[Nut-upsdev] no serial number for Tripp-Lite SMART3000RM2U?

[Charles Lepple]

On Jun 7, 2012, at 12:59 PM, Seth Galitzer wrote:

> upsrw reports ups.id is a string, which could be useful if I could match against it, but if I read your statement correctly, I cannot.

Correct. All of the strings returned by upsrw and upsc are populated after the matching occurs, but some of them happen to be available earlier (the ones which are visible with lsusb)

> Matching on USB bus number would not be optimal, since this changes even when a device is unplugged and replugged along with in between system boots.  So I'd have to look them all up and reconfigure ups.conf with every reboot.  Doable, but a royal pain to maintain.

Agreed. In situations like this, I have split the racks up so that each UPS is monitored by a server in its own rack, with no more than one USB connection per server. Or if one server has to monitor two UPSes, we would put two different models together (e.g. a 1500 VA with a 3000 VA).

> I didn't realize nut was using some kernel drivers.  I just assumed everything was all local to the app.

The driver that NUT uses is essentially a passthrough interface for libusb (usbdevfs, or something), but in some cases, there is a USB HID driver that NUT needs to detach before it can use usbdevfs. Neither of these drivers offers a persistent numbering scheme if there is no USB serial number, however.

-- 
Charles Lepple
clepple at gmail