title: Rhel + Kernel header files not in any of the expected locations - when installing network driver
body: <p>we try to installe the network driver - <code>i40e</code> on rhel server 7.2 version , ( kernel - 3.10.0-512 )</p>
  <p>as the following</p>
  <pre><code># tar zxf i40e-2.12.6.tar.gz
  # cd i40e-2.12.6/src
  # make install
  common.mk:82: *** Kernel header files not in any of the expected locations.
  common.mk:83: *** Install the appropriate kernel development package, e.g.
  common.mk:84: *** kernel-devel, for building kernel modules and try again.  Stop.
  </code></pre>
  <p>on other server ( rhel 7.2 ) its installed successfully as the following ( this is the second <code>make install</code> , so the output is little different from the first time )</p>
  <pre><code># cd src/
  # make install
  *** The target kernel has CONFIG_MODULE_SIG_ALL enabled, but
  *** the signing key cannot be found. Module signing has been
  *** disabled for this build.
  make[1]: Entering directory `/usr/src/kernels/3.10.0-327.el7.x86_64'
    Building modules, stage 2.
    MODPOST 1 modules
  make[1]: Leaving directory `/usr/src/kernels/3.10.0-327.el7.x86_64'
  Installing modules...
  *** The target kernel has CONFIG_MODULE_SIG_ALL enabled, but
  *** the signing key cannot be found. Module signing has been
  *** disabled for this build.
  make[1]: Entering directory `/usr/src/kernels/3.10.0-327.el7.x86_64'
    INSTALL /tmp/i40e-2.12.6/src/i40e.ko
    DEPMOD  3.10.0-327.el7.x86_64
  make[1]: Leaving directory `/usr/src/kernels/3.10.0-327.el7.x86_64'
  /sbin/depmod -e -F /lib/modules/3.10.0-327.el7.x86_64/source/System.map  -a 3.10.0-327.el7.x86_64
  Updating initramfs...
  make mandocs_install
  make[1]: Entering directory `/tmp/i40e-2.12.6/src'
  Copying manpages...
  make[1]: Leaving directory `/tmp/i40e-2.12.6/src'
  </code></pre>
  <p>what is the reason ? that we get the following errors:</p>
  <pre><code>common.mk:82: *** Kernel header files not in any of the expected locations.
  common.mk:83: *** Install the appropriate kernel development package, e.g.
  common.mk:84: *** kernel-devel, for building kernel modules and try again.  Stop.
  </code></pre>
  <p>reference - <a href="https://downloadcenter.intel.com/download/24411/Intel-Network-Adapter-Driver-for-PCIe-40-Gigabit-Ethernet-Network-Connections-Under-Linux-" rel="nofollow noreferrer">https://downloadcenter.intel.com/download/24411/Intel-Network-Adapter-Driver-for-PCIe-40-Gigabit-Ethernet-Network-Connections-Under-Linux-</a></p>