I downloaded Informix 12.10.FC2 on my Linux SLES 11 SP3 using part number CIM0GEN.

After unzipping of the Informix media in /tmp/informix, I see the following files.

-rw-r--r--  1 root bin     10201 Aug 30 00:53 bundle.properties
drwxr-xr-x  3 root bin      4096 Aug 30 00:51 CSDK
drwxr-xr-x 11 root bin      4096 Aug 30 00:53 IBM_Data_Server_Driver_Package
drwxr-xr-x  3 root bin      4096 Aug 30 00:51 ICONNECT
-rwxr-xr-x  1 root bin 395384851 Aug 30 00:53 ids_install
drwxr-xr-x  5 root bin      4096 Aug 30 00:53 JDBC
-r--r--r--  1 root bin     12234 Aug 30 00:53 README.html
drwxr-xr-x  3 root bin      4096 Aug 30 00:53 SERVER

Before Install:

# groupadd -g 1010 informix
# useradd -u 1010 -g informix -d /home/informix -m informix
# passwd informix

Create /etc/bash.bashrc.local with the following entries:

export INFORMIXDIR=/opt/ibm/informix
export INFORMIXSERVER=informix
export ONCONFIG=onconfig.informix
export INFORMIXSQLHOSTS=/opt/ibm/informix/etc/sqlhosts.informix
export GL_USEGLU=1
export PATH=${INFORMIXDIR}/bin:${INFORMIXDIR}/extend/krakatoa/jre/bin:${PATH}
export DBEDIT=vi
export EDITOR=vi

Install Informix

# ./ids_install -i gui

I used custom install and selected the following.
Informix Directory: /opt/ibm/informix
Informix Instance Name: Informix
Port number: 55000

Start Informix for the First Time

Login as informix user and run the command.

$ oninit -ivwy
informix@iwrnode02:~> oninit -ivwy
Warning: Parameter's user-configured value was adjusted. (SHMVIRTSIZE)
Warning: Parameter's user-configured value was adjusted. (DS_MAX_SCANS)
Warning: Parameter's user-configured value was adjusted. (ONLIDX_MAXMEM)
Reading configuration file '/opt/ibm/informix/etc/onconfig.informix'...succeeded
Creating /INFORMIXTMP/.infxdirs...succeeded
Allocating and attaching to shared memory...succeeded
Creating resident pool 8306 kbytes...succeeded
Creating infos file "/opt/ibm/informix/etc/.infos.informix"...succeeded
Linking conf file "/opt/ibm/informix/etc/.conf.informix"...succeeded
Initializing rhead structure...rhlock_t 16384 (512K)... rlock_t (5312K)... Writing to infos file...succeeded
Initialization of Encryption...succeeded
Initializing ASF...succeeded
Initializing Dictionary Cache and SPL Routine Cache...succeeded
Bringing up ADM VP...succeeded
Creating VP classes...succeeded
Forking main_loop thread...succeeded
Initializing DR structures...succeeded
Forking 1 'soctcp' listener threads...succeeded
Forking 1 'soctcp' listener threads...succeeded
Forking 1 'soctcp' listener threads...succeeded

Stop Informix

Login as informix user and run the following command to stop the Informix server.

$ onmode -yuk

Start Informix After Initialization

iwrnode02:/opt/ibm/informix # oninit -vwy

Start Open Admin Tool

Login as root and change directory to $INFORMIXDIR/OAT and run the command.

iwrnode02:/opt/ibm/informix/OAT # ./StartApache 
/opt/ibm/informix/OAT/Apache_2.4.2/bin/httpd: error while loading shared libraries: 
libexpat.so.0: cannot open shared object file: No such file or directory

Fix this error by going to the /lib64 and create a symbolic link as shown:

# cd /lib64
# ln -s libexpat.so.1 libexpat.so.0

Run command again.

iwrnode02:/opt/ibm/informix/OAT # ./StartApache 
httpd: Syntax error on line 126 of /opt/ibm/informix/OAT/Apache_2.4.2/conf/httpd.conf: 
Cannot load /opt/ibm/informix/OAT/Apache_2.4.2/modules/mod_ssl.so into server: 
libssl.so.6: cannot open shared object file: No such file or directory

Fix this error by going to the /usr/lib64 and create a symbolic link as shown:

# cd /usr/lib64
# ln -s libssl.so.0.9.8 libssl.so.6

Run command again.

iwrnode02:/opt/ibm/informix/OAT # ./StartApache 
httpd: Syntax error on line 126 of /opt/ibm/informix/OAT/Apache_2.4.2/conf/httpd.conf: 
Cannot load /opt/ibm/informix/OAT/Apache_2.4.2/modules/mod_ssl.so into server: 
libcrypto.so.6: cannot open shared object file: No such file or directory

Fix this error by going to the /usr/lib64 and create a symbolic link as shown:

# cd /usr/lib64
# ln -s libcrypto.so.0.9.8 libcrypto.so.6

Run command again.

iwrnode02:/opt/ibm/informix/OAT # ./StartApache

Check if OAT started or not

iwrnode02:/opt/ibm/informix/OAT # netstat -aon | grep 8080
tcp        0      0 :::8080                 :::*                    LISTEN      off (0.00/0/0)
iwrnode02:/opt/ibm/informix/OAT # ps -ef | grep -i apache
root     14928     1  0 13:26 ?        00:00:00 /opt/ibm/informix/OAT/Apache_2.4.2/bin/httpd 
-f /opt/ibm/informix/OAT/Apache_2.4.2/conf/httpd.conf -k start
daemon   14929 14928  0 13:26 ?        00:00:00 /opt/ibm/informix/OAT/Apache_2.4.2/bin/httpd 
-f /opt/ibm/informix/OAT/Apache_2.4.2/conf/httpd.conf -k start
daemon   14930 14928  0 13:26 ?        00:00:00 /opt/ibm/informix/OAT/Apache_2.4.2/bin/httpd 
-f /opt/ibm/informix/OAT/Apache_2.4.2/conf/httpd.conf -k start
daemon   14936 14928  0 13:26 ?        00:00:00 /opt/ibm/informix/OAT/Apache_2.4.2/bin/httpd 
-f /opt/ibm/informix/OAT/Apache_2.4.2/conf/httpd.conf -k start

Configure OAT for the First Time