You are installing a sap server with DB2 database on Unix/Linux System. During executing db2 binaries, for example db2start you get following error:
SQL1641N The db2start command failed because one or more DB2 database manager program files was prevented from executing with root privileges by file system mount settings.
Check if the file systems are not mounted with option nosuid.
Nosuid option prevents the programs to be executed by the users apart from the owner of binaries
Change the mount options (example for Linux fstab):
/dev/mapper/local_vg-lvx /db2/XXX/sapdata2 ext4 nodev,nosuid 1 2
/dev/mapper/local_vg-lvx /db2/XXX/sapdata2 ext4 defaults 1 2