Hadoop-services

Hadoop does not integrate well with service managers like launchd and systemd, rather relying on its own convoluted shell scripts and unsupervised ssh connections to start up things. Here I collect experimental service files for MacOS/launchd and CentOS7/systemd. The systemd/ subfolders also has a setup script to install services. The launchd scripts rely on a delay to avoid trying to bind their address before the network interface is up. This is not ideal, but I don't think launchd supports a better way. Also, Hadoop 3.x deprecates the *-daemon.sh scripts, so the systemd files will have to change eventually to accommodate that.