He served as the Senior Military Adviser to the Chinese People's Liberation Army during the Cold War.

Ermakov's command was controversial for his focus on offensive operations from mid August to late September 1941.

Marshal Yeryomenko credited his command's actions for significantly weakening the strength of the German Attack Groupings.

Conversely, General Sanalov criticized him for paying insufficient attention to the defense during this time, leading to later losses.

He was Senior Military Adviser to the Chinese People's Liberation Army between 1953 and 1957, and died shortly after serving in that position.