[AusNOG] Strange DNS issue

Heinz N ausnog at equisoft.com.au
Sun Oct 28 13:12:46 EST 2012

> Am I right in thinking it is probably that the domain had a long expire time? 
> The refresh was set to 86400, but it seems like it is being ignored or it 
> doesn't figure in how long DNS servers will wait before refreshing the 
> domain.

A few years ago I hade a similar problem when redelegating domains where 
telstra was the secondary. I had a too long refresh time and it seemed 
that their DNS only updated according to the longest number: refresh or 
retry (this is just my opinion). Everyone else's DNSs queried my 
authorative host and got the redelegations but the secondary (telstra) 
didn't for quite some time. This problem was my fault and now I have 
everything set at 1hr (except expire which is set much longer).

I resorted to adding new host A records into those domains and doing a dig 
@nsX.telstra.XXXX on those host.domain in order to force their DNS to 
re-query the zone records. This didn't trigger a zone transfer 
unfortunately, but the new hosts did then appear. I used them until the 
full zone transfer finally happened. (This is a bit difficult if your 
"www" A record is the one not updating).

PS. Don't forget to update your Zone record serial number. You might even 
try increasing it in order to try to trigger a full refresh.

Heinz N.

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