Thank you, Tom! I think you may be onto something. The link you’ve provided 
seems rather informative. Some of it went over my head, but I’m sure some of my 
colleagues will be able to  comprehend it better than I did.

I just wanted to follow up with some more information and screenshot from 
avahi-discover (see attached), regarding what is happening.

-          We have several machines (in screenshot they are cpcssil1, sil1, and 
avlab2u).

-          Each machine can have many instances of a UI Server running.

-          UI Server publishes itself as a service on the network.

-          The service name is always unique in a format of 
UIS_<hostname>_<username>_<port>. I’m aware of a service name conflict 
resolution, and that is handled via adding ‘#2’ to the service name.
In the screenshot, you can see that there are 2 services running on cpcssil1 
and 2 services running on avlab2u. I didn’t capture it in a screenshot, but the 
Address for those is shown correctly in avahi-discover as “cpcssil1.local” and 
“avlab2u.local”.
When a user runs a Login Client (the client has the discovery), it will 
correctly pick up all the services, and if it will have no problem connecting 
to “avlab2u:30007”.
Also in the screenshot, you can see that the highlighted sil1 machine, has the 
address of “sil1-2.local” which is not correct. If you try to ping sil1-2, it 
does not exist. If you try to connect to sil1-2:30003, it does not exist.

Do you still suspect that the issue is due to the conflict resolution? Do you 
think adding a flag “AVAHI_PUBLISH_ALLOW_MULTIPLE - For raw records: Allow 
multiple local records of this type, even if they are intended to be unique.” 
Might solve the issue?

Thank you,
Denis

From: avahi [mailto:avahi-boun...@lists.freedesktop.org] On Behalf Of Tom 
Pusateri
Sent: Monday, June 19, 2017 7:27 PM
To: Avahi ML <avahi@lists.freedesktop.org>
Subject: Re: [avahi] Published service gets incorrect address

Without more information, this sounds like normal naming conflict resolution as 
described in:

https://tools.ietf.org/html/rfc6762#page-31

Another host on the link local network is using the same name and so your name 
is made unique by appending “-2”.

Sometimes, this occurs when a single host has multiple interfaces on the same 
link local network (like wired and wireless ethernet) or when there are bugs in 
the conflict resolution implementations.

This is harmless as long as your host is correctly resolving this name with the 
“-2” appended.

If you have mdns name resolution configured, you can ping (or ping6 if 
appropriate) "<name>-2.local” to see if it is resolving ok.

By killing the avahi-daemon, it is probably starting to use <name> again until 
conflict resolution kicked in and causes the name change to append the “-2”.

If this is not accurate, please send more detailed info (logs, packet traces, 
etc.).

Thanks,
Tom

On Jun 19, 2017, at 9:51 AM, Denis Kharlamov 
<dkharla...@aversan.com<mailto:dkharla...@aversan.com>> wrote:

Hello,

I’m experiencing a peculiar issue with my avahi where the address of the 
published service gets a “-2” appended to it.

My use of Avahi is essentially this: 
http://www.avahi.org/doxygen/html/client-publish-service_8c-example.html
The service always gets published without fail, with the correct service name, 
and TXT records. However, the address that avahi-discover shows, has a -2 
appended to it.
I am not sure why, because in code I am passing a null pointer for the host, as 
per documentation:
“The host this services is residing on. We recommend to pass NULL here, the 
daemon will than automatically insert the local host name in that case”

The only way I’ve been able to resolve this is by killing the avahi-daemon and 
restarting it. Does anyone have any idea as to what could be causing this 
behavior?

Thank you,
Denis Kharlamov

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