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<== Date ==> <== Thread ==>

Subject: RE: Beacon and caRepeater
From: Emmanuel Mayssat <[email protected]>
To: Jeff Hill <[email protected]>
Cc: [email protected]
Date: Tue, 02 Oct 2007 18:00:44 -0700
On Mon, 2007-10-01 at 15:47 -0600, Jeff Hill wrote:
> The rate at which name resolution (search) requests are sent exponentially
> backs off to a plateau rate. The value of this plateau has an impact on
> network traffic because it determines the rate that clients search for
> channel names that are miss-spelled or otherwise don't exist in a server.
> Furthermore, for clients that are unable to see the beacon from a new
> server, the plateau rate may also determine the maximum interval that the
> client will wait until discovering a new server.
> 
> Starting with EPICS R3.14.7 this maximum search rate interval plateau in
> seconds is determined by the EPICS_CA_MAX_SEARCH_PERIOD environment
> variable.

This obviously implies recompilation of the extensions (medm, etc)
against the new base, isn't it?
In my case, my medm doesn't work correctly with 3.14.6+
http://www.aps.anl.gov/epics/tech-talk/2007/msg00744.php
Could that be related to channel access?

I am now able to make sense of the details of the CA client - CA server
communication.

EPICS_CA_ADDR_LIST is a list of servers where to send search requests
EPICS_CAS_BEACON_ADDR_LIST is a list of repeaters where to send beacons
But then why do we have EPICS_CAS_BEACON_LIST default to the value of
EPICS_CA_ADDR_LIST if the former is not set? Can we send beacons and
search requests to the same port? That doesn't make any sense to me...

Regards,

--
Emmanuel



Replies:
RE: Beacon and caRepeater Jeff Hill
References:
Beacon and caRepeater Emmanuel Mayssat
RE: Beacon and caRepeater Jeff Hill

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