We are running several demo registration servers whose 'control panels' are shown below.
Normally a server log would close, cross-register and the next start (roll) every hour, every day or after so many registrations. Here, each log rolls when commanded explicily. Use the browser 'back' command to return to the control panels after the results.
Green Server: submits checksums to itself, yellow and blue
Yellow Server: submits checksums to itself and green
Blue Server: submits checksums to itself and yellow
Purple Server: submits checksums to itself and yellow and green