Experimental Physics and
Industrial Control System

Matthieu Bec <[email protected]> · Thu, 4 Nov 2010 12:48:41 -0300

Hi Mark,
I left it as an unanswered question but came to the conclusion the udp
destination needed to be widely open:
# anything on VLAN65:

-A INPUT -m state --state NEW -m udp -p udp -s 172.16.65.0/24 --dport
5000:65535 -j ACCEPT
get 'wireshark' if you cannot find ethereal for your distribution.
Matthieu

On 11/04/10 12:24, Mark Rivers wrote:

Hi Eric,
I suspect the problem is that the broadcast messages from the client are not making it through the firewall. I had a similar problem with a Windows firewall.
You can run ethereal on another machine and see if it is seeing the client broadcasts.
Mark

________________________________
From: [email protected] on behalf of Eric Norum
Sent: Thu 11/4/2010 10:22 AM
To: EPICS Techtalk
Subject: Firewall (iptables) issues?

Apologies if this is a FAQ. I'm new to the intricacies of Linux firewalls.
I'm trying to get a linux system
Linux xildev2 2.6.18-194.11.3.el5.lbl1 #1 SMP Thu Sep 16 14:50:58 PDT 2010 x86_64 x86_64 x86_64 GNU/Linux
to work as a channel access client.
If I use EPICS_CA_ADDR_LIST to explicitly provide the address of my IOC things work fine. If I leave EPICS_CA_ADDR_LIST undefined my client applications see no PVs.
I poked holes in the firewall for the channel-access ports:
iptables -L
.
.
ACCEPT     udp  --  anywhere             anywhere            udp dpt:ca-1
ACCEPT     udp  --  anywhere             anywhere            udp dpt:ca-2
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:ca-1
ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:ca-2
.
.
but that didn't seem to make any difference.
I restarted caRepeater after making the firewall changes.  Still no PVs.
Suggestions?
--
Eric Norum
[email protected]

--
Matthieu Bec              Gemini Observatory
Tel: +56 51 205785        c/o AURA, Casilla 603
Fax: +56 51 205650        La Serena, Chile

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System