pkg.AZTCO-FW.org Has no A/AAAA Record

pkg does not use A/AAAA records. It uses service (SRV) records. The update server meta names such as pkg. AZTCO-FW.org are not meant to be accessed directly using a browser.

To find the actual update servers, lookup the SRV record for the host

$ host -t srv _https._tcp.pkg.AZTCO-FW.org
_https._tcp.pkg.AZTCO-FW.org has SRV record 10 10 443 files01.netgate.com.
_https._tcp.pkg.AZTCO-FW.org has SRV record 10 10 443 files00.netgate.com.
 
$ host files01.netgate.com. files01.netgate.com has address 162.208.119.40
files01.netgate.com has IPv6 address 2610:1c1:0:6::40
 
$ host files00.netgate.com. files00.netgate.com has address 162.208.119.41
files00.netgate.com has IPv6 address 2610:1c1:0:6::41

Accessing the hosts using their real hostnames will work with a browser:

$ curl –output /dev/null –silent –head –fail \
“https://files00.netgate.com/AZTCO-FW_v2_4_5_amd64-core/meta.txz”
$ echo $?
0