Involved Products and Versions
S9300 V100R002
S9300 V100R006
Networking
None
Fault Symptom
The Eth-Trunk on a switch frequently goes Up and Down.
Cause Analysis
When the timeout mode for an Eth-Trunk in LACP mode to receive LACP packets is set to fast, Eth-Trunk flapping tends to occur on the S9300 running V100R006.
Troubleshooting Procedure
Step 1 Run the display trapbuffer command to view alarm information on the switch. It is found that the Eth-Trunk frequently goes Up and Down.
May 11 2017 10:24:07 Switch %TRUNK/4/TRUNKUP(l):Interface
Eth-Trunk6 has turned into UP state.
May 11 2017 10:23:55 Switch %TRUNK/4/TRUNKUP(l):Interface Eth-Trunk4 has
turned into UP state.
May 11 2017 10:23:51 Switch %IFNET/4/LINKNO_STATE(l):The line protocol on
the interface Vlanif49 has entered the UP state.
May 11 2017 10:23:51 Switch %IFNET/4/IF_STATE(l):Interface Vlanif49 has
turned into UP state.
May 11 2017 10:23:51 Switch %RM/4/IPV4_DEFT_RT_CHG(l):IPV4 default Route is
changed. (ChangeType=Delete,InstanceId=0,Protocol=Static,ExitIf=Unknown,Nexthop=121.234.103.1,Neighbour=0.0.0.0,Preference=60,Label=NULL,Metric=0)
May 11 2017 10:23:51 Switch %TRUNK/4/TRUNKDOWN(l):Interface Eth-Trunk6 has
turned into DOWN state.
May 11 2017 10:23:51 Switch %IFNET/4/LINKNO_STATE(l):The line protocol on
the interface Vlanif49 has entered the DOWN state.
May 11 2017 10:23:51 Switch %IFNET/4/IF_STATE(l):Interface Vlanif49 has
turned into DOWN state.
May 11 2017 10:23:32 Switch %TRUNK/4/TRUNKDOWN(l):Interface Eth-Trunk4 has
turned into DOWN state.
May 11 2017 10:22:19 Switch %TRUNK/4/TRUNKUP(l):Interface Eth-Trunk4 has
turned into UP state.
May 11 2017 10:22:03 Switch %TRUNK/4/TRUNKDOWN(l):Interface Eth-Trunk4 has
turned into DOWN state.
May 11 2017 10:21:30 Switch %CMD/4/SUPERLOGIN(l):User logged in.
(User=weihu, IpAddress=61.155.48.34, Level=3, LoginResult=Successful)
May 11 2017 10:20:31 Switch %TRUNK/4/TRUNKUP(l):Interface Eth-Trunk4 has
turned into UP state.
May 11 2017 10:20:13 YCDT-XJ-BS.MAN.S9306-1 %TRUNK/4/TRUNKDOWN(l):Interface
Eth-Trunk4 has turned into DOWN state.
May 11 2017 10:17:07 Switch %TRUNK/4/TRUNKUP(l):Interface Eth-Trunk4 has
turned into UP state.
May 11 2017 10:16:52 Switch %TRUNK/4/TRUNKDOWN(l):Interface Eth-Trunk4 has
turned into DOWN state.
May 11 2017 10:15:48 Switch %SHELL/4/TELNETFAILED(l):Failed to login through
telnet. (Ip=172.16.1.1, UserName=**, Times=2)
Step 2 Run the display cpu-defend statistics all command to view statistics on all packets sent to the CPU. It is found that LACP packets are discarded all the time. As a result, the Eth-Trunk flaps.
<Switch> display cpu-defend
statistics all
Statistics on mainboard:
--------------------------------------------------------------------------------
Packet Type
Pass(Packet/Byte) Drop(Packet/Byte)
Last-dropping-time
--------------------------------------------------------------------------------
lacp
36253
1236 10:29:17
Step 3 Run the display this command in the Eth-Trunk interface view. The lacp timeout fast configuration is found. Run the lacp timeout slow command to change the timeout mode to slow, so that the Eth-Trunk will not frequently go Up and Down.
----End
Conclusions and Suggestions
For the S9300 running V100R002 and V100R006, the fast mode may cause Eth-Trunk flapping. You are advised to upgrade the switch to V200R008 and install the latest patch.
