To install Shrew Soft IPsec VPN Client on CentOS 7, follow these steps.
yum groupinstall -y "Development Tools"
yum install -y wget qt qt-devel cmake make openssl-devel libedit-devel
wget -P /usr/src https://www.shrew.net/download/ike/ike-2.2.1-release.tgz
cd /usr/src
tar xf ike-2.2.1-release.tgz
cd ike
cmake -DCMAKE_INSTALL_PREFIX=/usr -DQTGUI=YES -DETCDIR=/etc -DNATT=YES
make
make install