Tech Note: ENCS, NFVIS and WAAS

Learning the hard way so you don’t have to.


When you deploy a Cisco ENCS 5400 appliance (specifically the 5412), there’s not a lot of clarity in the official Cisco documentation about the different modes. I hope if you’re looking for clarity, that this helps you get through your installation.

Let’s start at the beginning.

From a physical hardware perspective, the ENCS 5400 appliances have two different places for hard drives. They have an internal SSD (Figure 4)and two external 2.5" hard drive slots for SSD or HDD (Figure 6).

Internals of an ENCS 5412

When you purchase an ENCS 5412, you can load it with two versions of software: NFVIS or WAAS Appliance. Here are the differences:

  • NFVIS is the KVM-based (CentOS 7) virtualization environment maintained and supported by Cisco. Here is the download link for the latest revision that you can find on Cisco’s downloads site -> Routers -> Network Functions Virtualization -> Enterprise NFV Infrastructure Solution -> NFV Infrastructure Software. Once you load NFVIS, you can then configure NFVIS for a variety of networking options and load your choice of virtualization images (Linux, Windows, ISRv, etc.). I’ll refer to this as NFVIS + vWAAS. This image is loaded onto the internal SSD (Figure 4 above), and then the external drives are used for VM storage.
  • If you are using the ENCS as ONLY a WAAS appliance, there is a separate download that turns the system into a WAAS-only ENCS. It still runs NFVIS, but you don’t have any access to it and all the settings are pre-configured. You can find that download link on the WAAS download pages. I’ll refer to this as WAAS-only. This image is loaded onto the external SSDs (Figure 6 above), which must be configured in RAID 1.

WAAS-Only Installation and Operation Notes

Here’s what’s not listed in the documentation for the WAAS-only installation.

  • There are two ways that you can load new/upgraded software onto the system. You can configure the CIMC KVM and attach the ISO images via virtual media. This is the correct way to re-image the box.
  • You can connect a physical USB key that has the ISO images listed above to the front port, then use the CIMC interface to select the USB boot drive. THIS DOES NOT WORK. DO NOT DO THIS! If you try this, your installation will fail.
  • You MUST follow the instructions to configure CIMC to enable Serial Over LAN, then SSH to CIMC and type ‘connect host’ to get to the WAAS-only console. There is NO display on the screen or the virtual KVM. On this page, make sure you do Step 18.
  • When you load the WAAS-Only ISO, it’s done in a two-step process. Step 1 is when you vKVM boot the ISO image and it reformats the drive. After it reboots, you can pick the WAAS size that you’d like to install, but this is ONLY accessible through the Serial over LAN console.
  • Finally, you need to manually change the boot order in the CIMC BIOS so that the ENCS boots off the RAID 1 array, not the internal SSD. If you see a GRUB: Can’t find partition error and it dumps you in GRUB Rescue mode, your boot order is wrong. Here are the CIMC settings (Home -> Compute -> BIOS -> Configure Boot Order) required.
WAAS-Only Correct Boot Order
NFVIS Correct Boot Order
  • It is critical that the CIMC is online and accessible remotely for administration of the box in WAAS-Only mode in case the WAAS software becomes unresponsive/corrupted, etc.

Finally, the WAAS-Only networking needs the following network connections/connectivity:

  • Gig0/0 and Gig0/1 are configured directly in WAAS for WCCP/AppNav interception and map to Virtual 1/0 and Virtual 2/0 in the WAAS software.
  • MGMT CIMC is Ethernet access to CIMC.
  • The black CIMC port is a serial connection for a terminal server. The same output can be accessed from the CIMC SOL connection.

The benefit of running the ENCS in WAAS-Only mode is that you don’t need to manage the overhead of the NFVIS appliance for a single VM. With CIMC access, you could convert WAAS-Only mode to NFVIS+vWAAS at any point in the future.

Hope this helps if you’re trying to get vWAAS + NFVIS or ENCS WAAS-Only configured properly.

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