Usually at leas one of those is present on any system
- dig
- nslookup
- host
But sometimes the usual suspects don’t work, especially in container-land. After trying them you may try some more involved/unknown things:
getent
Part of glibc, this will probably work on nearly every system.
getent hosts example.org
Or, if you specifically want to query A or AAAA records.
getent ahostsv4 example.org
getent ahostsv6 example.org
Using Python2 Or Python3
Given this depends on glibc it is more of a alternative than another real solution
python3 -c "import socket; print(socket.gethostbyname('example.org'))"
python2 -c "import socket; print(socket.gethostbyname('example.org'))"