Hi catch_mili
it is not mandatory to install it in /opt, you can install it on any support file system. You tried to install splunk> in the memory = /tmp which is not support as the error message states.
you can find here a table of all supported file systems or take a look at this table:
Platform File systems
Linux ext2/3/4, reiser3, XFS, NFS 3/4
Solaris UFS, ZFS, VXFS, NFS 3/4
FreeBSD FFS, UFS, NFS 3/4, ZFS
Mac OS X HFS, NFS 3/4
AIX JFS, JFS2, NFS 3/4
HP-UX VXFS, NFS 3/4
Windows NTFS, FAT32
cherrs,
MuS
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