Re: Hosting Another IHE's Web Services in the Event of a Disaster

[John Kaftan <jkaftan () UTICA EDU>]

I tried to get a secondary DNS setup offsite but our DNS guy shot it down.
He said that the Tier1 DNS providers force an extended TTL to save traffic
and cycles on their DNS servers.  Therefore no matter what you set your TTL
to some folks will not be able to get to your backup site for an extended
period of time.

Has anyone experienced this?

I am looking to do this anyway in the near future as we are going to switch
ISPs soon and I want to ease the pain of re-numbering.



-----Original Message-----
From: Valdis Kletnieks [mailto:Valdis.Kletnieks () VT EDU]
Sent: Friday, October 20, 2006 6:48 PM
To: SECURITY () LISTSERV EDUCAUSE EDU
Subject: Re: [SECURITY] Hosting Another IHE's Web Services in the Event of a
Disaster

On Fri, 20 Oct 2006 16:22:15 CDT, Harry Flowers said:
> We're doing that with another university in our state system that's
> about 200 miles away.  To answer the additional question about DNS, we
> have a secondary at yet a different university in a different state.  At
> the minimum, you'd want a secondary at your host site if nowhere else.
> In the event of an emergency where none of your services were available,
> you'd need to have someone edit the secondary manually to change the IP
> address for you primary web server.

The part people who do this *always* manage to forget is to publish the DNS
entries with a low enough TTL to matter - if www.yourschool.edu has a 5-day
TTL
on it, it's likely going to be several days before some places notice.