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FOCS limitation on CM's

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Anonymous (not verified)
FOCS limitation on CM's

I am running a FOCS server hooked to a CC8000 cmts. I am only seeing 50 CM's get an ip and the rest are in ranging complete state. Any information on where to find the place to set a higher limit or anythign on this would be great.

Thanks,
Mark

bealsm
I was messing around with

I was messing around with FOCS too before I decided I hated it and started building my own linux based software. I found a few quirks to the software that make it joy to deal with.

Before messing with the software, can you log into the CMTS and debug one of the modems that isn't coming up? It will probably show you exactly where in the sequence something is breaking.

If you can't do that (or even if you can), I'd first verify the levels and the SNR of the RF side. I have personally had issues like this where the return path on one leg of the plant was out of whack. It was solid enough for docsis to range the modems but packets were getting garbled which killed the dhcp handshakes.

From there, I would check your DHCP server to make sure your pool of addresses is large enough. Then I would check the tftp server to see if it is handing out files correctly. If you shut the service down, you can restart it from the command line and it will dump the transaction logs to stdout. When I was on the phone with an engineer trying to get this software up and running, he said that if anything is going to die and cause issues, it's going to be the tftp server.

FlipZ (not verified)
I checked in my sql db for

I checked in my sql db for logs. I picked out a mac of a modem that is stuck in ranging complete. I see a ton of the following lines.

Failed to Receive Periodic RNG-REQ up 1 from modem SID=0x1F25 MAC:00:1a:66:67:dc:ba

also got these also for all the modems i see in ranging complete mode.

R103.0 Unable to Successfully Range CM (00:1a:66:67:dc:ba). Retries Exhausted. Ranging Aborted. P=16 T=0 F=0.

What does this normally mean?

Thanks,
Mark

bealsm
The failed to Receive

The failed to Receive Periodic RNG-REQ means that the CMTS failed to get the heartbeat signal from the modem. So the modem is either no longer transmitting it or it's not making it back to the CMTS. The CMTS will only try to ping the modem so many times before it gives up on it, which is the second error.

I would personally check the return path in the plant. Are the modems that are having issues all on the same leg of the plant? What are the signal levels like for the rest of the modems.

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