Having small servers at office requires try to avoid a small number of problems one of then are electrical supply falitures, a quick way to solve this is connecting a UPS to the server and forget about cross your fingers when a power outtage makes act of presence.

In my case i have to configure a couple of small servers one with an old Yukai UPS and other with a Salicru ups.

If you want to get an ups  linux communication working follow  this steps:

Enable epel

yum install https://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-5.noarch.rpm

Install packages

yum install nut.x86_64 vim

Configure NUT

First search if your ups is supported in nut database and ensure that you select the desired driver Linux UPS Hardware Compatibility list

if your ups doesn’t appears in this list youl use your favourite web searcher for someone who try to fix these problems in case of Salicru appears to work with blazer_usb driver

vim /etc/ups/ups.conf

at the end of the file append these lines for mustek Yukai series

[yukai]
driver = blazer_usb
port = auto
desc = "Yukai PowerMust 600 usb"

next step is verify if your selected configuration is valid just type in your terminal

  upsdrvctl start

and shoud get some output like these

Network UPS Tools - UPS driver controller 2.7.2
Network UPS Tools - Megatec/Q1 protocol USB driver 0.11 (2.7.2)
Supported UPS detected with megatec protocol
Vendor information unavailable
No values provided for battery high/low voltages in ups.conf

Using 'guestimation' (low: 10.400000, high: 13.000000)!
Battery runtime will not be calculated (runtimecal not set)

after this you should configure your permissions ACL, in my case I only want query SAI status from the server only

so edit file /etc/ups/upsd.conf using this command

vim /etc/ups/upsd.conf

and append these text

ACL all 0.0.0.0/0
ACL localhost 127.0.0.1/32
ACCEPT localhost
REJECT all

 

 

after this you should add a user to check UPS status edditing   /etc/ups/upsd.users file

vim  vim /etc/ups/upsd.users

and append this text

[local_mon]
password = secretpass
allowfrom = localhost
upsmon master

Next step is link your ups with created user

add a line in file

 vim /etc/ups/upsmon.conf

with these content

MONITOR </etc/ups/ups.conf UPS name>@localhost 1 </etc/ups/upsd.users selected username> </etc/ups/upsd.users selected password> master

in this case

MONITOR yukai@localhost 1 local_mon secretpass master

Enable services

systemctl enable nut-monitor.service

systemctl enable nut-server.service

and start these services

systemctl start nut-server.service

systemctl start nut-monitor.service

sometimes at execute after execute “upsdrvctl start” command  it hijacks usb communication, this can be solved restarting system.

to check if ups is working just launch

upsc “ups name” and you should get an output like these

upsc yukai

battery.charge: 100
battery.voltage: 13.20
battery.voltage.high: 13.00
battery.voltage.low: 10.40
battery.voltage.nominal: 12.0
device.type: ups
driver.name: blazer_usb
driver.parameter.pollinterval: 2
driver.parameter.port: auto
driver.version: 2.7.2
driver.version.internal: 0.11
input.current.nominal: 1.0
input.frequency: 49.9
input.frequency.nominal: 50
input.voltage: 231.5
input.voltage.fault: 231.5
input.voltage.nominal: 230
output.voltage: 231.5
ups.beeper.status: enabled
ups.delay.shutdown: 30
ups.delay.start: 180
ups.load: 27
ups.productid: 5161
ups.status: OL
ups.type: offline / line interactive

references:

http://blog.shadypixel.com/monitoring-a-ups-with-nut-on-debian-or-ubuntu-linux/