One of several eruption-related problems this article mentions is the lost of electrical power:

“Also, around 27,000 residences in Kumamoto and Oita prefectures suffered a brief power outage, which was believed to have been caused by falling ash.”

– Kirk

http://www.japantimes.co.jp/news/2016/10/09/national/quakes-kumamoto-tourism-industry-takes-another-hit-eruption-mount-aso/