frytoya/insurgency-sandstorm repository overview

 docker volume create insurgency

  docker run -it --restart=always --volume=insurgency:/home/inssurgency/server -p 7777:7777/tcp  -p 7777:7777/udp -p 27102:27102/tcp -p 27102:27102/udp -p 27131:27131/tcp -p 27131:27131/udp -p 27016:27016/tcp  -p 27016:27016/udp -e MAX_PLAYERS=128 -e HOSTNAME="Name of dedicated Server"  -e STEAM_TOKEN=XXXXXXXXXXXXXXXXX frytoya/insurgency-sandstorm:latest

Get another shell and Bash inside container modify with command vi.

docker ps
docker exec -it $containerid bash

     /home/server/insurgency/Config/Server/Saved/Config/LinuxServer/Engine.ini
    modify as your need
     /home/server/insurgency/Config/Server/Saved/Config/LinuxServer/Game.ini
    modify as your need