cmts arp packets

[gurcan_basural]

our cmts send ots of arp packets to cm from cable interface ip , my cmts cpu utilization like this:

CPU utilization for five seconds: 41% / 27%; one minute: 29%; five minutes: 28%

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

78 50489936 364082659 138 2.78% 1.89% 1.76% 0 IP Input

58 7189144 14929936 481 1.14% 0.42% 0.36% 0 CMTS MAC Timer P

22 12839632 47216178 271 0.24% 0.35% 0.37% 0 ARP Input

is anybody can sent those packets over cmts ?is it possible ?

at user pc you can see that: %99.8 arp packets arp traffic (ethereal )

we are using cisco element managemet framework .

how can ı stop that

[mchin345]

There is one issue with Linksys devices replying to all ARP requests sent in the downstream direction. Even with "cable arp"

disabled there might be cases where ARP input can take up some CPU cycles. This might happen when there are large number of Linksys CPEs connected to the CMTS.

When the CMTS sends an ARP request for an address belonging to a modem/CPE (maybe to rebuild the arp table for entries that are about to expire etc.), these Linksys devices might answer the ARP request even though it was not destined for them. If you have a lot of Linksys devices connected to the CMTS and you see high CPU utilization due to "ARP Input" process (even with cable arp disabled), try disabling "cable proxy-arp" to see if that helps bring down the CPU utilization.

Even if still there is no change, try upgrading to Cisco IOS 12.2(15)BC2e.

[unicmd]

hi there ...

had and still have the same problem with our 7114E. Try to look at your cable modem remote-query, if your running this command. It snmp pools every modem at the giving time + it arps all the modems before doing this.

Also look at arp timeout on your cable-interface. Try to ajust there 2 commands and look at your sh proc cpu his to see if it has an effect

/Martin

Denmark