Hi everyone，
I will share a case about a smart meter connect an RJ485 Serial port of MA5621.
Product Model
MA5621
MA5621V800R312
Problem Description
A smart meter is connected to a serial port of MA5621, and the smart meter was frequently online and offline.
The data center found that a smart meter was frequently online and offline. Online 2 minutes offline 3 minutes then online.
Handling process
Topology：Smart meter connects with MA5621 by RS485, MA5621 connect OLT, Router, Firewall, F5 to the data center.
1.Checked the configuration of the MA5621, no abnormality was found.
2.Compared with another normal MA5621 configuration in the same scenario, no abnormality was found.
3.Replace the MA5621 port.
Change the smart meter from MA5621 0/2/0 to 0/2/1. After the serial connection is configured. the fault persists.
<serialop-config>
serialop-connection 1 port 0/2/1 working-mode TCP-client local-address
xxx.xxx.xxx.30 local-port xxx6 peer-address xxx.xxx.xxx.10 peer-port xxx6 frame-type
none
#
[prevlanif]
<prevlanif>
interface vlanifxxx //Management vlan of the MA5621
interface vlanifxxxx //Service vlan of the Smart meter
#
[vlanif]
<vlanifxxx>
interface vlanifxxx
ip address xxx.xxx.xxx.189 255.255.248.0 //Management IP address of the MA5621
#
<vlanifxxxx>
interface vlanifxxxx
ip address xxx.xxx.xxx.30 255.255.248.0 //Service IP address of the Smart meter
#
4.Run display serialop-connection
The TCP connection is intermittently disconnected, which occurs every few minutes.
huawei#display serialop-connection
{ all<K>|connectionid<U><1,4294967294>|statistics<K> }:1
Command:
display serialop-connection 1
Serialop-connection ID : 1
Serial port : 0/2/1
Mode : TCP-Server
Local Address : xxx.xxx.xxx.30
Local Port : xxx6
Peer Address : xxx.xxx.xxx.10
Peer Port : xxx6
Frame Type : none
RTU ID : 8888
Connect State : initialize
5.Ping the IP address of the data center from the MA5621.
The ping operation is intermittently interrupted, which occurs every few minutes.
It is suspected that the IP address of the smart meter configured on the MA5621 conflicts with the IP addresses configured on other devices, or packet loss occurs on the network.
Advise the customer to replace the IP address of the smart meter. If the fault persists after the replace service IP address, we will continue to check whether packet loss occurs on the network.
Replace the service IP address of the smart meter and ping the IP address of the data center. The test result is normal and no packet loss occurs. The TCP connection status is normal. The problem does not recur after one day of observation. After checking the network, it is found that the IP address (IP address before replacement)of this smart meter is the same as the management IP address of the other MDU.
Root Cause
The service IP address of the smart meter conflicts with the management IP address of another MDU.
Solution Description
Replace the service IP address of the smart meter.
Thanks.
