Frequently, I get errors of the following form on container start which persist until docker is restarted.

docker start e834638cd1db -- Error response from daemon: Cannot start container e834638cd1dbbc60209a772c385d5f15d8a86b8d12a96e04d077e52869555b0c: Unable to complete atomic operation, key modified

Other docker hosts which use the same consul instance as a kv store for libnetwork do not have this issue and consul continues to operate normally.