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Cisco ubr10k PRE4 - static modem-count loadbalancing - bonding change

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fschlums
Cisco ubr10k PRE4 - static modem-count loadbalancing - bonding change

Anybody out there ever set up Docsis30 Loadbalancing based on Cisco modem-count loadbalancing?
The command "cable load-balance docsis30-enable" was introduced in IOS SCF.
Now i would like to use the 'dynamic bonding change' for D30 modem. So far I've set up the following:

cable load-balance docsis30-enable
!
cable load-balance docsis-group FN 3 MD Cable6/0/1
no disable
method utilization us-method utilization
interval 30
threshold load 10
threshold load minimum 3
threshold stability 50
no policy ugs
threshold ugs 70
no policy pcmm
threshold pcmm 70
no policy us-across-ds
no policy pure-ds-load
init-tech-list 1-4
docsis-policy 0
!
interface Cable6/0/1
description DS:410-466MHz
downstream Modular-Cable 6/0/0 rf-channel 4-10 upstream 0
cable tftp-enforce
no cable mtc-mode
cable service type VOD
no cable packet-cache
cable bundle 2
...
!
interface Modular-Cable6/0/0:4
cable bundle 2
cable rf-bandwidth-percent 6
!
interface Wideband-Cable6/0/0:1
description TEST 3G60 VOD
cable bundle 2
cable rf-channel 4 bandwidth-percent 45 remaining ratio 100
cable rf-channel 5
cable rf-channel 6
cable rf-channel 7
!
interface Wideband-Cable6/0/0:2
description TEST 3G60 VOD
cable bundle 2
cable rf-channel 4 bandwidth-percent 45 remaining ratio 100
cable rf-channel 8
cable rf-channel 9
cable rf-channel 10
!
cable fiber-node 3
description TEST 3G60 VOD
downstream Modular-Cable 6/0/0 rf-channel 4-10
upstream Cable 6/0 connector 0
!

Is there a way to balance D30 modems between these two wideband-interfaces? There would be no need to change the primary channel.
Can anybody tell me how to verify the dynamic bonding change feature?

mbowe
I reckon load-balance is the

I reckon load-balance is the most complex Cisco CMTS topic !

First suggestion, upgrade to the latest IOS possible. I know there were load-balance bugs in SCF2 and prior. Probably a recent SCG would be a good choice. And if you are super keen I know Cisco have built some substantial load-balance improvements into SCH1 (have a look at the release notes).

Next, I am a little bit confused about your primary channels. From your message I get the feeling you think that channel 4 is the only primary? That isn't the case. All DS channels you put into "interface cable" stanza are primary.

If a modem registers with primary as DS4 then probably the two bonding groups would be eligible. But that is only a 1 in 7 chance of happening. If a modem registers to one of the other channels then you cant then balance between the two groups. You will be locked to the group related to the primary DS.

From memory, when there is more than one "equally good" bonding group available for your primary DS then D3 modems should automatically be spread/hashed across these groups at registration.

fschlums
hello mbowe, thanks for your

hello mbowe, thanks for your reply. You were right about the cable interface rf-channels. It's a typo from former tests. The line should be

downstream Modular-Cable 6/0/0 rf-channel 4 upstream 0

So only rf-channel 4 should work as a primary. All remaining channels 5-10 build two wideband interfaces with the same capacity.
And so far if I reboot my 20 testmodems they gonna be modem-count balanced over these two groups. It looks ok so far.

but now I would like to reach a utilization based balancing over these two wideband interfaces. So if wideband interface 1 has a load around 70% and the other around 20% some modem should switch the wideband rf-channels. (maybe from channels 4,5,6,7 to 4,8,9,10) In my eyes that would be a bonding change isn't it? The primary remains the same.

fschlums
static modem-count d30 balancing

An other sample I would like to discuss. Still the same Cisco Hardware and some D30 4x4 Modem.
Now I have a setup with 12 rf-channels and I would like three groups of 4 rf-channels. Every group has a primary channel rf-channel 0 4 and 8.
A modem-count based balancing would need an init0 setup. But that is ok.

How could a setup look like to create such three groups? And what about load balancing?

a sample:

cable load-balance docsis-enable
cable load-balance docsis30-enable
cable load-balance d30-ggrp-default disable
!
!
cable load-balance docsis-group 5001
restricted
downstream Modular-Cable 5/0/0 rf-channel 0-11
upstream Cable5/0/0 0-1
tag DOCSIS30_TAG
!
cable load-balance docsis-group 5002
restricted
downstream Modular-Cable 5/0/0 rf-channel 0-11
upstream Cable5/0/0 1-2
tag DOCSIS30_TAG
!
interface Cable5/0/0
downstream Modular-Cable 5/0/0 rf-channel 0 upstream 0-5
downstream Modular-Cable 5/0/0 rf-channel 4 upstream 0-5
downstream Modular-Cable 5/0/0 rf-channel 8 upstream 0-5
...
!
!
interface Modular-Cable5/1/0:0
cable bundle 1
cable rf-bandwidth-percent 36 remaining ratio 100
!
interface Modular-Cable5/1/0:4
cable bundle 1
cable rf-bandwidth-percent 36 remaining ratio 100
!
interface Modular-Cable5/1/0:8
cable bundle 1
cable rf-bandwidth-percent 36 remaining ratio 100
!
!
interface Wideband-Cable5/1/0:0
cable bundle 1
cable rf-channel 0 bandwidth-percent 20 remaining ratio 100
cable rf-channel 1 bandwidth-percent 20 remaining ratio 100
cable rf-channel 2 bandwidth-percent 20 remaining ratio 100
cable rf-channel 3 bandwidth-percent 20 remaining ratio 100
!
interface Wideband-Cable5/1/0:1
cable bundle 1
cable rf-channel 4 bandwidth-percent 20 remaining ratio 100
cable rf-channel 5 bandwidth-percent 20 remaining ratio 100
cable rf-channel 6 bandwidth-percent 20 remaining ratio 100
cable rf-channel 7 bandwidth-percent 20 remaining ratio 100
!
interface Wideband-Cable5/1/0:2
cable bundle 1
cable rf-channel 8 bandwidth-percent 20 remaining ratio 100
cable rf-channel 9 bandwidth-percent 20 remaining ratio 100
cable rf-channel 10 bandwidth-percent 20 remaining ratio 100
cable rf-channel 11 bandwidth-percent 20 remaining ratio 100
!
!
cable fiber-node 10
downstream Modular-Cable 5/0/0 rf-channel 0-11
upstream Cable 5/0 connector 0
!

What you think? Would that sample balance all 4x4 D30 modem count-based within the three wideband interfaces?

BTW: The two load-balance docsis-groups are only made to limit upstream bonding to two upstreams. Three or four pstreams together could reault in a rf problem.

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