I triggered a heapdump from dynatrace, the dump file got deleted from /opt/dynatrace/oneagent/log/memorydump after about 2hrs. There is no environment AG in my installation, in this case, shouldn't the dump stay in localhost? If this is by design, where did the dump file go?
You need an AG for centralized storage of dumps but as Laura says, it is not required to trigger a dump. If you trigger one without having an AG configured for dump storage, you will have to login to the host and retrieve the dump yourself.