up is changed,what will amanda do?

2009/8/5, Chris Hoogendyk <hoogendyk AT bio.umass DOT edu <mailto:hoogendyk AT bio.umass DOT edu>>:

    liang cao wrote:

        hello
        I have read some documents about amanda.I don't understand
        that at least one full backup within 7days(if I set dumpcycle
        7 days).Is it a real full backup?
        For example,I have directories
        (home1,home2,home3,home4,home5,home6,home7) and the dumpcycle
        is 7 days.As the documents said,amanda will perform a full
        dump of 1/7th
         of all file systems each day, and perform incremental dumps
        on the rest of the 6/7th of file systems.
        If the day is first day(monday) of the first week,first day to
        use amanda,does that mean no incremental dumps on the day ?
        Suppose that I want to recover all of my data on tuesday of
        the second week,will amanda use the dump image in the first week ?
        Suppose that home1 is full backed up on monday,but the full
        back up of home1 has been destroyed,does that mean the after 6
        days' dump images can't be used(because they only have the
        incremental dumps,it's useless if we don't have the full dump)?
        In a word ,I can't understand how to recover the data if
        amanda use a different backup scheduling.
        Could you describe the exact processes of recovering or give
        me a document ?
        If the data which is dumping is changed,what will amanda do?
        My mother tongue is not English,wish that you could understand
        my meaning.
        thank you!


    You seem to be doing just fine with your English.

    When you first ask Amanda to back up a particular directory, it
    will necessarily do a full backup. As you say, it cannot do an
    incremental until it first has a full. Because of this, in a new
    installation, it may be a good idea to add a few directories each
    day until they are all added to the configuration. Of course, that
    depends in part on how large the amount of data in all those
    directories is in relation to your backup resources (size of
    tapes, network bandwidth, server capabilities, disk space for
    virtual tapes, etc.)

    I would suggest that you have a tape cycle at least twice your
    dump cycle, preferably even more. This would ensure that your full
    backups don't get overwritten until you have at least one more
    cycle of full backups. More redundancy is always better with backups.

    Amanda handles the recovery and tells you what tapes it needs (or
    recovers from appropriate virtual tapes). From it's indexes, it
    knows what full backup to refer back to and which incremental
    backups should be applied as well. For example, if I ask Amanda to
    recover home2 to its state on August 1, 2009, Amanda will look for
    the first full backup on or before that date. It will also look
    for incremental backups between the full backup and August 1. Then
    it will inform me what it needs. Finally it will proceed to get
    the full backup recovered and then to get the incremental backups
    recovered and apply them to that.

    I hope that makes sense.

    Good luck. Make use of the wiki -- http://wiki.zmanda.com
    <http://wiki.zmanda.com/>, and ask the list if you need more help.

-- Chris Hoogendyk