Hurricane Electric's IPv6 Tunnel Broker Forums

DNS.HE.NET Topics => General Questions & Suggestions => Topic started by: dseomn on September 20, 2021, 10:24:46 AM

Title: multiple A/AAAA with dynamic updates
Post by: dseomn on September 20, 2021, 10:24:46 AM
Is there any way to have a single name with multiple A or AAAA records pointing at different places with separate dynamic updates? I tried making two separate names with separate dynamic updates, then pointing two ALIAS records from the same name to those dynamic names, but I'm only getting a single record when I look up the ALIAS name.

Dynamic records:
Code: [Select]
uriel.mandelberg.org A 300 74.104.157.60
chusuk.mandelberg.org A 300 32.212.241.128

Static records:
Code: [Select]
test123.mandelberg.org ALIAS 300 uriel.mandelberg.org
test123.mandelberg.org ALIAS 300 chusuk.mandelberg.org

Code: [Select]
$ host test123.mandelberg.org
test123.mandelberg.org has address 32.212.241.128

Is there any way to set up a name that returns records for both addresses above, where each address can be changed separately by a different dynamic dns client?
Title: Re: multiple A/AAAA with dynamic updates
Post by: snarked on September 20, 2021, 11:01:13 AM
Probably not.  The whole point of a dynamic address update is that any (and all) prior address(es) are invalid when the record is updated with a new address.  You must use separate labels to maintain more than one dynamic destination (one label per destination).  IPv4 and IPv6 dynamic addresses can coexist under a single label because they are different RR-types.

ALIAS, CNAME, and DNAME records take a single destination only.  Multiple instances of these RR-types are forbidden.

If youíre trying to do something like load balancing or failure rollover, look at SRV records if the application or protocol you intend to use supports them.
Title: Re: multiple A/AAAA with dynamic updates
Post by: dseomn on September 20, 2021, 11:47:30 AM
I thought ALIAS wasn't a real record type, so the DNS server software could do whatever it wanted to do with it? I want failover for HTTPS, so I don't think there's anything like SRV that would work for that.
Title: Re: multiple A/AAAA with dynamic updates
Post by: snarked on September 21, 2021, 10:47:24 AM
It canít hurt to add them in the hope that someday HTTP will support them, but donít hold your breath.