[Nut-upsuser] tcp-wrapper not found

[Andrew Min Chang]

Hi, Charles!


Still, I am a little confused. Do you mean:

If I want to make a machine A with a USB UPS physicaly plugged into share its UPS to other machines (for example, B) in the local network, I should run processes like this:
1. A runs driver, and then runs upsd with a config of "LISTEN 127.0.0.1"
2. B runs NO driver, but upsd with a config of "LISTEN <IP of A>"

Meanwhile you mentioned that upsd is the network server. Do you mean that upsd on A servers the other upsd on B?

--
Andrew Chang
2012-03-17


I meaned to try various configurations to examine my theory, but I still stucked in "tcp-wrapper not found". Cross compiling makes things totally different.

PS: Is it better to send this question to nut-packager but nut-upsuser?


At 2012-03-16 20:31:58,"Charles Lepple" <clepple at gmail.com> wrote:
>On Mar 15, 2012, at 11:15 PM, Andrew Min Chang wrote:
>
>> 1. upsd is a server, this "server" serves "client" but the common meaning of "net server". Which means upsd could not be seen by other device within the same LAN.
>
>No, see below.
>
>> 2. The real "net server" of UPS are drivers, such as usbhid-ups. The permission of access from network are done by tcp-wrapper.
>
>Permissions can be controlled by tcp_wrappers, but the actual network server is upsd. (Drivers communicate with upsd over a Unix-domain socket, which is local to the master system.)
>
>> 3. If a slave device B wants to connect to a master device A with UPS plugged into, it just needs to run upsd with a "LISTEN <IP of A>" in upsd.conf
>
>Correct. (This is why the LISTEN directive is in upsd.conf, not ups.conf.)
>
>Also, in most cases, tcp_wrappers can be replaced by kernel-level firewall rules.
>
>-- 
>Charles Lepple
>clepple at gmail
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.alioth.debian.org/pipermail/nut-upsuser/attachments/20120317/f2e37b02/attachment.html>