Ruptime
This gives you the uptime and system load of shell servers.
centos7 up 43+12:40, 3 users, load 0.27, 0.13, 0.09 debian up 27+07:56, 5 users, load 2.09, 2.17, 2.17 fedora up 43+17:08, 0 users, load 0.31, 0.20, 0.13 ftp up 20+08:40, 0 users, load 0.40, 0.50, 0.58 mint up 37+23:58, 0 users, load 0.09, 0.06, 0.05 mxlinux up 43+17:09, 0 users, load 0.09, 0.07, 0.08 radius up 43+17:09, 2 users, load 0.26, 0.14, 0.10 scientific7 up 40+12:13, 1 user, load 2.16, 2.38, 2.52 ubuntu up 13+23:01, 5 users, load 0.48, 0.32, 0.29 zorin up 43+12:03, 6 users, load 0.02, 0.04, 0.00