Cloudflare’s 1.1.1.1 seems to be having trouble with disa.mil names and dnssec; Cloudflare doesn’t work and Google’s 8.8.8.8 does.
$ dig disa.mil @8.8.8.8 +dnssec +short
156.112.108.76
A 8 2 7200 20181117145327 20181018145327 52983 disa.mil.
dMS5WbQ5xJ0HuCBPZUkuoshf0A2n1tvxA75smhcFZNS5SHSOA0zsQaSc
YOzNdu5gH6qFXA7TbKhPYN0RcPD+vVcmtfbzv3eJZfh4343IXlBznG6w
aLaLt+kI6GGnPQ7skNWOcO4yLct+yaeNxTT95CZnHtwRUx3vzGHS3dJF GYc=
$ dig disa.mil @1.1.1.1 +dnssec +short
156.112.108.76
Note that 1.1.1.1 didn’t return dnssec data. When using a client that enforces dnssec, that leads to an inability to resolve the name.
Since Google returns DNSSEC data, I’m assuming disa.mil’s DNSSEC is valid and working.