Hi group.
I hope I can explain myself well.
We have one bsr1k working for our entire HFC plant. Now we want to add another cmts (an bsr2k) to manage one geographic zone. This geographic zone has no optical receiver, due to has no many users. What we did was to configure the second cmts with a different frecuency on downstream due to everybody shares the downstream. The original cmts (bsr1k) is working with 555Mhz on downstream and the new one (bsr2k) has 561Mhz (6 Mhz of difference). On upstream we think that there's nothing to do because physically is separated. The next step was to disconnect the upstream port 3 from the bsr1k and to connect it to the upstream port 0 of bsr2k. When we put all together to work, the cable modems were offline.
This is the sho run of the new cmts (the bsr2k).
cable spectrum-group grupo0
band 23000000 40000000
hop action frequency 36000000 priority 2
hop action roll-back
!
cable spectrum-group grupo1
band 23000000 40000000
hop action frequency 36000000 priority 2
hop action roll-back
!
cable spectrum-group grupo2
band 23000000 40000000
hop action frequency 36000000 priority 2
hop action roll-back
!
cable spectrum-group grupo3
band 23000000 40000000
hop action frequency 36000000 priority 2
hop action roll-back
cable downstream 0 frequency 561000000
cable downstream 0 modulation 64
cable downstream 0 power-level 500
cable downstream 0 rate-limit
no cable downstream 0 shutdown
cable upstream 0 channel-width 1600000
cable upstream 0 frequency 33600000
cable upstream 0 physical-delay automatic
cable upstream 0 spectrum-group grupo0
cable upstream 0/0 range-backoff 2 8
cable upstream 0 power-level 80
cable upstream 0/0 modulation-profile 2
cable upstream 0 rate-limit
no cable upstream 0 shutdown
no cable upstream 0/0 shutdown
We have to modify also the upstream freq. on the new cmts?
Please any help would be very nice
Thanks in advanced.
The show run doesn't have all the info, just the downstream and upstream. questions...
the dhcp server's setup for the 2nd cmts and different ip networks? it knows how to get to the new networks? how far does the modem go (dhcp (o), range completed) ?
modem files used, do they have downstream and upstream configured? example modem file set with 555 Mhz, it can't register with 561 Mhz downstream.
bpi configured? sntp server configured?
~Carl
Hi group
Thanks for the reply cmcaldas. Fortunely, we were able to put it to work. We had to configure new networks for the cable modems and differents frequencies for the cmts 1 and cmts 2. The problem were in the provisioning server. And we probed with three cable modems. Now we want to make a major change with near 200 cable modems. Now the question is how can I tell to modems, to catch the downstream frequency? When the three cable modem were online, we had to change the parameters on the cable modem's website. The cable modem will acquire that frequency by itself? do I have to write an script to put the frequency?
Thanks in advanced.
with only two downstream docsis channels, you don't need to have the modem file set with a given downstream channel. leave that and the upstream channel id blank. the modem will find the downstream and try to range upstream. if it can't talk to the cmts, it will go onto the next channel and then be able to register and go online.
I don't recommend do this with more than two downstream channels though. it would be best to narrow cast the downstream and use the same channel at that point. since your plant's not set up that way and only talking 200 modems, you'll be fine.
please keep the group posted should anyone else have the question in the future
~Carl
Hi group
I must say that until now everything is working good. The cmts 1 and cmts 2 are working now. One with a freq 555Khz and the other with 561Khz. With some modifications for the dhcpd to making work the different networks.
Now the check list is:
1- change freq on downstream
2- prepare dhcpd for new networks
3- enjoy
You're were right. The cable modems found their way by themself. It can have some delay (for me almost 1/2 hour). I hope this can be useful.
Thanks as always cmcaldas.
Thanks group.
A half hour seems too long, make sure the modems have current firmware, should be less than half that time for them to register.
Glad it worked out
Carl