Informix ODBC Error: Read error occured during con
A user running Informix 12.10 on RHEL 6 with ODBC clients on a Windows 2003/IIS6 web server saw intermittent "Read error occurred during connection attempt" failures, logged in online.log as error -27001 from the listener thread; the ODBC DSN test and PHP/Apache access on the Linux box worked fine. Respondents suggested checking connection rates and connection reuse, LISTEN_TIMEOUT and MAX_INCOMPLETE_CONNECTIONS, reverse DNS lookups on the server (forcing /etc/nsswitch.conf to "hosts: files" only), and the MSDTC XADLL registry entry for iclit09b.dll. The poster reported low load, correct settings and that the registry entry already existed. No resolution is recorded in the thread.
Auto-generated by DrWatson from the posts below — may be imperfect; read the full thread.
We have Informix 12.10 installed on RHEL 6. ODBC connection is configured on
Windows 2003 using IIS6. On our webpages we are getting "Read error occured
during connection attempt".
Everything works fine on the RHEL server where we have hosted a php
application on Apache.
During my research i found out that it is related to NETTYPE config in the
onconfig file, following is our configuration:
NETTYPE ipcshm,6,300,NET
NETTYPE soctcp,6,300,CPU
Any suggestions would be much appreciated.
Under the ODBC/DSN connection control panel option - is the test connection
working ?
Do you know the underpinning error number?
Cheers
Paul
> -----Original Message-----
> From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf Of
> SANJIV KUMAR
> Sent: Friday, October 04, 2013 11:22 AM
> To: ids@iiug.org
> Subject: Informix ODBC Error: Read error occured during con [31605]
>
> We have Informix 12.10 installed on RHEL 6. ODBC connection is configured
> on
> Windows 2003 using IIS6. On our webpages we are getting "Read error
> occured
> during connection attempt".
>
> Everything works fine on the RHEL server where we have hosted a php
> application on Apache.
>
> During my research i found out that it is related to NETTYPE config in the
> onconfig file, following is our configuration:
>
> NETTYPE ipcshm,6,300,NET
> NETTYPE soctcp,6,300,CPU>
> Any suggestions would be much appreciated.
>
>
> **********************************************************
> *********************
> Forum Note: Use "Reply" to post a response in the discussion forum.
Yes, test connection works. Even web pages works fine. Error shows up intermittently. Following is the log from online.log show error 27001 08:03:11 listener-thread: err = -27001: oserr = 0: errstr = from WIN2K3 to server RHEL6_tcp : Read error occurred during connection attempt.
What do you see on your server online.log?
This can be a complex issue... How many connections are you making per
second? Your web applications should re-use the connections. Can you
confirm that is happening?
If your're open too many connections per second you may be hitting some
configuration issues...
What is the setup for this values:
MAX_INCOMPLETE_CONNECTIONS
LISTEN_TIMEOUT
How are your database server resolving DNS requests? For every connection
attempt the server will try to reverse lookup the client (web server) ip
address. If there are problems here it may cause some of the issues you're
seeing.
Also... Any restrictions on the "client"? If the client is overloaded and
doing too many connections per second it may not finish the protocol
negotiations (depending on the parameters above) and it may also cause
this...
Regards
On Fri, Oct 4, 2013 at 5:22 PM, SANJIV KUMAR <sanjiv@simple2call.com> wrote:
> We have Informix 12.10 installed on RHEL 6. ODBC connection is configured
> on
> Windows 2003 using IIS6. On our webpages we are getting "Read error occured
> during connection attempt".
>
> Everything works fine on the RHEL server where we have hosted a php
> application on Apache.
>
> During my research i found out that it is related to NETTYPE config in the
> onconfig file, following is our configuration:
>
> NETTYPE ipcshm,6,300,NET
> NETTYPE soctcp,6,300,CPU>
> Any suggestions would be much appreciated.
>
>
>
>
*******************************************************************************
> Forum Note: Use "Reply" to post a response in the discussion forum.
>
>
--
Fernando Nunes
Portugal
http://informix-technology.blogspot.com
My email works... but I don't check it frequently...
--001a11c3409ccb867104e7ed0788
I'm so happy to see the message... "from .... to server ...."... A few months ago it didin't contain that info, which made it nasty to debug... It's a proof that opening PMRs pays off :) On Fri, Oct 4, 2013 at 5:33 PM, SANJIV KUMAR <sanjiv@simple2call.com> wrote: > Yes, test connection works. Even web pages works fine. Error shows up > intermittently. > > Following is the log from online.log show error 27001 > > 08:03:11 listener-thread: err = -27001: oserr = 0: errstr = from WIN2K3 to > server RHEL6_tcp : Read error occurred during connection attempt. > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > -- Fernando Nunes Portugal http://informix-technology.blogspot.com My email works... but I don't check it frequently... --001a113366bcbd613004e7ed0fe3
Try this
The problem isolation step may look like this.
Check whether ODBC standalone application (with the same ODBC driver) w=
orks
on the same system (The system where IIS is running).
If the above works then the problem is IIS setup on the system.
Based on the way the web business logic is deployed at application serv=
er
under IIS there could be some extra security setup needed.
If your business logic that use Informix ODBC driver gets executed unde=
r
DllHost (the application server) then you may need the following setup.=
http://support.microsoft.com/kb/817066
Though the documentation may be describing about XADLL, the IIS
architecture to invoke web business logic is somewhat same.
So I am expecting the same requirement here as well.
In short you may create a 'String Value' in the name of
'iclit09b.dll' (iclit09b.dll is the ODBC DRIVER DLL) under
windows registry 'HKEY_LOCAL_MACHINE\\\\SOFTWARE\\\\Microsoft\\\\MSDTC\\\\XADLL'
Then add value to the key by giving absolute path to 'iclit09b.dll'
For example :
C:\\\\informix\\\\bin\\\\iclit09b.dll
Regards,
Satyan
Advisory Software Engineer
R&D - IBM Information Management Division
11200 Lakeview, Lenexa, KS 66219
Tel: 913 599 8792 (T/L: 337-8792)
From: "SANJIV KUMAR" <sanjiv@simple2call.com>
To: ids@iiug.org,
Date: 10/04/2013 11:22 AM
Subject: Informix ODBC Error: Read error occured during con [31605]
Sent by: ids-bounces@iiug.org
We have Informix 12.10 installed on RHEL 6. ODBC connection is configur=
ed
on
Windows 2003 using IIS6. On our webpages we are getting "Read error occ=
ured
during connection attempt".
Everything works fine on the RHEL server where we have hosted a php
application on Apache.
During my research i found out that it is related to NETTYPE config in =
the
onconfig file, following is our configuration:
NETTYPE ipcshm,6,300,NET
NETTYPE soctcp,6,300,CPU
Any suggestions would be much appreciated.
***********************************************************************=
********
Forum Note: Use "Reply" to post a response in the discussion forum.
=
LISTEN_TIMEOUT 60
MAX_INCOMPLETE_CONNECTIONS 1024
Both RHEL and Windows server are at same geographical location connected to
the same ethernet switch using same IP subnet.
I have put the hostname and ip address in the windows server in host file of
RHEL server.
This registery entry is already there.
This server is probably running couple of thousand transactions a day. Not too busy.
On Fri, Oct 4, 2013 at 9:58 PM, SANJIV KUMAR <sanjiv@simple2call.com> wrote:
> LISTEN_TIMEOUT 60
> MAX_INCOMPLETE_CONNECTIONS 1024>
> It would take some lost connection attempt to make this a problem...
>
> Both RHEL and Windows server are at same geographical location connected to
> the same ethernet switch using same IP subnet.
>
> I have put the hostname and ip address in the windows server in host file
> of
> RHEL server.
>
> On Linux, it doesn't guarantee (by default, last time I checked) that it
will not try to talk with the DNS...
On /etc/nsswitch.conf you'll find an entry like:
hosts files dns
To be absolutely sure you would have to change this to:
hosts files
and restart Informix (one of my pet feature requests...)
But I doubt this is your problem... But if it's a non production system you
may want to try it.
But I'm wondering if you have any errors on the application layer? Or do
you only get the -27001 error in the onlinge.log of the database server? If
that's the case, have you installed any tool in windows to test for
connectivity to the database?
Regards
>
>
*******************************************************************************
> Forum Note: Use "Reply" to post a response in the discussion forum.
>
>
--
Fernando Nunes
Portugal
http://informix-technology.blogspot.com
My email works... but I don't check it frequently...
--001a11c264a47276ff04e7f2a114