See no peers for some torrent(s)? Add more tracker(s) from Transmission
cd directory where Dockerfile docker build -t transmission-tracker-add:latest . or take image docker pull andrewmhub/transmission-tracker-add
docker run --net=host -d -e HOSTPORT=localhost:9091 -e TR_AUTH=user:password --name=transmission-tracker-add andrewmhub/transmission-tracker-add:latest
Don't be confused with failed message. In most cases, it means tracker(s) already added and/or exists in current torrent.