[Pdns-users] PDNS recursive problem - NXDOMAIN - CNAME resolving

[Mislav | SysAdmin]

Hi. I've noticed some problems with CNAME resolving on our pdns server. 
Here is the example:
> $ nslookup mobile-universe.ch ns1.private.ch
> Server:        ns1.private.ch
> Address:    private#53
>
> Non-authoritative answer:
> Name:    mobile-universe.ch
> Address: 18.194.35.161
>
> $ nslookup www.mobile-universe.ch ns1.private.ch
> Server:        ns1.private.ch
> Address:    private#53
>
> ** server can't find www.mobile-universe.ch: NXDOMAIN

As you can see, without-www it works, but that record is A record. 
However, www record doesn't work,
because it resolves to some AWS CNAME record.

For example, dig works:
$ dig +short www.mobile-universe.ch @ns1.private.ch
elb-front-92-10-617833872.eu-central-1.elb.amazonaws.com.

I did some research and it could be also that this AWS IP is not 
resolve-able, but I don't remember the dig flags to check this.
But if you do directly dig on this amazon CNAME, it returns two IPs, so 
it might be powerdns problem after all? Can somebody
check this and confirm is it problem pdns recursor or aws broken dns?

I also took some CH IP from https://public-dns.info/nameserver/ch.html
> $ nslookup www.mobile-universe.ch 83.97.124.225
> Server:        83.97.124.225
> Address:    83.97.124.225#53
>
> Non-authoritative answer:
> www.mobile-universe.ch    canonical name = 
> elb-front-92-10-617833872.eu-central-1.elb.amazonaws.com.
> Name:    elb-front-92-10-617833872.eu-central-1.elb.amazonaws.com
> Address: 52.58.17.141
> Name:    elb-front-92-10-617833872.eu-central-1.elb.amazonaws.com
> Address: 52.57.147.203
So their nslookup can resolve this, but my powerdns can't. Thoughts how 
to debug this?