Finally, urbanstreams.net is on-line full-time after a long frustrating search for the cause of the server’s random rebooting problem. The multitude of websites out there that advise on random rebooting problems suggest numerous possibilities, but I didn’t find a pointer to what turned out to be my problem: a faulty power supply. I’ve bought a new one and it is now behaving itself (fingers crossed).
Now I just need to talk Optus into unblocking port 80 and the website will actually be findable. (Or I might have to wait until the server moves in a couple of months). Here’s to a happy 2014.