Q: Switching connectivity providers and root name server updates

[Chin Fang]

Barry,

Many thanks for your insight.

> 
> Even when the GTLD servers pick up the A record change, you still have the
> problem that the TTL on those glue records is 2 days.  So does it really
> make a big difference whether they pick up the change from NSI in 1 hour or
> 6 hours?  That changes the actual worst-case timeout from 49 hours to 54
> hours?

In that case, how do you see the following as a compromise?

  Instead asking our registrar to enter the IP addresses of our name
  servers in the Registry database a couple hours ahead our swing-over
  hour, we can ask our registrar to enter the new IP address info at the
  first NSI daily update (i.e. 1000 GMT or 3:00 AM PDT).  This way, the
  effect from the root server glue record TTL is shortened by 10 hours.

  If that's not enough, we can even ask our registrar to enter the new
  IP addresses into the Registry database one day ahead.

I understand doing so will cause intermittent access problems to our
site to some parties.

> What you should depend on is your off-site slave servers, whose addresses
> won't change when you switch providers.  If your ISP is operating the slave
> servers, you should arrange for both the old and new ISPs to do slave DNS
> in parallel, and have them point to both the old and new address of the
> master server (BIND allows you to put multiple addresses in the "masters"
> clause).  After you switch providers, the old ISP should pick up your
> changes, and everyone who still has their nameservers in their cache will
> get your new addresses.  Once the caches time out, everyone will start
> querying your new server or your new ISP's servers, and you can have the
> old provider remove the zone from their configuration.

Thanks for the suggestion. We were aware of this option, but didn't
pursue it in an effort to make things simple.  We will give it another
look.

Regards,

Chin Fang
fangchin at leland.stanford.edu

> 
> -- 
> Barry Margolin, barmar at genuity.net
> Genuity, Woburn, MA
> *** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to newsgroups.
> Please DON'T copy followups to me -- I'll assume it wasn't posted to the group.
>