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Clear modem CPE table MIB?

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Anonymous (not verified)
Clear modem CPE table MIB?

Is there a MIB out there that can clear the CPE table on a cable modem? I'm not trying to clear the entry on the cmts table, I'm talking on the cable modem itself. What I want to be able to do is clear the CPE entries from the modem, so a new CPE can be put in place without power cycling the cable modem. Basically cause the modem to "forget" what is connected to it.

Anonymous (not verified)
Clear modem CPE table MIB?

Anybody ever heard of anything like this?

Clear modem CPE table MIB?

I am not aware of any MIB that will clear the CPE table.
Power cycle the modem

Clear modem CPE table MIB?

Reset the modem

you can do it with snmp also

snmpset -v1 -c "community" i 1

Anonymous (not verified)
Clear modem CPE table MIB?

Well, we're kinda looking to use it for our voip customers who also use the modem for internet service. We dont want to have to disconnect the phone call to reset the modem, call customer back, verify, etc. We'd like to be able to clear table and simply have the customer reboot the CPE.

Clear modem CPE table MIB?

There is no Docsis standard MIB to do such things but I believe motorola and toshiba modems have a private vendor specific mib that have these capabilities.

The DOCSIS standard specifically states that the entries are supposed to stay in this table until reboot.

I imagine you need this for troubleshooting purposes, i.e. please disconnect your vonage router and hook up your pc directly to the cable modem type of thing...

Perhaps a different/better approach to this would be to increase the maxCPE on the modem and control DHCP a little differently. Or set the Max cpe in the config file to say two but on the cmts (cisco) set it to one. Then for these specific customers set it to two temporarily.

Our approach to this is two fold we auth all devices connected to cable modem and set max cpe to 4. Our Dhcp server automatically adds clients for modems we have authorized up to two per customer. So once we auth the modem during setup. The system automatically adds the clients in to dhcp until there are two on the account. Those that have two devices on their account already and try to add a third, are given a non-routeable ip and directed to a webpage telling them what the problem is and encouraging them to call Tech Support to switch out their clients.

Anonymous (not verified)
Clear modem CPE table MIB?

Well, we charge for additional IP's, so we don't really want to increase the max CPE on the modem side. Where can I find some info on these vendor specific MIBs? I tried searching but didn't come up with anything.

Your DHCP method is a good idea, but we are a very large ISP (I don't want to say which, but you can probably guess), and therefore I don't think it would be the best method for us.

Have you tried

Have you tried administratively turning off the Ethernet interface and then turning it back on via snmp? May be a way around resetting the cpe table on the Cable modem. Have not tried it but it may work.

I opened a case with

I opened a case with Motorola about this -- the short answer is no. There is just no way to clear out the bridge table on the CM with out reseting it. And that's part of the spec.

That said, my CM health script does query the bridge table for the MAC and also queries the dhcpd.leases file for leases from that CM. Sometimes it's helps identify if the subscriber swapped CPE without power-cycling (i.e. they tried out their Xbox now their Linksys router won't grab an IP). Querying the bridge table is also a handy way to see if the CPE is "seeable" by the CM without DHCP having occurred or even the CMTS knowing about it. If the Ethernet interface on the CM is up but I see no MAC address in the bridge table then I know that the CPE is not properly communicating.


If you have a Cisco is the answer

in a cisco CMTS environment:

CMTS_Prompt# clear cable host [cpe MAC] (enter)

You're talking about the "Learned MAC" that the CM holds to maintain the
number of CPEs as taught by the config file. By using this command, the
end-user can swap PCs and yet the cable operator knows that only 1 CPE
is getting online.

c ya!


Carlos: The best of my


The best of my knowledge, the CM also keeps track of the number of CPE. You may be able to clear it out on the CMTS (or override it, as both Cisco and Moto allow you to do), but if the CM's bridge table has one learned MAC and it's set for one, that's all you'll be able to do.



Anybody knows a way to issue a "clear cable modem IP reset" somehow to the cmts ? Is there a method of telling this via snmp ?
Sorry for the stupid question.

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