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Cisco uBR10k PRE5

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Cisco uBR10k PRE5

Does anyone have experience with the PRE5 ?

Cisco website has hardware installation guides, but there are no configuration guides.

I don't have a uBR10k support contract any more, so couldn't hassle Cisco to provide me any information.

Information that I have discovered so far :

Each PRE5 has 4 x SFP+ ports for WAN backhaul

* Te0/0/0 - PRE-A, WAN backhaul 0
* Te0/0/1 - PRE-A, WAN backhaul 1
* Te0/0/2 - PRE-A, WAN backhaul 2
* Te0/0/3 - PRE-A, WAN backhaul 3

* Te0/1/0 - PRE-B, WAN backhaul 0
* Te0/1/1 - PRE-B, WAN backhaul 1
* Te0/1/2 - PRE-B, WAN backhaul 2
* Te0/1/3 - PRE-B, WAN backhaul 3

With 10G license you can unshut only ports 0
With 20G license you can unshut ports 0,1
With 30G license you can unshut ports 0,1,2
With 40G license you can unshut ports 0,1,2,3

Each PRE5 has 4 x SFP+ ports for board-to-board (B2B) connection.
These are wired using short DAC cables.
Configuration happens automatically, there aren't any interfaces to configure or IPs to assign
DAC 0 links Te0/0/0 and Te0/1/0
DAC 1 links Te0/0/1 and Te0/1/1
DAC 2 links Te0/0/2 and Te0/1/2
DAC 3 links Te0/0/3 and Te0/1/3

You can check B2B status like this :
Router>show int ten0/0/0 b2b ?
counter B2B counters
status B2B link status

Router#test cr10k5 show radian


Now, I have some unsolved questions..... Can anyone please help me solve?

Cisco PRE5 datasheet says :
"Supports either load sharing or backup mode between the WAN backhaul interfaces on active and standby Cisco uBR10012 PRE5s.
Any pair of 10 Gigabit Ethernet interfaces can be configured as backup mode either on the same PRE5 or across PRE5s."

If you had 20G license, would you put these interfaces into a port-channel :
* Te0/0/0
* Te0/0/1
* Te0/1/0
* Te0/1/1
CMTS would share traffic across these ports?
20G max throughput?
Is there any special CLI configuration required?

If you had 20G license, would you put these interfaces into a port-channel :
* Te0/0/0
* Te0/0/1
* Te0/1/0
* Te0/1/1
Would CMTS would hold standby PRE ports down? How to enable that?
Or do you manually shut ports, add the "backup interface xxx" command to the backup ports, then unshut?

We ended up putting the 6x

We ended up putting the 6x ten gig port into a port-channel (3 from each PRE5), uplink to Juniper switch.

Traffic is evenly shared across the ports.

The B2B lights are blinking

The previous 12.4Gbps throughput limit we saw is now gone (with PRE4 / 20Gbps WAN uplink).

Cisco documentation says the

Cisco documentation says the PRE5 requires these items :

UBR10-PWR-AC-PLUS power supplies (3300W)

Note, these have 2 x power cords per power supply. You have to connect both cords for the power supply to come online.

The CMTS boot up and run PRE5s with the standard UBR10-PWR-AC (2400W) power supplies, but beware they probably do not have enough grunt to run a fully loaded chassis. Our Lab was 2 x PRE5 and 5 x 3G60 and it ran happily off 1 x UBR10-PWR-AC.

On a production box with 2 x PRE5 and 8 x 3G60, show env says about 912W per PEM. If you also had some HD SPA in there, I reckon you are going to need the 3300W power supplies to be able to keep your H/A working.

UBR10012-FAN-PLUS fan tray

Again, we were able to successfully lab 2 x PRE5 with a standard tray UBR10-FAN-ASSY.

But I guess if you are going to load up the chassis in production, the newer fan tray is probably required for better cooling.

U-CHAS-COVER-EXT front cover or UBR10-FAN-FILT-E

Beware these U-CHAS-COVER-EXT stick out a long way (90mm).
If your rack rails aren't set back nice and deep, you may have problems closing door on rack.

I haven't tried the UBR10-FAN-FILT-E alternative.

PRE5-HA-CABMG-KIT which comprises of
1 x PRE5-CAB-HOLDER (Attaches to LCD to route fiber cables for 2nd PRE5. Is nice, but you could certainly still operate without it.)
4 x CAB-PRE5-BTB (These are 10G DAC cables for interconnecting the 2 x PRE5)

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