| Attachment | Size |
|---|---|
 before.JPG | 130.5 KB |
| after.JPG | 132.77 KB |
| verbose_after.jpg | 97.06 KB |
| verbose_before.jpg | 108.21 KB |
 config.txt | 6.57 KB |
I am activating the first time a cmts ubr10k and something weird's happening to me. in a test probe at the headend I have a cable modem docsis 3.0 to get 8 downstream channels and 4 upstream channels. when active network the same cable modem takes the 8 downstream channels but only one upstream channel. checked signal, noise, etc. and it's all ok! attached documentation on these tests. someone could explain me what might be happening?
thank you.
to enabling upstream bondig you must do following steps
1- you must enable the "mtc mode" at config file
2- you must also enable the "mtc-mode" in mac domain
For example
for ubr10k
interface cable 8/0/0
cable mtc mode
3- you must create an upstream bonding group for upstream channels defined for fiber-node
for example
cable upstream bonding-group 8000
upstream 0
upstream 1
upstream 2
upstream 3
4- you must create a fiber-node configuration depending on your mac domain configuration
cable fiber-node 101
downstream Modular-Cable 8/0/0 rf-channel 0-11
upstream Cable 8/0 connector 0
5- all upstream channels must be defined at same upstream connector
cable upstream 0 connector 0
cable upstream 1 connector 0
cable upstream 2 connector 0
cable upstream 3 connector 0
thanks for the answer.
I see this issue of mtc in the configuration file but the rest I think it's all ok!
the problem is that if I put the cable modem docsis 3.0 in combiner alone he takes 8 down channels and 4 up.
Now when I connect the network with something around 350 cable modem 1.x and 2.0 the cable modem that same docsis 3.0 takes the 8 channels down but only 1 up channel.
Are the modems all landing on the same US channel? Or do they randomise across all 4?
What does your return path look like ? eg
1) node -> headend return receiver -> 4 way splitter -> 4 x CMTS upstream cables
2) node -> headend return receiver -> return combiner input -> return combiner output -> 4 way splitter -> 4 x CMTS upstream cables
3) node -> headend return receiver -> return combiner input -> 4 x return combiner outputs -> 4 x CMTS upstream cables
Thank you for your help. they are randomise across all 4. to better explain the situation to see the attached file.
the situation is real. It involves no optical equipment. with the return of receiver disconnected the cable modem 3.0 takes the 4 upstream channels. if I to connect the receiver return the cable modem 3.0 only takes an upstream channel.
I have another cmts ubr10k installed in another city with the same scheme of combining return that do not have this problem. including the return snr is not very well but takes the 4 upstream.
the difference is that in this city the processor board is PRE-2 and the problem is PRE-4.
If I understand you correctly, you have a mix of D1.x, D2.0 and D3.0 modems in this node? Hundreds of modems in total?
D3.0 modems are coming online in 8x1 mode? Both in the plant and in the lab?
However when you disconnect plant modems, and just test with a single D3.0 modem in the lab it will come on as 8x4 ?
The key thing to note here is I notice the D3.0 modem is running in a 1 channel bonding group. (This is different to 1 unbonded channel like used by D1.x and D2.0)
My guess is it probably is an admission control issue, where the CMTS is thinking it lacks capacity to service all 4 channels of the D3 modems, and thus is load-balancing the modem onto the auto-generated 1 channel bonding groups.
Do you have this command in your global running conf ? : cable load-balance docsis30-enable
If so, change it to : cable load-balance docsis30-enable downstream-only
(Note I believe this command requires IOS SCG6 or SCH1 or later)
Then try resetting some 8x1 modems and see if they back come online as 8x4
PS. If this is the fix for this brain teaser, then you owe me a beer LOL :-)
okay! all your statements are correct. this is exactly what happens.
I still have no modem on the network 3.0. I only have 2 cable modem that test lead. approximately have around 350 cable modem 2.0 and 1.x this return to connect.
surely pay a beer but unfortunately did tests following their suggestions and did not work. version of my ios is ubr10k4-k9p6u2-mz.122-33.SCF1.bin.
the command you suggested has not. see attached options. I was already on the command cable load-balance docsis30-enable.
excludes cable modem load balance and I disabled any load balance without success. please would you have other suggestions?
Perhaps try :
no cable load-balance docsis30-enable
Or upgrade the IOS so you can use :
cable load-balance docsis30-enable downstream-only
I have given this command no cable load-balance docsis30-enable. I even did a test disable any and all load balence without success. It includes 2 cable test modem to not participate in the load balance without success.
upgrade the ios it is already a bit more radical and I have no other version. I will continue trying to succeed post here. Thank you for your help.
Dear Mbowe
I managed to make a debug when the cable modem was registering 3.0. is that it can not give me any idea of what might be happening?
personally I'm still with this problem. completely discarded the reason being the load-balance as I disabled completely and not solved.
a test we did and took the 4 upstream channels was put 4 service flow in the configuration file. see attached file. the problem is that no balancing traffic. only out for upstream.
does anyone have any idea what might be happening? You can send a file that is working up to 4 test? the stranger got another ubr10k that picking up 4 up and the file has only one service flow.
thank you.