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    <div class="moz-cite-prefix">On 2016-03-30 11:56, Jonathan Tuliani
      wrote:<br>
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    <blockquote
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        <p class="MsoNormal"><span lang="EN-GB">Hi DNS Gurus,<o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span lang="EN-GB">RFC1912 recommends the
            following SOA serial number format: YYYYMMDDnn<o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span lang="EN-GB">However, this does not
            support more than 100 updates per day (whilst this sounds
            like a lot, the fluidity of the Cloud means there are some
            applications where large numbers of changes are
            commonplace).<o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span lang="EN-GB">Is there a recommended
            serial format that supports large numbers of changes?<o:p></o:p></span></p>
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    <br>
    Whatever you want? There's really no reason to maintain YYYYMMDDnn
    unless you're editing zones by hand and can't keep notes.<br>
    <br>
    I use YYYY followed by a timestamp for zones that are synthesized
    from database. I stuck with the YYYY because I had a stupid
    monitoring system that would throw errors, but it just looked for
    20[012]\d{5,} or similar. Threw out that system, but the format
    stuck until there's a reason to change it.<br>
    <br>
    The only real consideration when you're changing formats is to make
    sure that either your new format starts out generating higher serial
    numbers than you use today, or that you're ready and able to get
    your slaves to accept lower serial numbers once. If you control your
    slaves, this is trivial, but if you use a hosted solution, it may be
    more complicated.<br>
    <br>
    <pre class="moz-signature" cols="72">-- 
Dave Warren
<a class="moz-txt-link-freetext" href="http://www.hireahit.com/">http://www.hireahit.com/</a>
<a class="moz-txt-link-freetext" href="http://ca.linkedin.com/in/davejwarren">http://ca.linkedin.com/in/davejwarren</a>

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