If you want to find out the uptime or load average of a remote machine, you can always SSH to it and find it out using the
uptime command. If you want to do that for a whole bunch of remote machines though, it is a bit tedious. Thankfully, there are two small utilities named rup and rsysinfo that make it easy to get such info about a bunch of remote computers easily.
$ sudo apt install rstatd
$ sudo apt install rstat-client
$ rup foobar.mynet.com zumba.mynet.com yoga.mynet.com
$ rsysinfo foobar.mynet.com zumba.mynet.com yoga.mynet.com
Tried with: rstat 4.0.1 and Ubuntu 16.04