What does "down" mean for your accounting server, Hans-Ulrich? If it means "logged off", this would explain the difference. For IAMUP, "down" means "unable to execute commands", which includes logged off but also stuck in a disabled loop and similar things. About twice a month we have to stop and restart the CEARN LISTSERV manually after it goes into such a loop (fixed in 1.6a). This accounts for the 9h we got this month. I don't know about other sites, though. Eric