Downgrade the OLT to an earlier version. After the OLT is successfully added to the U2000, the OLT data fails to be synchronized to the U2000. As a result, the OLT cannot be managed on the U2000.
Handling Procedure
Step 1 Check SNMP configurations.
snmp-agent target-host trap-hostname U2000_237 address 100.104.145.237 trap-paramsname public123
snmp-agent target-host trap-paramsname public123 v1 securityname public123
snmp-agent trap enable standard
snmp-agent trap source meth 0
snmp-agent community read public123
snmp-agent community write private123
Check the firewall enabling statue.
HT(config)#display sysman firewall
{ protocol-type<E><telnet,ssh,snmp> }:snmp
Command:
display sysman firewall snmp
Firewall is disabled
HT(config)#
If the firewall is enabled, add the NMS address to the whitelist.
MA5680T(config)# sysman firewall snmp enable
MA5680T(config)# display sysman firewall snmp
Firewall is enabled
Step 2 Configure an IP address allowed by the SNMP.
MA5680T(config)# sysman ip-access snmp 100.104.145.237 100.104.145.237
MA5680T(config)#display sysman ip-access snmp
IP-Access Table:
--------------------------------------------
Index Start-IPAddr End-IPAddr
--------------------------------------------
1 100.104.145.237 100.104.145.237
--------------------------------------------
Note: If all configurations are normal but data synchronization still fails, check OLT configurations such as the IP address and all routes. If the routes are normal, the U2000 server can be successfully pinged.
To add a static route if required for the check, run the IP route-static command.
Step 3 Suspect that the data synchronization fails because the TCP connection fails to be set up. As a result, the OLT cannot be pinged from the U2000 server, or OLT configurations cannot be backed up to the U2000 server.
In an attempt to back up the configurations, the system displays a message indicating that the server is unreachable.
Step 4 Capture packets on the U2000 server.
set up after a TCP connection is successfully set up.
Step 5 Configure the OLT for management through the upstream port. The configuration method is as follows:
1. Set the upstream Native VLAN to 200 (or to another VLAN ID).
HT(config)#port vlan 300 0/19 0
HT(config)#interface giu 0/19
HT(config-if-giu-0/19)#native-vlan
{ all<K>|portid<U><0,1> }:0 vlan 300
Command:
native-vlan 0 vlan 300
2. On the interface for VLAN 300 configuration, configure the management IP address of the OLT.
56(config)#interface vlanif 300
56(config-if-vlanif300)#
56(config-if-vlanif300)#
56(config-if-vlanif300)#ip address 1.1.1.1 23
{ <cr>|description<K>|sub<K> }:
Command:
ip address 1.1.1.1 23
56(config-if-vlanif300)#
Step 6 Capture packets by mirroring on the upstream port of the OLT.
Note: Mirror the packets of port 0/19/0 to a port on another upstream interface and ensure that the 2 ports are in the same VLAN so that the packets can be transmitted in between.
56(config)#mirror port src-port 0/19/0 dst-port 0/20/0
{ mirror-direction<E><ingress,egress,all> }:all
Command:
mirror port src-port 0/19/0 dst-port 0/20/0 all
! RUNNING MAJOR 2018-11-21 11:49+08:00
EVENT NAME :Configure the port mirror
PARAMETERS :Source frame ID: 0, Source slot ID: 19, Source port ID: 0,
Destination frame ID: 0, Destination slot ID: 20, Destination port ID: 0,
Mirror direction: all
56(config)#
Step 7 Query packet capture data.
According to the captured packets, the OLT does not reply to the last ACK packet. As a result, the three-way handshake fails.
Step 8 Analyze the cause why the OLT does not reply to the packet.
According to an analysis, it is found that the OLT considers that the received packet checksum is incorrect.
Root cause: The advanced option Checksum Offload of the network adapter of the U2000 server is enabled, causing a problem with the compatibility with the OLT. After the option is disabled, services are restored.
