Cable modem is online but CMTS uBR10K can't ping , check status on DHCP PNR , CNR available

[anhlt2568]

Hi every body ,
I am a Engineer IT operation CMTS , i have a trouble like the subject of topic : The cable modem is online but CMTS can't ping , so we can't get the infomation of PWR , Mer , ... cable modem via SNMP - command line "cable modem remote query" . when i check the status on DHCP PNR , CNR of MAC address cable modem , it is avaible . So what is the reason here ? The communication between CM - CMTS - PNR . The CPE of CM connect internet normal .

Some cable modems same network of interface Bundle are normal , no ACL is applied . The issues are in some cable modems, not at all . when i reset this cable modem , it comeback normal.
Please help me to check it , sr about not good English .

Some log :

10K-NGOCKHANH-04#show cable modem 80:29:94:bb:d1:7f
D
MAC Address IP Address I/F MAC Prim RxPwr Timing Num I
State Sid (dBmv) Offset CPE P
8029.94bb.d17f 172.38.194.79 C7/0/2/U0 online 9 5.00 1040 1 N

10K-NGOCKHANH-04#show cable modem 80:29:94:bb:d1:7f cpe
IP address MAC address Dual IP Device Class
100.66.194.101 f4f2.6d84.8c87 N Host

10K-NGOCKHANH-04#ping 172.38.194.79

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.38.194.79, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

10K-NGOCKHANH-04#ping 100.66.194.101

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 100.66.194.101, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms

10K-NGOCKHANH-04#show cable modem remote-query | include 8029.94bb.d17f
8029.94bb.d17f 0.0 0.0 0.0 0 YES 172.38.194.79

Thanks!

[Georg Pauwen]

Hello, 

what do you have configured as DHCP server, the CMTS, or an external device ?

[anhlt2568]

Hi guy ,

I send you some config relate with DHCP : 

==== On CMTS === 

10K-NGOCKHANH-04#show running-config interface bundle 1.3
Building configuration...

Current configuration : 232 bytes
!
interface Bundle1.3
description "Giganet-Home2"
ip address 100.66.192.1 255.255.240.0 secondary
ip address 172.38.192.1 255.255.240.0
cable source-verify dhcp
cable dhcp-giaddr policy
cable helper-address 172.20.53.228
end

10K-NGOCKHANH-04#ping 172.20.53.228 source 172.38.192.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.20.53.228, timeout is 2 seconds:
Packet sent with a source address of 172.38.192.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms

[Georg Pauwen]

Hello,

are all modems running the same firmware ?

Where do you have ToD configured ? If you have not done that yet, you could try and configure it on the CMTS:

service udp-small-servers max-servers no-limit
!
cable time-server

[anhlt2568]

Hi ,

Thanks for your reply , now i have already configed two command which you posted . But,After applied these command , no status change .  Do i need reset the session of these cable modems which have issued ?