====== Arbor APS Upgrade Procedure ======
Basically, the upgrade firmware step was very similar with Arbor other product.

===== Upgrade Procedure =====
  * Use WebUI upload file to system disk.
    * Administration -> Files -> Upload File
    * Upload both arbos & Pravail-APS file.(EX: arbos-5.3-ECZG-i686 & Pravail-APS-5.5.1-ECZG)
    * Build code must be same with each other. (5.5.1 = ECZG, 5.5.0 = DKHC, 3.1.2 = DIIG, 3.1.0 = DFYD).
  * Check files were uploaded from command<code cmd>admin@arbos:/# system files directory disk
Directory listing of device disk:
  Filename                                  Kbytes Date/Time   Type
  Pravail-APS-5.5.1-ECZG                    207548 Jun23  2014 Signed package
  arbos-5.3-ECZG-i686                       106156 Jun23  2014 Signed package
  pravail_ssh_key.pub                            1 May26 19:01 Text file
  ssh_host.keys                                 10 May26 19:33 SSH host keys
Free space: 1.7G of 2.0G (14% used)</code>
  * Check system running file<code cmd>admin@arbos:/# system files show
 Installed packages:
  ArbOS_5.3            ArbOS 5.3 system files (build DKHC) (arch i686)
  Pravail-APS-5.5      Arbor Networks Pravail APS 5.5 (build DKHC) (arch i686)
admin@arbos:/# system files uninstall Pravail-APS-5.5</code>
  * Start Upgrade
    - Stop APS Service<code cmd>admin@arbos:/# services aps stop
Stopping Pravail APS services...done.
admin@arbos:/#</code>
    - Uninstall APS (get file name from # system files show)<code cmd>admin@arbos:/# system files uninstall Pravail-APS-5.5</code>
    - Install New ArborOS<code cmd>admin@arbos:/# system files install disk:arbos-5.3-ECZG-i686
Extracting package...done.
Changes to ArbOS will take effect after the next reload.</code>
    - Reboot APS<code cmd>admin@arbos:/# reload
  You are about to reboot the system.  Do you wish to proceed? [n] y
094: Rebooting the system..
...............</code>
    - Install APS (after reboot)<code cmd>admin@arbos:/# system files install disk:Pravail-APS-5.5.1-ECZG
Extracting package...done.
Collecting inventory information..done
Upgrading system (this may take some time).done.</code>
    - Start APS Service<code cmd>admin@arbos:/# services aps start
Starting Pravail APS services...................................done.
</code>