Involved Products and Versions
All models and versions
Networking
The MSC device is directly connected to an NE router. After the cutover, the MSC device is directly connected to an S series switch, and packet loss occurs on the MSC device.
Fault Symptom
A large number of packets are discarded before and after the cutover.
Cause Analysis
After logs are checked, it is found that the auto-negotiated rate of the 1000M interface connecting the MSC device to the S series switch is only 10 Mbit/s, and the number of discarded packets exceeds the threshold. It is recommended that interfaces at both ends of a link work in non-auto-negotiation mode.
Troubleshooting Procedure
1. Log in to the S series switch, and run the display interface GigabitEthernet 0/0/5 command in any view to check the status of GE0/0/5 connected to the MSC device.
<HUAWEI> display
interface GigabitEthernet 0/0/5
GigabitEthernet0/0/5 current state : DOWN
Line protocol current state : DOWN
Description:
Switch Port, PVID : 3957, TPID : 8100(Hex), The Maximum Frame Length is 9216
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 0425-c597-4dc0
Current system time: 2017-11-01 18:29+01:00
Port Mode: COMMON COPPER, Transceiver: 1000_BASE_T_SFP
Speed : 1000, Loopback: NONE
Duplex: FULL, Negotiation: ENABLE //The interface works in
auto-negotiation mode.
Mdi : AUTO, Flow-control: DISABLE
Last 300 seconds input rate 0 bits/sec, 0 packets/sec
Last 300 seconds output rate 0 bits/sec, 0 packets/sec
Input peak rate 35877408 bits/sec, Record time: 2017-11-01 18:29
Output peak rate 33694256 bits/sec, Record time: 2017-11-01 18:29
Input: 102615936 packets, 31409886697 bytes
Unicast:
102595943, Multicast:
502
Broadcast:
19470,
Jumbo:
0
Discard:
0,
Pause:
0
Frames:
0
Total Error: 21
CRC:
12, Giants:
0
Jabbers:
0,
Fragments:
8
Runts:
0, DropEvents:
0
Alignments:
0,
Symbols:
1
Ignoreds:
0
Output: 127584698 packets, 34122796642 bytes
Unicast:
127511799,
Multicast:
1632
Broadcast:
71267,
Jumbo:
0
Discard:
127147932,
Pause:
0 //A large number of packets are discarded.
Total
Error:
0
Collisions: 0,
ExcessiveCollisions:
0
Late
Collisions:
0,
Deferreds:
0
Buffers
Purged:
0
Input bandwidth utilization threshold : 80.00%
Output bandwidth utilization threshold: 80.00%
Input bandwidth utilization : 0%
Output bandwidth utilization : 0%
2. Run the display logbuffer command in any view. The command output shows that GE0/0/5 frequently alternates between Up and Down.
<HUAWEI> display logbuffer
Logging buffer configuration and contents :
enabled
Allowed max buffer size :
1024
Actual buffer size :
512
Channel number : 4 , Channel name :
logbuffer
Dropped messages :
0
Overwritten messages :
0
Current messages : 109
Nov 1 2017 11:17:45+01:00 Utex-CS-S5300-1
%IFNET/4/LINK_STATE(l)[14]:The line protocol IP on the interface
GigabitEthernet0/0/5 has entered the DOWN state.
Nov 1 2017 11:17:45+01:00 Utex-CS-S5300-1 %IFPDT/4/IF_STATE(l)[15]:Interface
GigabitEthernet0/0/5 has turned into DOWN state.
Nov 1 2017 11:15:38+01:00 Utex-CS-S5300-1
%IFNET/4/LINK_STATE(l)[16]:The line protocol IP on the interface
GigabitEthernet0/0/5 has entered the UP state.
Nov 1 2017 11:15:38+01:00 Utex-CS-S5300-1
%IFPDT/4/IF_STATE(l)[17]:Interface GigabitEthernet0/0/5 has turned into UP
state.
Nov 1 2017 11:15:32+01:00 Utex-CS-S5300-1
%IFNET/4/LINK_STATE(l)[18]:The line protocol IP on the interface
GigabitEthernet0/0/5 has entered the DOWN state.
Nov 1 2017 11:15:32+01:00 Utex-CS-S5300-1
%IFPDT/4/IF_STATE(l)[19]:Interface GigabitEthernet0/0/5 has turned into DOWN
state.
Nov 1 2017 11:15:24+01:00 Utex-CS-S5300-1
%IFNET/4/LINK_STATE(l)[20]:The line protocol IP on the interface
GigabitEthernet0/0/5 has entered the UP state.
Nov 1 2017 11:15:06+01:00 Utex-CS-S5300-1
%IFPDT/4/IF_STATE(l)[21]:Interface GigabitEthernet0/0/5 has turned into UP
state.
Nov 1 2017 11:15:00+01:00 Utex-CS-S5300-1
%IFPDT/4/IF_STATE(l)[22]:Interface GigabitEthernet0/0/5 has turned into DOWN
state.
Nov 1 2017 11:12:07+01:00 Utex-CS-S5300-1
%IFPDT/4/IF_STATE(l)[23]:Interface GigabitEthernet0/0/5 has turned into UP
state.
3. Run the display diag-logfile buffer command in the diagnostic view to check diagnostic logs. The command output shows that the interface rate is negotiated to 10 Mbit/s when the status of GE0/0/5 is Up, and the number of discarded packets exceeds the threshold.
<HUAWEI> system-view
[HUAWEI] diagnose
[HUAWEI-diagnose] display diag-logfile buffer
... ...
Line 37198: Nov 1 2017 01:43:04.70.3+01:00 Utex-CS-S5300-1
%IFPDT/4/DUPLEX_HALF(D)[4174]:Interface GigabitEthernet0/0/5 duplex mode
log. (PhyStatus=DOWN, PreDuplex=FULL, CurrDuplex=HALF, Speed=0M,
Function=IFPDT_ChangePortStatus, Line=909)
Line 37199: Nov 1 2017 01:43:41.750.1+01:00 Utex-CS-S5300-1
%IFPDT/6/SYNC_NPTABLE(D)[4175]:Start syncing NP
table.(IfName=GigabitEthernet0/0/5, PortStatus=1,
Function=IFAGT_PortStatusToAllBoard, Line=1884)
Line 37200: Nov 1 2017 01:43:41.750.2+01:00 Utex-CS-S5300-1
%IFPDT/4/DUPLEX_HALF(D)[4176]:Interface GigabitEthernet0/0/5 duplex mode
log. (PhyStatus=UP, PreDuplex=FULL, CurrDuplex=FULL, Speed=10M,
Function=IFPDT_ChangePortStatus, Line=909)
Line 37209: Nov 1 2017 01:51:35.140.1+01:00 Utex-CS-S5300-1
%IFPDT/6/SYNC_NPTABLE(D)[4185]:Start syncing NP
table.(IfName=GigabitEthernet0/0/5, PortStatus=0,
Function=IFAGT_PortStatusToAllBoard, Line=1884)
Line 37210: Nov 1 2017 01:51:35.140.2+01:00 Utex-CS-S5300-1
%IFPDT/4/DUPLEX_HALF(D)[4186]:Interface GigabitEthernet0/0/5 duplex mode
log. (PhyStatus=DOWN, PreDuplex=FULL, CurrDuplex=HALF, Speed=0M,
Function=IFPDT_ChangePortStatus, Line=909)
Line 37211: Nov 1 2017 01:52:20.410.2+01:00 Utex-CS-S5300-1
%IFPDT/6/SYNC_NPTABLE(D)[4187]:Start syncing NP table.(IfName=GigabitEthernet0/0/5,
PortStatus=1, Function=IFAGT_PortStatusToAllBoard, Line=1884)
4. Attempt to configure GE0/0/5 on the S series switch to work in non-auto-negotiation mode and forcibly work at 1000 Mbit/s. In addition, the interface on the peer device also works in non-auto-negotiation mode, and the problem is resolved.
<HUAWEI> system-view
[HUAWEI] intface GigabitEthernet 0/0/5
[HUAWEI-GigabitEthernet0/0/5] undo negotiation auto
[HUAWEI-GigabitEthernet0/0/5] speed 1000
Conclusions and Suggestions
Interfaces at both ends of a link must use the same negotiation mode. If they use different negotiation modes, for example, the local device works in non-auto-negotiation mode and the peer device works in auto-negotiation mode, the local interface may be Up or Down, but the peer interface is always Down. If two connected interfaces work in non-auto-negotiation mode, you need to configure the same interface rate for them.