Ruptime
This gives you the uptime and system load of shell servers.
centos7 up 45+18:04, 1 user, load 0.00, 0.01, 0.00 debian up 29+13:20, 4 users, load 2.07, 2.16, 2.18 fedora up 45+22:35, 0 users, load 0.14, 0.15, 0.13 ftp up 16:49, 0 users, load 9.39, 3.31, 1.87 mint up 40+05:22, 0 users, load 0.09, 0.07, 0.07 mxlinux up 45+22:33, 0 users, load 0.09, 0.07, 0.06 radius up 45+22:33, 1 user, load 0.15, 0.09, 0.09 scientific7 up 42+17:37, 1 user, load 1.82, 2.21, 2.29 ubuntu up 16+04:25, 5 users, load 0.18, 0.22, 0.23 zorin up 45+17:27, 6 users, load 0.17, 0.13, 0.10