This is a problem coming from the Index Node sporadically:
Dec 11 01:32:27 graph dockerd[775]: time="2020-12-11T01:32:27.313894086-08:00" level=error msg="[resolver] more than 1024 concurrent queries from 172.21.0.10:35758"
Dec 11 01:32:32 graph dockerd[775]: time="2020-12-11T01:32:32.376307265-08:00" level=error msg="[resolver] more than 1024 concurrent queries from 172.21.0.10:40694"
This is a problem coming from the Index Node sporadically:
Docker has a built in limitation of 1024, up from 100. It is currently not configurable: https://github.com/moby/libnetwork/issues/2214