There was a download of SentryII 1.3 on the developer's website when we last checked. We cannot confirm if there is a free download of this software available. SentryII is included in Internet & Network Tools.
The following versions: 1.3 and 1.0 are the most frequently downloaded ones by the program users. This free program was originally produced by Minuteman. ConnectToServer.exe is the most common filename for this program's installer. We recommend checking the downloaded files with any free antivirus.
From the developer:
Sentry II is a UPS power monitoring application for the Windows 95/98/ME, Windows NT/2000/XP, SCO Unixware/Open Desktop, HP-UX, IBM AIX, Red Hat Linux, Tru-64 UNIX, and Novell Netware 4.x, 5.x operating systems. Sentry II monitors the UPS through a cable attached to a serial port on the computer, and the communications interface on the UPS.
You may want to check out more software, such as Plesk for Windows, FRITZ! or Prestwood Ping Server, which might be similar to SentryII.