<html><head></head><body><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div>Thank you Bob for your answer.</div><div>I continued to search and saw rfc1912 page 4</div><div>It's much higher than I first thought<br></div><div><br></div>
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Le mercredi 3 janvier 2018 à 20:05:57 UTC+1, Bob Harold <rharolde@umich.edu> a écrit :
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<div><div id="yiv4848618880"><div><div dir="ltr"><div class="yiv4848618880yqt8298825979" id="yiv4848618880yqt04014"><div class="yiv4848618880gmail_extra"><br clear="none"><div class="yiv4848618880gmail_quote">On Wed, Jan 3, 2018 at 1:57 PM, Mik J via bind-users <span dir="ltr"><<a rel="nofollow" shape="rect" ymailto="mailto:bind-users@lists.isc.org" target="_blank" href="mailto:bind-users@lists.isc.org">bind-users@lists.isc.org</a>></span> wrote:<br clear="none"><blockquote class="yiv4848618880gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div>Hello,</div><div><br clear="none"></div><div>I would like to have your thoughts about what should be the best values for refresh, retry, expire and negative cache.</div><div><br clear="none"></div><div>In my case I have 2 DNS which are hosted in 2 different locations. These location are near one another (100km). The latency is very low and packet is 0.</div><div>I configured a lot of zones on my DNS and they not master for someone else.</div><div>This is a very simple setup in termes of master/slave.</div><div><br clear="none"></div><div>I would be tempted to</div><div>* configure a high refresh period since I have notify configured on the master. What about 7200s ?</div><div>* Configure a high retry period because I don't expect the master to be offline, what about 3600 ?</div><div>* configure a expire very high like 2 days so that the DNS service would work even if the master is down</div><div>* I don't have any opinion about the negative ttl yet but any advices are welcomed.</div><div><br clear="none"></div><div>What about your setups if it looks like mine ?</div><div><br clear="none"></div><div>Regards<br clear="none"></div></div></div></blockquote></div><br clear="none"></div></div><div class="yiv4848618880gmail_extra">I typically use an expire time of 14 days or a month. But that said, you need some way to get notified that zone transfers are failing.</div><div class="yiv4848618880gmail_extra">The refresh and retry are ok, but personally I would set them lower because they don't generate a lot of traffic, and a notify could get lost. It depends on how sensitive you are to extra traffic.</div><div class="yiv4848618880gmail_extra"><br clear="none"></div><div class="yiv4848618880gmail_extra">Negative TTL depends partly on how fast you want new (or accidentally deleted) records to be usable. I use 10 minutes.</div><div class="yiv4848618880gmail_extra"><br clear="none"></div><div class="yiv4848618880gmail_extra">-- </div><div class="yiv4848618880gmail_extra">Bob Harold</div><div class="yiv4848618880gmail_extra"><br clear="none"></div></div></div></div></div>
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