(1) We check all the SNMP configuration of S5700 are same and correct;
(2) And confirmed with customer that they say that they tried to change SNMP write community password on both sides(SW and esight )and manual SFTP manual data transfer(SW to esight) successfully.
(3)And analyzed the following logs and inforamtion:
we also didn't find any abnormal.
(4) At last, we captured the packets for troubleshooting, we found the root cause and resolved the problem. The root cause is the eSight server has 2 network cards with 2 IP address (10.201.129.210, 10.201.128.210). At the beginning, the 2 IP address can be reached from all devices, so when add devices to eSight server, some devices choose the IP address 10.201.128.210 as the source server IP address, but now, customer change his network, only IP address 10.201.129.210 is used to connect to devices, IP address 10.201.128.210 is used for users who wants to access eSight. So the IP address 10.201.128.210 is unreachable for devices. so these devices which used this IP address as source server IP address will backup configuration failed.
The root cause is the eSight server has 2 network cards with 2 IP address (10.201.129.210, 10.201.128.210). but there are not all used for devices.