Follow this guide here. On my system it looked like this as shown below.
First download the SCST 3.1.x branch as shown below. Note that we need the 3.1.x version which can be used with non-custom kernels for kernels > 2.6.30 which means that we don't need a custom kernel build anymore since this UEK kernel is a 3.x linux kernel.
[root@oracle67 scst]# wget https://sourceforge.net/projects/scst/files/scst/scst-3.1.0.tar.bz2/download
Then bunzip2 and untar it then cd to scst-3.1.0/scst directory.
[root@oracle67 scst]# make 2release
cd src && make 2release
make[1]: Entering directory `/root/scst-3.1.0/scst/src'
sed -i.aa s/"^E\?XTRA_CFLAGS += \-DCONFIG_SCST_EXTRACHECKS"/"#EXTRA_CFLAGS += \-DCONFIG_SCST_EXTRACHECKS"/ Makefile
grep "^#EXTRA_CFLAGS += \-DCONFIG_SCST_EXTRACHECKS" Makefile >/dev/null
sed -i.aa s/"^#\?EXTRA_CFLAGS += \-DCONFIG_SCST_TRACING"/"EXTRA_CFLAGS += \-DCONFIG_SCST_TRACING"/ Makefile
grep "^EXTRA_CFLAGS += \-DCONFIG_SCST_TRACING" Makefile >/dev/null
sed -i.aa s/"^E\?XTRA_CFLAGS += \-DCONFIG_SCST_DEBUG -g -fno-inline -fno-inline-functions"/"#EXTRA_CFLAGS += \-DCONFIG_SCST_DEBUG -g -fno-inline -fno-inline-functions"/ Makefile
grep "^#EXTRA_CFLAGS += \-DCONFIG_SCST_DEBUG -g -fno-inline -fno-inline-functions" Makefile >/dev/null
rm Makefile.aa
cd dev_handlers && make 2release
make[2]: Entering directory `/root/scst-3.1.0/scst/src/dev_handlers'
sed -i.aa s/"^E\?XTRA_CFLAGS += \-DCONFIG_SCST_EXTRACHECKS"/"#EXTRA_CFLAGS += \-DCONFIG_SCST_EXTRACHECKS"/ Makefile
grep "^#EXTRA_CFLAGS += \-DCONFIG_SCST_EXTRACHECKS" Makefile >/dev/null
sed -i.aa s/"^#\?EXTRA_CFLAGS += \-DCONFIG_SCST_TRACING"/"EXTRA_CFLAGS += \-DCONFIG_SCST_TRACING"/ Makefile
grep "^EXTRA_CFLAGS += \-DCONFIG_SCST_TRACING" Makefile >/dev/null
sed -i.aa s/"^E\?XTRA_CFLAGS += \-DCONFIG_SCST_DEBUG -g -fno-inline -fno-inline-functions"/"#EXTRA_CFLAGS += \-DCONFIG_SCST_DEBUG -g -fno-inline -fno-inline-functions"/ Makefile
grep "^#EXTRA_CFLAGS += \-DCONFIG_SCST_DEBUG -g -fno-inline -fno-inline-functions" Makefile >/dev/null
rm Makefile.aa
make[2]: Leaving directory `/root/scst-3.1.0/scst/src/dev_handlers'
make[1]: Leaving directory `/root/scst-3.1.0/scst/src'
[root@oracle67 scst]#
[root@oracle67 scst]# BUILD_2X_MODULE=y make all install
cd src && make all
make[1]: Entering directory `/root/scst-3.1.0/scst/src'
make -C /lib/modules/3.8.13-68.3.4.el6uek.x86_64/build SUBDIRS=/root/scst-3.1.0/scst/src BUILD_DEV=m
make[2]: Entering directory `/usr/src/kernels/3.8.13-68.3.4.el6uek.x86_64'
Building modules, stage 2.
MODPOST 10 modules
make[2]: Leaving directory `/usr/src/kernels/3.8.13-68.3.4.el6uek.x86_64'
make[1]: Leaving directory `/root/scst-3.1.0/scst/src'
cd src && make install
make[1]: Entering directory `/root/scst-3.1.0/scst/src'
make -C /lib/modules/3.8.13-68.3.4.el6uek.x86_64/build SUBDIRS=/root/scst-3.1.0/scst/src BUILD_DEV=m
make[2]: Entering directory `/usr/src/kernels/3.8.13-68.3.4.el6uek.x86_64'
Building modules, stage 2.
MODPOST 10 modules
make[2]: Leaving directory `/usr/src/kernels/3.8.13-68.3.4.el6uek.x86_64'
rm -f /lib/modules/3.8.13-68.3.4.el6uek.x86_64/extra/scsi_tgt.ko
install -d /lib/modules/3.8.13-68.3.4.el6uek.x86_64/extra
install -d /lib/modules/3.8.13-68.3.4.el6uek.x86_64/extra/dev_handlers
install -m 644 dev_handlers/*.ko /lib/modules/3.8.13-68.3.4.el6uek.x86_64/extra/dev_handlers
install -m 644 scst.ko /lib/modules/3.8.13-68.3.4.el6uek.x86_64/extra
install -d /usr/local/include/scst
header_files="backport.h scst.h scst_const.h scst_debug.h \
scst_itf_ver.h scst_sgv.h scst_user.h"; \
for h in ${header_files}; do \
install -m 644 ../include/$h /usr/local/include/scst; \
done
rm -f /usr/local/include/scst/Module.symvers
install -m 644 Module.symvers /usr/local/include/scst
/sbin/depmod -b / -a 3.8.13-68.3.4.el6uek.x86_64
mkdir -p /var/lib/scst/pr
mkdir -p /var/lib/scst/dif_tags
mkdir -p /var/lib/scst/vdev_mode_pages
****************************************************************
*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*
*!! !!*
*!! Now don't forget to rebuild and reinstall all your !!*
*!! target drivers, custom dev handlers and necessary user !!*
*!! space applications. Otherwise, because of the versions !!*
*!! mismatch, you could have many problems and crashes. !!*
*!! See IMPORTANT note in the "Installation" section of !!*
*!! SCST's README file for more info. !!*
*!! !!*
*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!*
****************************************************************
make[1]: Leaving directory `/root/scst-3.1.0/scst/src'
[root@oracle67 scst]# ls -l /lib/modules/`uname -r`/extra/scst*.ko
-rw-r--r--. 1 root root 6772424 Aug 3 20:37 /lib/modules/3.8.13-68.3.4.el6uek.x86_64/extra/scst.ko
[root@oracle67 scst]# for j in scst scst_vdisk scst_user ; do modprobe $j ; done
[root@oracle67 scst]#
[root@oracle67 scst]# lsmod | grep scst
scst_user 37776 0
scst_vdisk 99203 0
scst 1788033 2 scst_user,scst_vdisk
dlm 170381 1 scst
libcrc32c 1252 2 scst_vdisk,sctp
crc_t10dif 1547 2 scst,sd_mod
[root@oracle67 scst]#
Make sure you have iscsi-initiator-utils if you are going to have SCST target and client on the same host.
[root@oracle67 scst]# yum install -y iscsi-initiator-utils
Loaded plugins: refresh-packagekit, security
Setting up Install Process
Package iscsi-initiator-utils-6.2.0.873-21.0.1.el6.x86_64 already installed and latest version
Nothing to do
[root@oracle67 scst]#