Hello Andreas,
Thanks for your detailed answer!
Here is what I see in the $INFORMIXDIR/lib dir (no symblink):
informix@toro:/opt3/dbs/ifx/IDS-15.0.0.0/lib$ ls -l libisi*
-rwxr-xr-x 1 informix informix 142104 Dec 10 12:22 libisi_gsk.so.3.0
From a developer perspective, I do not need encryption features.
I could start the server and run our QA tests without problems after doing some adjustments for the BIGINT negative rowids, and the new syscolumns.collength size for TEXT/BYTE columns.
I did also run 50 times all our tests with the same fglrun process under valgrind --tool=massif and saw no memory leak (flat graph below):

BR,
Seb
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Sebastien FLAESCH
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Original Message:
Sent: Wed December 11, 2024 12:07 PM
From: Andreas Legner
Subject: V15 installer could not determine supported encryption library
I tried the same, on (Windows/WSL based) Debian 12, with same OpenSSL version, yet as a standard root-install:
- it didn't ask which encryption lib to use - because of the root-install??
- it successfully installed IBM GSKit
- it failed with same error
- in $INFORMIXDIR/lib/, the only libisi* item I got is libisi_gsk.so.3.0
- so no libisi_o*.3.0 which would be the OpenSSL variants (for OpenSSL versions)
- and no libisi.so.3 (sym link I'd assume) which probably is what "isisofile is null" is referring to
libisi (Informix Security Interface) is a wrapper layer around either GSKit or OpenSSL, for providing a unified internal interface to all those security and cryptographic calls.
It (libisi.so.3) would be a link to (or a copy of) one of the sub-system specific libisi_* objects, thus determining which system's gonna be used - basically the decision you made there for OpenSSL.
The error we're both seeing, you for OpenSSL and I for the (default?) GSKit, simply indicates the installer wasn't able to determine which shared object to create this link for...
libisi.so.3 now missing, as you correctly suspected, will disallow any security and encryption related functionality - and not be a problem as long as you'd not go there.
Only, it's not only TLS/SSL, or maybe column level encryption or Ear; what this also would disable is any edition other than the (default) Developer Edition.
The good news: you can very easily cure this problem by manually creating that sym link
Nonetheless, we'd like to understand this failure -> investigating...
And no, I'd not know that/where it remembers that GSKit/OpenSSL decision for a later ids_install.
BR,
Andreas
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Andreas Legner
Dev Engineer
HCL Software
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