Informix News
18 Nov 13 - ZDNet - Top 20 mobile skills in demand... Read
09 Sep 13 - telecompaper - Shaspa and Tatung have shown a new smart home platform at Ifa in Berlin. Powered by the IBM Informix software... Read
06 Sep 13 - IBM data magazine - Mission Accomplished - Miami, Florida will be the backdrop for the 2014 IIUG Informix Conference... Read
01 Feb 13 - IBM Data Magazine - Are your database backups safe? Lester Knutsen (IBM Champion) writes about database back up safety using "archecker"... Read
14 Nov 12 - IBM - IBM's Big Data For Smart Grid Goes Live In Texas... Read
3 Oct 12 - The Financial - IBM and TransWorks Collaborate to Help Louisiana-Pacific Corporation Achieve Supply Chain Efficiency... Read
28 Aug 12 - techCLOUD9 - Splunk kicks up a SaaS Storm... Read
10 Aug 12 - businessCLOUD9 - Is this the other half of Cloud monitoring?... Read
3 Aug 12 - IBM data management - Supercharging the data warehouse while keeping costs down IBM Informix Warehouse Accelerator (IWA) delivers superior performance for in-memory analytics processing... Read
2 Aug 12 - channelbiz - Oninit Group launches Pay Per Pulse cloud-based service... Read
28 May 12 - Bloor - David Norfolk on the recent Informix benchmark "pretty impressive results"... Read
23 May 12 - DBTA - Informix Genero: A Way to Modernize Informix 4GL Applications... Read
9 Apr 12 - Mastering Data Management - Upping the Informix Ante: Advanced Data Tools... Read
22 Mar 12 - developerWorks - Optimizing Informix database access... Read
14 Mar 12 - - International Informix User Group set to meet in San Diego... Read
1 Mar 12 - IBM Data Management - IIUG Heads West for 2012 - Get ready for sun and sand in San Diego... Read
1 Mar 12 - IBM Data Management - Running Informix on Solid-State Drives.Speed Up Database Access... Read
26 Feb 12 - - Better results, lower cost for a broad set of new IBM clients and partners... Read
24 Feb 12 - developerWorks - Informix Warehouse Accelerator: Continuous Acceleration during Data Refresh... Read
6 Feb 12 - PRLOG - Informix port delivers unlimited database scalability for popular SaaS application ... Read
2 Feb 12 - developerWorks - Loading data with the IBM Informix TimeSeries Plug-in for Data Studio... Read
1 Feb 12 - developerWorks - 100 Tech Tips, #47: Log-in to Fix Central... Read
13 Jan 12 - MC Press online - Informix Dynamic Server Entices New Users with Free Production Edition ... Read
11 Jan 12 - Computerworld - Ecologic Analytics and Landis+Gyr -- Suitors Decide to Tie the Knot... Read
9 Jan 12 - - DNS impact on Informix / Impacto do DNS no Informix... Read
8 Sep 11 - - IBM Offers Database Solution to Enable Smart Meter Data Capture... Read
1 Aug 11 - IBM Data Management Magazine - IIUG user view: Happy 10th anniversary to IBM and Informix... Read
8 Jul 11 - Database Trends and Applications - Managing Time Series Data with Informix... Read
31 May 11 - Smart Grid - The meter data management pitfall utilities are overlooking... Read
27 May 11 - IBM Data Management Magazine - IIUG user view: Big data, big time ( Series data, warehouse acceleration, and 4GLs )... Read
16 May 11 - Business Wire - HiT Software Announces DBMoto for Enterprise Integration, Adds Informix. Log-based Change Data Capture... Read
21 Mar 11 - Yahoo! Finance - IBM and Cable&Wireless Worldwide Announce UK Smart Energy Cloud... Read
14 Mar 11 - MarketWatch - Fuzzy Logix and IBM Unveil In-Database Analytics for IBM Informix... Read
11 Mar 11 - InvestorPlace - It's Time to Give IBM Props: How many tech stocks are up 53% since the dot-com boom?... Read
9 Mar 11 - DBTA - Database Administration and the Goal of Diminishing Downtime... Read
2 Feb 11 - DBTAs - Informix 11.7 Flexible Grid Provides a Different Way of Looking at Database Servers... Read
27 Jan 11 - exactsolutions - Exact to Add Informix Support to Database Replay, SQL Monitoring Solutions... Read
25 Jan 11 - PR Newswire - Bank of China in the UK Works With IBM to Become a Smarter, Greener Bank... Read
12 Oct 10 - Database Trends and Applications - Informix 11.7: The Beginning of the Next Decade of IBM Informix... Read
20 Sep 10 - - ITG analyst paper: Cost/Benefit case for IBM Informix as compared to Microsoft SQL Server... Read
20 Jul 10 - IBM Announcements - IBM Informix Choice Edition V11.50 helps deploy low-cost scalable and reliable solutions for Apple Macintosh and Microsoft Windows... Read
20 Jul 10 - IBM Announcements - Software withdrawal: Elite Support for Informix Ultimate-C Edition... Read
24 May 10 - eWeek Europe - IBM Supplies Database Tech For EU Smart Grid... Read
23 May 10 - SiliconIndia - IBM's smart metering system allows wise use of energy... Read
21 May 10 - CNET - IBM to help people monitor energy use... Read
20 May 10 - ebiz - IBM Teams With Hildebrand To Bring Smart Metering To Homes Across Britain... Read
19 May 10 - The New Blog Times - Misurare il consumo energetico: DEHEMS è pronto... Read
19 May 10 - ZDNet - IBM software in your home? Pact enables five-city smart meter pilot in Europe... Read
17 March 10 - ZDNet (blog) David Morgenstern - TCO: New research finds Macs in the enterprise easier, cheaper to manage than... Read
17 March 2010 - Virtualization Review - ...key components of Big Blue's platform to the commercial cloud such as its WebSphere suite of application ser vers and its DB2 and Informix databases... Read
10 February 2010 - The Wall Street Journal - International Business Machines is expanding an initiative to win over students and professors on its products. How do they lure the college crowd?... Read

End of Support Dates

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5. Having Problems?

5.1 How do I allow remote connections?

Due to a bug #97893 (specific to Linux) and #97889 (for Solaris, considered closed) in sqlexecd, which listens for remote clients and fires off a sqlexec process for these connections, when the sqlexec session terminates, it leaves a zombie in your process table (see What are these zombies in my process table? and How do I prevent them?). This caveat aside, if you still insist, do the following:

  • Configure $INFORMIXDIR/etc/sqlhosts to use the sqlexecd daemon
      Change seipcpip to sesoctcp.
    1. Change sqlexec to sqlexecd.
  • Configure /etc/services on the server box. Add the line

    sqlexecd 1536/tcp

    The entry can be placed anywhere in the file. You can use any other port number instead of 1536 as long as it is not already in use.

  • Run sqlexecd to listen to that port and start a sqlexec session for remote clients

    $INFORMIXDIR/lib/sqlexecd demo_se This example assumes that your dbserver name is demo_se.

5.2 What are these zombies in my process table?

They are Informix's way of saying, "We take a licking and keep on ticking!" ;-) Seriously, they are the manifestation of Bug #97893. It seems to occur most often when using sockets (sesoctcp) to provide remote access to a database. There are also reports of it occurring when using unnamed pipes (seipcpip) on local connections.

In an interesting twist, Bug #97893 has been fixed in the glibc release, but a new bug, #101155 has been entered: the SEIPCPIP connection protocol (pipes) does not work on the RedHat 5.1 platform.

5.3 How do I prevent them?

Jonathan Leffler ( posted a work-around, nozombie.c, that is used in the the same manner as nohup. Jonathan's code and his remarks follow. Note that this is not an official (approved by Informix) fix, and there are also reports that it does not work in every case. YMMV.

The explanation is fairly simple -- if the process is ignoring the signal SIGCHLD, then it doesn't accumulate zombie children. The program sets the signal handling mode for SIGCHLD to SIG_IGN and then runs whatever it was given as arguments. If this happens to be sqlexecd, it seems to ignore the SIGCHLD signals, thereby leaving no zombies around.

@(#)Last changed:

$RCSfile: nozombie.c,v $
$Revision: 1.1 $
$Date: 1998/08/20 21:24:40 $
Prevent process from accidentally creating zombies
J Leffler
(C) JLSS 1998
/*TABSTOP=4*/ #include <signal.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

#ifndef lint
static const char rcs[] = "@(#)$Id: nozombie.c,v 1.1 1998/08/20 21:24:40 jleffler Exp $";
#endif /*
** Exec program specified by arguments with SIGCHLD signals ignored.
** This ensures that unless the program re-enables the SIGCHLD signal
** handling, it does not leave zombies around, even if it doesn't
** clean up behind its children. This works on POSIX.1 systems (such
** as Solaris 2.6 and Linux) pretty straight-forwardly.
** Motivation: the initial version of sqlexecd 7.24.UC1 on Linux
** caused problems with lots of zombies.
**   nozombie $INFORMIXDIR/lib/sqlexecd [service]

int main(int argc, char **argv)
    signal(SIGCHLD, SIG_IGN);
    execv(argv[1], &argv[1]);
    fprintf(stderr, "Failed to execv() %s\n", argv[1]);
    return EXIT_FAILURE; }

If Jonathan's code doesn't solve it, try the following, which appeared recently in informix.idn.linux. It fixes the zombie problem by rewriting the way the signal function works.

First, create a signalfix.c as follows:

#include "signal.h"
#include <unistd.h>
#include <stdio.h>

void *signal(int signum,void (*handler)(int))
   struct sigaction sa;
   sigaction(signum,&sa,(struct sigaction *)NULL);

Next, copy /usr/include/signal.h, and comment out the signal function. Then, compile signalfix.c thusly:

$ gcc -fpic -shared signalfix.c -o

Finally, run sqlexecd with:
$ LD_PRELOAD=/root/sqlexecfix/ $INFORMIXDIR/lib/sqlexecd servername

5.4 DBACCESS seg faults in my xterm!

The immediate problem is that dbaccess apparently allocates a static buffer to hold the termcap/terminfo entry and that your entry is longer than this buffer will hold. One day Real Soon Now (c), I'll report this to Informix, hopefully in time to get it fixed in the next release cycle.

In the meantime, work-arounds include:

  1. Changing the $TERM environment variable to something other than xterm, such as linux, vt220 or vt100
  2. Modifying the relevant entry in termcap or terminfo (after making a backup copy, of course). dbaccess does not use the "ti" or "te" entries, so they can be deleted. This works, but it will affect all xterm sessions, include those that might actually use the ti/te entries.
  3. Clone the xterm entry as, say, xterm-dbaccess, delete the "ti" and "te" entries, and set the $TERM environment variable to xterm-dbaccess when you want to run dbaccess in an xterm window.
  4. Use the replacement termcap/terminfo file available at Note the warnings and suggestions listed there.

Roger Allen ( recommends the third option, explaining Either make a copy of the xterm entry in /etc/termcap with a different name and use the new name as your TERM setting or change the current entry. Somewhere in an appendix of some of the Informix manuals is a list of the fields that Informix uses. I usually delete the ti and te fields. You also may be able to add the special Informix entries that will enable color, line drawing characters, and more function keys, but that is more for the Informix tools than DB-Access.

5.5 The port I'm supposed to use is already being used!

Use another one. The canonical Informix port is 1536, but it really doesn't care which socket it uses, so long as it is not in use by another service.

5.6 Can I use an NFS-mounted filesystem?

No. Rather than mounting the filesystem that holds your database via NFS,

  1. The remote host must be running sqlexecd, and
  2. You must access the remote database using the network

Non-Linux versions of SE enforce this in the binaries, but this may not be the case with the Linux product. As Jonathan Leffler advises, "expect problems if you try to cheat -- data corruption problems."

Whether this is enforced by the binaries or not, mounting your database on an NFS mount is a bad idea for (at least) two reasons:

  1. Access will be slow, because NFS is slow.
  2. If you lose your NFS mounts, you're screwed, and who knows what happens to your databases files.

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