Dynamips (Cisco router emulator) ready Docker container.
You can run below command to start emulator
docker-compose run dynamips
or
docker run -it -v c1700-adventerprisek9-mz.124-15.T8.bin:/c1700-adventerprisek9-mz.124-15.T8.bin:ro ichikawayukko/dynamips:v0.2.21-alpine -P 1700 -o 64 -r 128 c1700-adventerprisek9-mz.124-15.T8.bin
This Docker image does not contain Cisco IOS. So, please DO NOT forget change image filename as your own IOS.
You should use docker-compose run instead of docker-compose up for better UI experience.