[Oracle-l] Windows refusing connections

On Tue, Jan 12, 2010 at 1:25 PM, Jason Heinrich wrote:

This is a bit obscure and I can't reproduce it at will, but I was wondering
if anyone here has seen something similar. First the stats:
Oracle EE 10.2.0.4 Patch 26 (Oct09 CPU)
Windows Server 2003 SP2, x64, patched to the mega-update MS released about
the same time as the Oct09 CPU.

On this particular server, after applying both the patches mentioned above
at the end of October, my monitoring started reporting sporadic "ORA-12541:
TNS:no listener" errors. I've also seen the same error occasionally when I
do a lsnrctl status, but other clients don't seem to be affected. Also, the
same patches were applied to other servers, and they don't have the same
problem. Tracing revealed that something is blocking the connection.

I've tried a few things to resolve this, but nothing has worked so far:
- Added (QUEUESIZE=200) to the listener.ora
- Added a second port to the listener for the monitoring.
- Tried to balance incoming connections between the two ports. I still see
the error on both ports.

Oracle Support says the following: "From the error we see in the lsnrctl
trace, we see that something is blocking the connection to port 1521, on TCP
layer, not SqlNet. So, it must be something on the machine at physical layer
that rejects this connection to port 1521 or 1526." The fact that this
started after the Windows security patches were applied makes me suspicious
of that, but I'm uncertain which patch would be the culprit or how to prove
it, especially since other servers seem to be fine. Anybody else experience
this?

--
Jason Heinrich

On Tue, Jan 12, 2010 at 12:32 PM, Thomas Roach wrote:

Did you look at the Windows firewall settings? You may need to go into that
(in control panel) and allow ports 1521 and 1526. Also check for other
"soft" firewalls on the box. To test connectivity, see if you can telnet to
those ports from a remote box and then locally.

On Tue, Jan 12, 2010 at 10:48 AM, Jason Heinrich wrote:

(Including list)

I'm waiting for a definitive answer from the sysadmins to be sure, but it
doesn't look like there's a software filewall running on this server. Also,
connections *usually* work: in fact, I've not seen any errors on connections
from outside the box (the monitoring script is running on the same server).