# pssh -h ip.txt -i uptime
[1] 11:15:03 [SUCCESS] Mar.mars.he
11:15:11 up 4 days, 16:25, 1 user, load average: 0.00, 0.00, 0.00
[2] 11:15:03 [SUCCESS] Jan.mars.he
11:15:12 up 3 days, 23:26, 0 users, load average: 0.00, 0.00, 0.00
[3] 11:15:03 [SUCCESS] Feb.mars.he
11:15:12 up 4 days, 16:26, 2 users, load average: 0.08, 0.02, 0.01