<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Hi,<div class=""><br class=""></div><div class="">we are migrating our DNS master from BIND to PowerDNS. The approach we take is to put PowerDNS in the middle of an current replication chain as below:</div><div class=""><br class=""></div><div class="">BIND DNS master -> PowerDNS -> BIND DNS slaves</div><div class=""><br class=""></div><div class="">It works most of the time. However, from time to time we experienced long delay when making a DNS change. further investigation shows that the delay seems on PowerDNS. we see lots of errors </div><div class=""><br class=""></div><div class=""><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">2018-01-10T18:13:24.728722+01:00 pdns_server1 pdns_server</span><span class="error" style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px;">[2250]</span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">: Jan 10 18:13:24 Notification for <a href="http://example.com" class="">example.com</a> to ip1:53 failed after retries</span><br style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px;" class=""><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">2018-01-10T18:13:24.728848+01:00 </span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">pdns_server1</span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""> pdns_server</span><span class="error" style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px;">[2250]</span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">: Jan 10 18:13:24 Notification for </span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""><a href="http://example.com" class="">example.com</a></span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""> to </span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">ip2</span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">:53 failed after retries</span></div><div class=""><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">2018-01-10T18:13:24.728975+01:00 </span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">pdns_server1</span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""> pdns_server</span><span class="error" style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px;">[2250]</span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">: Jan 10 18:13:24 Notification for </span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""><a href="http://example.com" class="">example.com</a></span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""> to </span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">ip3</span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">:53 failed after retries</span></div><div class=""><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""><br class=""></span></div><div class=""><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class="">ip1,ip2,ip3 are BIND slaves.</span></div><div class=""><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 14px; background-color: rgb(245, 245, 245);" class=""><br class=""></span></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="background-color: rgb(245, 245, 245);" class=""><span style="font-size: 14px;" class="">no other errors found with regard to the root cause. it happens occasionally. Questions are:</span></span></font></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="font-size: 14px; background-color: rgb(245, 245, 245);" class=""><br class=""></span></font></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="background-color: rgb(245, 245, 245);" class=""><span style="font-size: 14px;" class="">1. Is there any rate limit as far as PowerDNS is concerned? before PowerDNS is put in the middle, there is no such delay</span></span></font></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="background-color: rgb(245, 245, 245);" class=""><span style="font-size: 14px;" class="">2. Is it configurable to set how many retries? Should PowerDNS should ensure the notifications going through rather than drop after a certain times of retry?</span></span></font></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="background-color: rgb(245, 245, 245);" class=""><span style="font-size: 14px;" class=""><br class=""></span></span></font></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="background-color: rgb(245, 245, 245);" class=""><span style="font-size: 14px;" class="">Thanks,</span></span></font></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="background-color: rgb(245, 245, 245);" class=""><span style="font-size: 14px;" class="">Steve</span></span></font></div><div class=""><font color="#333333" face="Arial, sans-serif" class=""><span style="background-color: rgb(245, 245, 245);" class=""><span style="font-size: 14px;" class=""><br class=""></span></span></font></div></body></html>