Experimental Physics and
Industrial Control System

"Williams Jr., Ernest L. via Core-talk" <core-talk at aps.anl.gov> · Wed, 16 Nov 2022 08:14:24 +0000

This issue is only happening with epicsCoreJava package we were using

Jesse, please copy in the details here
Jesse is also in contact with Kunal and Kay

Sent from my iPhone

> On Nov 15, 2022, at 11:11, Michael Davidsaver <mdavidsaver at gmail.com> wrote:
> 
> I realize I forgot to CC the core-talk list.
> 
>> On 11/9/22 06:51, Michael Davidsaver wrote:
>>> On 11/8/22 22:37, Kim, Kukhee wrote:
>>> Hi  Michael,
>>> 
>>> Thank you so much for your advice.
>>> The multicast address is:  224.0.0.128
>> Ah, right...  This address is used by PVA instead of something like caRepeater.
>> It should only be sent via the loopback interface through.
>> You can run "ip maddr" to see that 224.0.0.128 appears for the "lo" interface,
>> but not for any others.
>>> $ ip maddr
>>> 1:      lo
>>>         inet  224.0.0.128 users 2
>>>         inet  224.0.0.1
>>>         inet6 ff02::1
>>>         inet6 ff01::1
>> ...
>> Are you seeing packets with this destination address actually going out on a wire?
>>> We have PVA address setup as the followings:
>>> 
>>> EPICS_PVA_ADDR_LIST='<broadcast addr for subnet>  255.255.255.255'
>>> EPICS_PVA_AUTO_ADDR_LIST=NO
>>> EPICS_PVA_BROADCAST_PORT=5076
>>> EPICS_PVA_SERVER_PORT=507
>>> 
>>> Hi Ernest and Mike,
>>> 
>>> Can we capture the packet which goes to the multicast address to recognize searching or beacon?
>>> 
>>> Thank you for your help.  I will update you.
>>> 
>>> Thank you.
>>> Best regards,
>>> Kukhee
>>> 
>>> 
>>> 
>>> ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>>> *From:* Michael Davidsaver <mdavidsaver at gmail.com>
>>> *Sent:* Tuesday, November 8, 2022 9:14 PM
>>> *To:* Kim, Kukhee <khkim at slac.stanford.edu>
>>> *Cc:* Zelazny, Michael Stanley <zelazny at slac.stanford.edu>; core-talk at aps.anl.gov <core-talk at aps.anl.gov>
>>> *Subject:* Re: Question PVA environment variable
>>> On 11/8/22 13:00, Kim, Kukhee via Core-talk wrote:
>>>> Hi Everyone,
>>>> 
>>>> We just realized that some of our servers send out packets to port 5076 in multicasting address.
>>> 
>>> What multicast address(es) are you seeing?
>>> 
>>> Can you look (with packet capture) to see if these are
>>> search or beacon messages?
>>> 
>>> 
>>>> Since, the multicasting address is used for some of specific services, we would like to prevent the PVA, PVXS traffic to the multicasting address.
>>> 
>>> PVXS should not send any multicast traffic by default.
>>> (we have no assigned addresses to use for PVA)
>>> 
>>> 
>>>> Is there any PVA environment variables to control it?
>>> 
>>> https://mdavidsaver.github.io/pvxs/netconfig.html <https://mdavidsaver.github.io/pvxs/netconfig.html>
>>> 
>>> There are a couple, all of the form EPICS_PVA*_ADDR_LIST
>>> 
>>> 
>>>> Thank you so much for your help and support!
>>>> 
>>>> Best regards,
>>>> Kukhee
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> Kukhee Kim | *Engineering Physicist *
>>>> 
>>>> Advanced Controls Department
>>>> 
>>>> SLAC National Accelerator Laboratory | Menlo Park, CA
>>>> 
>>>> p: 650.926.4912 | m: 669.300.8192 | email: khkim at slac.stanford.edu
>>>> 
>>> 
>

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System