My UPS, an APC BackUPS 650, seems ineffective under Linux. Originally I thought this was because it could not cope with the load, but it works OK under MS-Windows.
That is, when I pull the cord from the wall under Windows I get an alert the UPS is on battery. When I do the same under Linux, the system powers off immediately (not a controlled shutdown). I use the apcupsd on a woody system with 2.4.19 kernel. Suspecting a configuration problem, I reviewed my settings with APC tech support, but this didn't help. I also tried disabling the demon before pulling the plug; this didn't help. I think this kills the theory that it is a problem with apcupsd. I do notice that I get the error message LSR safety check engaged on ttyS1 whenever I run the apcupsd demon (as well as on system start up). I see in the newsgroups this is a sign that something is wrong with the serial driver, but I'm not sure what. ttyS1 is where the UPS communicates. Hmm, I suppose a further test would be to disconnect the serial cable and see if this makes a difference. Anyway, I'm at a bit of a loss to track this problem down, and would appreciate any assistance. Some theories, none compelling, that occur to me: 1) Something else is watching ttyS1 and causing the shutdown. (What?) 2) The UPS detects that communication has failed and shuts down. The problem with this theory is that the UPS uses simple (dumb) signalling: messages only go from the UPS to the computer. So there doesn't seem to be anyway the UPS would even know there was a problem. 3) The system draws more power under Linux than Windows 2000, and this is just enough to put the battery over the edge. This assumes something else is weakening the battery, because it nominally clearly has enough juice. However, my utility power is pretty poor, and this could strain the system. 4) apcupsd is still hanging around despite /etc/init.d/apcupsd stop, and it's still the culprit. (I can try removing the package). Some possibly relevant log entries (gaps indicate omissions): Jan 22 14:25:48 wheat kernel: Serial driver version 5.05c (2001-07-08) with MANY_PORTS SHARE_IRQ SERIAL_PCI ISAPNP enabled Jan 22 14:25:48 wheat kernel: ttyS00 at 0x03f8 (irq = 4) is a 16550A Jan 22 14:25:48 wheat kernel: ttyS02 at 0x03e8 (irq = 4) is a 16550A Jan 22 14:25:48 wheat kernel: ttyS01 at port 0x02f8 (irq = 3) is a 16550A Jan 22 14:25:48 wheat kernel: eth0: Setting 100mbps full-duplex based on auto-negotiated partner ability 41e1. Jan 22 14:25:48 wheat kernel: ttyS1: LSR safety check engaged! Jan 22 14:25:48 wheat last message repeated 2 times Jan 22 14:25:49 wheat kernel: ttyS1: LSR safety check engaged! Jan 22 14:25:49 wheat apcupsd[396]: apcupsd 3.8.5 (4 January 2002) debian startup succeeded There are no log entries from the time of the crash. genpower was on my system, but I removed it. acpid is installed -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
