排除ASR 1000系列服務路由器上的資料包丟棄故障
簡介
本文檔介紹如何對Cisco ASR 1000系列聚合服務路由器上的丟包問題進行故障排除。
必要條件
需求
本文件沒有特定需求。
採用元件
本文中的資訊係根據以下軟體和硬體版本：
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所有Cisco ASR 1000系列聚合服務路由器，包括1002、1004和1006
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支援Cisco ASR 1000系列聚合服務路由器的Cisco IOS® XE軟體版本2.3.x及更高版本
本文中的資訊是根據特定實驗室環境內的裝置所建立。文中使用到的所有裝置皆從已清除（預設）的組態來啟動。如果您的網路運作中，請確保您瞭解任何指令可能造成的影響。
慣例
如需文件慣例的詳細資訊，請參閱思科技術提示慣例。
ASR 1000系列路由器的資料包流
高級資料包流
Cisco ASR 1000系列路由器在系統中包含以下功能元素：
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Cisco ASR 1000系列路由處理器1(RP1)
-
Cisco ASR 1000系列嵌入式服務處理器(ESP)
-
Cisco ASR 1000系列SPA介面處理器(SIP)
Cisco ASR 1000系列路由器引入Cisco QuantumFlow處理器(QFP)作為其硬體架構。在基於QFP的體系結構中，所有資料包都通過ESP轉發，因此，如果ESP出現問題，則轉發停止。
圖1 Cisco ASR 1006系統，帶雙路由處理器、雙ESP和三個SIP
有關詳細資訊，請參閱Cisco ASR 1000系列聚合服務路由器。
Cisco ASR 1000系列服務路由器上的資料包丟棄故障排除步驟
丟包點
Cisco ASR 1000系列路由器構建於路由處理器(RP)、嵌入式服務處理器(ESP)、SPA介面處理器(SIP)和共用埠介面卡(SPA)之上。 通過每個模組上的ASIC轉發所有資料包。
圖2 Cisco ASR 1000系列系統的資料路徑圖
Cisco ASR 1000系列路由器上有多個表1所示的資料包丟棄點。
表1封包捨棄點
| 模組 |
功能元件 |
|---|---|
| SPA |
取決於介面型別 |
| SIP |
IO控制處理器(IOCP)SPA彙總ASIC互連ASIC |
| ESP |
Cisco QuantumFlow處理器(QFP)轉發控制處理器(FECP)互連ASIC QFP子系統。QFP子系統由以下元件組成：
|
| RP |
Linux共用記憶體輸入介面(LSMPI)互連ASIC |
獲取有關丟包的資訊
如果遇到意外的丟包，您必須確保控制檯輸出、資料包計數器的差異以及重現步驟都可用於故障排除。為了確定原因，第一步是獲取儘可能多的有關問題的資訊。需要提供以下資訊來確定問題的原因：
-
控制檯日誌 — 有關詳細資訊，請參閱為控制檯連線應用正確的終端模擬器設定。
-
系統日誌資訊 — 如果已經將路由器設定為將日誌傳送到系統日誌伺服器，則可以獲取有關發生情況的資訊。如需詳細資訊，請參閱如何設定系統日誌的思科裝置。
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show platform - show platform命令顯示RP、ESP、SPA和電源的狀態。
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show tech-support - show tech-support 命令是許多不同命令的集合，包括show version 和show running-config。 當路由器遇到問題時，思科技術協助中心(TAC)工程師通常會要求您提供此資訊來排解硬體問題。執行重新載入或重新通電之前，您必須先收集這些技術支援，因為這些行動可能會導致有關問題的資訊遺失。
附註：show tech-support命令不包括show platform或show logging命令。
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重現步驟（如果可用） — 重現問題的步驟。如果無法複製，請檢查資料包丟棄時的條件。
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SPA計數器信息 — 請參閱SPA計數器部分。
-
SIP計數器資訊 — 請參閱SIP計數器部分。
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ESP計數器信息 — 請參閱ESP計數器部分。
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RP計數器信息 — 請參閱RP計數器部分。
收集計數器資訊的命令清單
有許多特定於平台的命令可用於排除資料包轉發故障。如果您開啟TAC服務請求，請收集這些命令。為了識別計數器的差異，請多次收集這些命令。粗體字元命令對開始故障排除特別有用。exclude _0_ 選項可有效使計數器排除0。
SPA
show interfaces
SIP
show platform hardware port <slot/card/port> plim statistics
show platform hardware subslot {slot/card} plim statistics
show platform hardware slot {slot} plim statistics
show platform hardware slot {0|1|2} plim status internal
show platform hardware slot {0|1|2} serdes statistics
ESP
show platform hardware slot {f0|f1} serdes statistics
show platform hardware slot {f0|f1} serdes statistics internal
show platform hardware qfp active bqs 0 ipm mapping
show platform hardware qfp active bqs 0 ipm statistics channel all
show platform hardware qfp active bqs 0 opm mapping
show platform hardware qfp active bqs 0 opm statistics channel all
show platform hardware qfp active statistics drop | exclude _0_
show platform hardware qfp active interface if-name <Interface-name> statistics
show platform hardware qfp active infrastructure punt statistics type per-cause | exclude _0_
show platform hardware qfp active infrastructure punt statistics type punt-drop | exclude _0_
show platform hardware qfp active infrastructure punt statistics type inject-drop | exclude _0_
show platform hardware qfp active infrastructure punt statistics type global-drop | exclude _0_
show platform hardware qfp active infrastructure bqs queue output default all
show platform hardware qfp active infrastructure bqs queue output recycle all
!--- The if-name option requires full interface-name
RP
show platform hardware slot {r0|r1} serdes statistics
show platform software infrastructure lsmpi
SPA計數器
對SPA和其他平台使用通用資料包丟棄故障排除。clear counters 命令可用於查詢計數器的差異。
若要顯示路由器上配置的所有介面的統計資訊，請使用以下命令：
Router#show interfaces TenGigabitEthernet 1/0/0
TenGigabitEthernet1/0/0 is up, line protocol is up
Hardware is SPA-1X10GE-L-V2, address is 0022.5516.2040 (bia 0022.5516.2040)
Internet address is 192.168.1.1/24
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Full Duplex, 10000Mbps, link type is force-up, media type is 10GBase-LR
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:59, output 00:00:46, output hang never
Last clearing of "show interface" counters never
Input queue: 0/375/415441/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
510252 packets input, 763315452 bytes, 0 no buffer
Received 3 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
55055 packets output, 62118229 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 pause output
0 output buffer failures, 0 output buffers swapped out
要顯示根據協定的資料包的統計資訊，請使用以下命令：
Router#show interfaces TenGigabitEthernet 1/0/0 accounting
TenGigabitEthernet1/0/0
Protocol Pkts In Chars In Pkts Out Chars Out
Other 15 900 17979 6652533
IP 510237 763314552 37076 55465696
DEC MOP 0 0 1633 125741
ARP 15 900 20 1200
CDP 0 0 16326 6525592
為了顯示已進行進程交換、快速交換或分散式交換的資料包的統計資訊，請使用以下命令：
Router#show interfaces TenGigabitEthernet 1/0/0 stats
TenGigabitEthernet1/0/0
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 15 900 17979 6652533
Route cache 0 0 0 0
Distributed cache 510252 763315452 55055 62118229
Total 510267 763316352 73034 68770762
SIP計數器
Cisco ASR 1000系列SIP不參與資料包轉發。它將SPA置於系統中。SIP為來自SPA的輸入封包提供封包優先順序，並為等待傳輸至ESP以進行處理的輸入封包提供大型輸入突發吸收緩衝區。出口緩衝在流量管理器上集中，並且還以SIP上的出口隊列的形式提供。Cisco ASR 1000系列路由器不僅可在ESP級別確定流量的優先順序，而且可以通過配置入口和出口分類來設定整個系統的流量優先順序。緩衝（入口和出口）與往返於ESP的背壓一起提供在系統中以處理超訂用。
圖3 Cisco ASR 1000系列路由器入口隊列
圖4 SIP框圖
若要顯示SPA彙總ASIC上的每個埠隊列丟棄計數器，請使用以下命令：
Router#show platform hardware port 1/0/0 plim statistics
Interface 1/0/0
RX Low Priority
RX Drop Pkts 0 Bytes 0
RX Err Pkts 0 Bytes 0
TX Low Priority
TX Drop Pkts 0 Bytes 0
RX High Priority
RX Drop Pkts 0 Bytes 0
RX Err Pkts 0 Bytes 0
TX High Priority
TX Drop Pkts 0 Bytes 0
若要顯示SPA彙總ASIC上的每個SPA計數器，請使用以下命令：
Router#show platform hardware subslot 1/0 plim statistics
1/0, SPA-1XTENGE-XFP-V2, Online
RX Pkts 510252 Bytes 763315452
TX Pkts 55078 Bytes 62126783
RX IPC Pkts 0 Bytes 0
TX IPC Pkts 0 Bytes 0
若要顯示SPA彙總ASIC上的所有SPA計數器，請使用以下命令：
Router#show platform hardware slot 1 plim statistics
1/0, SPA-1XTENGE-XFP-V2, Online
RX Pkts 510252 Bytes 763315452
TX Pkts 55078 Bytes 62126783
RX IPC Pkts 0 Bytes 0
TX IPC Pkts 0 Bytes 0
1/1, SPA-5X1GE-V2, Online
RX Pkts 42 Bytes 2520
TX Pkts 65352 Bytes 31454689
RX IPC Pkts 0 Bytes 0
TX IPC Pkts 0 Bytes 0
1/2, Empty
1/3, Empty
為了在SPA聚合ASIC上顯示到/來自互聯ASIC的聚合rx/tx計數器，請使用此命令。Rx計數器表示來自SPA的輸入資料包；tx計數器表示將資料包輸出到SPA。
Router#show platform hardware slot 1 plim status internal
FCM Status
XON/XOFF 0x0000000F00000000
ECC Status
Data Path Config
MaxBurst1 256, MaxBurst2 128, DataMaxT 32768
Cal Length RX 0x0002, TX 0x0002
Repetitions RX 0x0010, TX 0x0010
Data Path Status
RX in sync, TX in sync
Spi4 Channel 0, Rx Channel Status Starving, Tx Channel Status Starving
Spi4 Channel 1, Rx Channel Status Starving, Tx Channel Status Starving
RX Pkts 510294 Bytes 765359148
TX Pkts 120430 Bytes 94063192
Hypertransport Status
RX Pkts 0 Bytes 0
TX Pkts 0 Bytes 0
要顯示SIP互聯ASIC上ESP互聯ASIC的rx計數器，請使用以下命令：
Router#show platform hardware slot 1 serdes statistics
From Slot F0
Pkts High: 0 Low: 120435 Bad: 0 Dropped: 0
Bytes High: 0 Low: 94065235 Bad: 0 Dropped: 0
Pkts Looped: 0 Error: 0
Bytes Looped 0
Qstat count: 0 Flow ctrl count: 196099
ESP計數器
ESP提供集中轉發引擎，負責大部分資料平面處理任務。通過Cisco ASR 1000系列路由器的所有網路流量均通過ESP。
圖5 ESP的框圖
圖6 Cisco QuantumFlow處理器基本架構
如需詳細資訊，請參閱Cisco 1000系列聚合服務路由器。
要顯示ESP互連ASIC上RP、SIP互連ASIC的rx計數器，請使用以下命令：
Router#show platform hardware slot F0 serdes statistics
From Slot R0
Pkts High: 70328 Low: 13223 Bad: 0 Dropped: 0
Bytes High: 31049950 Low: 10062155 Bad: 0 Dropped: 0
Pkts Looped: 0 Error: 0
Bytes Looped 0
Qstat count: 0 Flow ctrl count: 311097
From Slot 2
若要顯示內部連結封包計數器和錯誤計數器，請使用以下命令：
Router#show platform hardware slot F0 serdes statistics internal
Network-Processor Link:
Local TX in sync, Local RX in sync
From Network-Processor Packets: 421655 Bytes: 645807536
To Network-Processor Packets: 83551 Bytes: 41112105
RP/ESP Link:
Local TX in sync, Local RX in sync
Remote TX in sync, Remote RX in sync
To RP/ESP Packets: 421650 Bytes: 645807296
Drops Packets: 0 Bytes: 0
From RP/ESP Packets: 83551 Bytes: 41112105
Drops Packets: 0 Bytes: 0
若要檢查輸入封包模組(IPM)通道和其他元件的對應，請使用以下命令：
Router#show platform hardware qfp active bqs 0 ipm mapping
BQS IPM Channel Mapping
Chan Name Interface Port CFIFO
1 CC3 Low SPI1 0 1
2 CC3 Hi SPI1 1 0
3 CC2 Low SPI1 2 1
若要顯示輸入封包模組(IPM)中每個通道的統計資訊，請使用以下命令：
Router#show platform hardware qfp active bqs 0 ipm statistics channel all
BQS IPM Channel Statistics
Chan GoodPkts GoodBytes BadPkts BadBytes
1 - 0000000000 0000000000 0000000000 0000000000
2 - 0000000000 0000000000 0000000000 0000000000
3 - 0000000000 0000000000 0000000000 0000000000
若要檢查輸出封包模組(OPM)通道和其他元件的對應，請使用以下命令：
Router#show platform hardware qfp active bqs 0 opm mapping
BQS OPM Channel Mapping
Chan Name Interface LogicalChannel
0 CC3 Low SPI1 0
1 CC3 Hi SPI1 1
2 CC2 Low SPI1 2
若要顯示輸出封包模組(OPM)中每個通道的統計資訊，請使用以下命令：
Router#show platform hardware qfp active bqs 0 opm statistics channel all
BQS OPM Channel Statistics
Chan GoodPkts GoodBytes BadPkts BadBytes
0 - 0000000000 0000000000 0000000000 0000000000
1 - 0000000000 0000000000 0000000000 0000000000
2 - 0000000000 0000000000 0000000000 0000000000
若要顯示封包處理器引擎(PPE)中所有介面的捨棄統計資訊，請使用以下命令。
附註：此命令在用於排除故障時很有用。
Router#show platform hardware qfp active statistics drop
----------------------------------------------------------------
Global Drop Stats Octets Packets
----------------------------------------------------------------
AttnInvalidSpid 0 0
BadDistFifo 0 0
BadIpChecksum 0 0
若要清除封包處理器引擎(PPE)中所有介面的捨棄統計資訊，請使用以下命令。此命令在顯示計數器後被清除。
Router#show platform hardware qfp active statistics drop clear
----------------------------------------------------------------
Global Drop Stats Octets Packets
----------------------------------------------------------------
AttnInvalidSpid 0 0
BadDistFifo 0 0
BadIpChecksum 0 0
若要顯示封包處理器引擎(PPE)中每個介面的捨棄統計資訊，請使用以下命令。此計數器每10秒清除一次。
Router#show platform hardware qfp active interface if-name TenGigabitEthernet1/0/0 statistics Platform Handle 6 ---------------------------------------------------------------- Receive Stats Octets Packets ---------------------------------------------------------------- Ipv4 0 0 Ipv6 0 0!--- The if-name option requires full interface-name
若要檢查將封包傳送到RP的原因，請使用以下命令：
Router#show platform hardware qfp active infrastructure punt statistics type per-cause
Global Per Cause Statistics
Number of punt causes = 46
Per Punt Cause Statistics
Packets Packets
Counter ID Punt Cause Name Received Transmitted
------------------------------------------------------------------------
00 RESERVED 0 0
01 MPLS_FRAG_REQUIRE 0 0
02 IPV4_OPTIONS 0 0
要顯示丟棄資料包（ESP到RP）的丟棄統計資訊，請使用以下命令：
Router#show platform hardware qfp active infrastructure punt statistics type punt-drop
Punt Drop Statistics
Drop Counter ID 0 Drop Counter Name PUNT_NOT_ENABLED_BY_DATA_PLANE
Counter ID Punt Cause Name Packets
----------------------------------------------------------
00 RESERVED 0
01 MPLS_FRAG_REQUIRE 0
02 IPV4_OPTIONS 0
為了顯示注入資料包（RP到ESP）的丟棄統計資訊，請使用此命令。插入資料包從RP傳送到ESP。它們大多由IOSD產生。它們是L2保持連線、路由協定、管理協定（如SNMP）等。
Router#show platform hardware qfp active infrastructure punt statistics type inject-drop
Inject Drop Statistics
Drop Counter ID 0 Drop Counter Name INJECT_NOT_ENABLED_BY_DATA_PLANE
Counter ID Inject Cause Name Packets
-------------------------------------------------------------
00 RESERVED 0
01 L2 control/legacy 0
02 CPP destination lookup 0
要顯示全域性丟棄資料包的統計資訊，請使用以下命令：
Router#show platform hardware qfp active infrastructure punt statistics type global-drop
Global Drop Statistics
Counter ID Drop Counter Name Packets
------------------------------------------------------------------
00 INVALID_COUNTER_SELECTED 0
01 INIT_PUNT_INVALID_PUNT_MODE 0
02 INIT_PUNT_INVALID_PUNT_CAUSE 0
要顯示每個介面的緩衝、排隊和排程(BQS)的預設隊列/排程的統計資訊，請使用以下命令：
Router#show platform hardware qfp active infrastructure bqs queue output default all
Interface: internal0/0/rp:0, QFP if_h: 1, Num Queues/Schedules: 2
Queue specifics:
Index 0 (Queue ID:0x2f, Name: )
Software Control Info:
(cache) queue id: 0x0000002f, wred: 0x88b002d2, qlimit (bytes): 6250048
parent_sid: 0x232, debug_name:
sw_flags: 0x00000011, sw_state: 0x00000001
orig_min : 0 , min: 0
orig_max : 0 , max: 0
share : 1
Statistics:
tail drops (bytes): 77225016 , (packets): 51621
total enqs (bytes): 630623840 , (packets): 421540
queue_depth (bytes): 0
要顯示每個介面的循環隊列/緩衝、排隊和排程(BQS)的統計資訊，請使用此命令。循環隊列儲存由QFP多次處理的資料包。例如，分段資料包和組播資料包放置在這裡。
Router#show platform hardware qfp active infrastructure bqs queue output recycle all
Recycle Queue Object ID:0x3 Name:MulticastLeafHigh (Parent Object ID: 0x2)
plevel: 1, bandwidth: 0 , rate_type: 0
queue_mode: 0, queue_limit: 0, num_queues: 36
Queue specifics:
Index 0 (Queue ID:0x2, Name: MulticastLeafHigh)
Software Control Info:
(cache) queue id: 0x00000002, wred: 0x88b00000, qlimit (packets): 2048
parent_sid: 0x208, debug_name: MulticastLeafHigh
sw_flags: 0x00010001, sw_state: 0x00000001
orig_min : 0 , min: 0
orig_max : 0 , max: 0
share : 0
Statistics:
tail drops (bytes): 0 , (packets): 0
total enqs (bytes): 0 , (packets): 0
queue_depth (packets): 0
RP計數器
RP處理以下型別的流量：
-
通過路由處理器上千兆乙太網管理埠的管理流量。
-
將系統中的流量（通過ESP）傳送，其中包括在任何SPA上接收的所有控制平面流量。
-
舊協定流量、DECnet、Internet資料包交換(IPX)等。
圖7 RP框圖
這是Cisco ASR 1000系列路由器的點選/插入路徑：
QFP<==>RP Kernel<==>LSMPI<==>Fast-Path Thread<==>Cisco IOS Thread
圖8 Linux共用記憶體點介面(LSMPI)的位置
要顯示RP互連ASIC上ESP互連ASIC的rx計數器，請使用以下命令：
Router#show platform hardware slot r0 serdes statistics From Slot F0 Pkts High: 57 Low: 421540 Bad: 0 Dropped: 0 Bytes High: 5472 Low: 645799280 Bad: 0 Dropped: 0 Pkts Looped: 0 Error: 0 Bytes Looped 0 Qstat count: 0 Flow ctrl count: 196207
若要顯示路由器上Linux共用記憶體輸入介面(LSMPI)的統計資訊，請使用以下命令。LSMPI提供了一種在網路和IOSd之間實現資料包零複製傳輸的方法，以實現高效能。為了達到此目的，在Linux核心中將LSMPI模組與IOSd之間的虛擬記憶體區域共用（記憶體對映）。
Router#show platform software infrastructure lsmpi
LSMPI interface internal stats:
enabled=0, disabled=0, throttled=0, unthrottled=0, state is ready
Input Buffers = 8772684
Output Buffers = 206519
rxdone count = 8772684
txdone count = 206515
案例研究
SPA上的封包捨棄
錯誤資料包
如果封包出現錯誤，則在SPA上捨棄這些封包。這是常見行為，不僅在Cisco ASR 1000系列路由器上，而且在所有平台上。
Router#show interfaces TenGigabitEthernet 1/0/0
TenGigabitEthernet1/0/0 is up, line protocol is up
Hardware is SPA-1X10GE-L-V2, address is 0022.5516.2040 (bia 0022.5516.2040)
Internet address is 192.168.1.1/24
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec,
reliability 250/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Full Duplex, 10000Mbps, link type is force-up, media type is 10GBase-LR
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:45:13, output 00:00:08, output hang never
Last clearing of "show interface" counters 00:00:26
Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
419050 input errors, 419050 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
1 packets output, 402 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 pause output
0 output buffer failures, 0 output buffers swapped out
SIP上的資料包丟棄
QFP的高利用率
在QFP使用率較高的情況下，QFP的背壓會使SIP上的每個介面隊列中的資料包被丟棄。在這種情況下，也會從介面傳送暫停訊框。
Router#show platform hardware port 1/0/0 plim statistics
Interface 1/0/0
RX Low Priority
RX Drop Pkts 21344279 Bytes 1515446578
RX Err Pkts 0 Bytes 0
TX Low Priority
TX Drop Pkts 0 Bytes 0
RX High Priority
RX Drop Pkts 0 Bytes 0
RX Err Pkts 0 Bytes 0
TX High Priority
TX Drop Pkts 0 Bytes 0
ESP上的資料包丟棄
超額認購
如果傳送的封包超過介面的線路速率，則封包會在輸出介面遭捨棄。
Router#show interfaces GigabitEthernet 1/1/0
GigabitEthernet1/1/0 is up, line protocol is up
Hardware is SPA-5X1GE-V2, address is 0021.55dc.3f50 (bia 0021.55dc.3f50)
Internet address is 192.168.2.1/24
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 35/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Full Duplex, 1000Mbps, link type is auto, media type is SX
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00
Last input 02:24:23, output 00:00:55, output hang never
Last clearing of "show interface" counters 00:01:04
Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 48783
...
在QFP上，可以將這些丟棄檢查為Taildrop。
Router#show platform hardware qfp active statistics drop | exclude _0_ ---------------------------------------------------------------- Global Drop Stats Octets Packets ---------------------------------------------------------------- TailDrop 72374984 483790
按資料包分段過載
如果封包由於MTU大小而分段，即使輸入介面小於線路速率，也可能會在輸出介面超出線路速率。在這種情況下，封包會在輸出介面遭捨棄。
Router#show interfaces gigabitEthernet 1/1/0
GigabitEthernet1/1/0 is up, line protocol is up
Hardware is SPA-5X1GE-V2, address is 0022.5516.2050 (bia 0022.5516.2050)
Internet address is 192.168.2.1/24
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 25/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Full Duplex, 1000Mbps, link type is auto, media type is SX
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:36:52, output 00:00:12, output hang never
Last clearing of "show interface" counters 00:00:55
Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 272828
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 99998000 bits/sec, 14290 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
4531543 packets output, 4009748196 bytes, 0 underruns
在QFP上，可以將這些丟棄檢查為Taildrop。
Router#show platform hardware qfp active statistics drop | exclude _0_ ---------------------------------------------------------------- Global Drop Stats Octets Packets ---------------------------------------------------------------- TailDrop 109431162 272769
分段資料包的效能限制
在QFP中，全域封包記憶體(GPM)用於重組分段封包。如果在重組大量分段資料包時耗盡GPM，則這些計數器會顯示丟包數。在許多情況下，這是效能限制。
Router#show platform hardware qfp active statistics drop | ex _0_ ---------------------------------------------------------------- Global Drop Stats Octets Packets ---------------------------------------------------------------- ReassNoFragInfo 39280654854 57344096 ReassTimeout 124672 128
轉發到Null0介面
發往Null0介面的資料包在ESP上被丟棄，並且不轉發到RP。在這種情況下，您可能無法使用傳統命令(show interfaces null0)檢查計數器。 檢查ESP計數器，以便知道資料包丟棄的數目。如果同時使用clear和exclude _0_選項，則您只能檢查新的丟棄資料包。
Router#show platform hardware qfp active statistics drop clear | ex _0_ ---------------------------------------------------------------- Global Drop Stats Octets Packets ---------------------------------------------------------------- Ipv4Null0 11286 99
具有HA不支援功能的RP切換
在RP切換的情況下，這些資料包將被丟棄，直到新的活動RP重新程式設計QFP:
-
如果在交換之前新的活動RP沒有與舊的活動RP同步，則所有資料包都會被丟棄。
-
高可用性(HA)不支援功能處理資料包。
Router#show platform hardware qfp active statistics drop | ex _0_ ---------------------------------------------------------------- Global Drop Stats Octets Packets ---------------------------------------------------------------- Ipv4NoAdj 6993660 116561 Ipv4NoRoute 338660188 5644337
傳送資料包
在Cisco ASR 1000系列路由器上，無法由ESP處理的資料包會被傳送到RP。如果有太多的punt資料包，QFP丟棄統計資訊的TailDrop將增加。
Router#show platform hardware qfp active statistics drop | ex _0_ ---------------------------------------------------------------- Global Drop Stats Octets Packets ---------------------------------------------------------------- TailDrop 26257792 17552
檢查Buffering、Queuing and Scheduling(BQS)隊列輸出計數器以指定丟棄的介面。「internal0/0/rp:0」顯示從ESP到RP要傳送的介面。
Router#show platform hardware qfp active infrastructure bqs queue output default all
Interface: internal0/0/rp:0, QFP if_h: 1, Num Queues/Schedules: 2
Queue specifics:
Index 0 (Queue ID:0x2f, Name: )
Software Control Info:
(cache) queue id: 0x0000002f, wred: 0x88b002d2, qlimit (bytes): 6250048
parent_sid: 0x232, debug_name:
sw_flags: 0x00000011, sw_state: 0x00000001
orig_min : 0 , min: 0
orig_max : 0 , max: 0
share : 1
Statistics:
tail drops (bytes): 26257792 , (packets): 17552
total enqs (bytes): 4433777480 , (packets): 2963755
queue_depth (bytes): 0
Queue specifics:
...
在這種情況下，輸入佇列捨棄會在輸入介面上計數。
Router#show interfaces TenGigabitEthernet 1/0/0
TenGigabitEthernet1/0/0 is up, line protocol is up
Hardware is SPA-1X10GE-L-V2, address is 0022.5516.2040 (bia 0022.5516.2040)
Internet address is 192.168.1.1/24
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Full Duplex, 10000Mbps, link type is force-up, media type is 10GBase-LR
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:15:10, output 00:00:30, output hang never
Last clearing of "show interface" counters 00:14:28
Input queue: 0/375/2438309/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 70886000 bits/sec, 5915 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
2981307 packets input, 4460035272 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
15 packets output, 5705 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 pause output
0 output buffer failures, 0 output buffers swapped out
此命令可以顯示點票的原因：
Router#show platform hardware qfp active infrastructure punt statistics type per-cause
Global Per Cause Statistics
Number of punt causes = 46
Per Punt Cause Statistics
Packets Packets
Counter ID Punt Cause Name Received Transmitted
------------------------------------------------------------------------
00 RESERVED 0 0
01 MPLS_FRAG_REQUIRE 0 0
02 IPV4_OPTIONS 2981307 2963755
...
您還可以檢查該show ip traffic命令。
Router#show ip traffic
IP statistics:
Rcvd: 2981307 total, 15 local destination
0 format errors, 0 checksum errors, 0 bad hop count
0 unknown protocol, 0 not a gateway
0 security failures, 0 bad options, 2981307 with options
Opts: 2981307 end, 0 nop, 0 basic security, 0 loose source route
0 timestamp, 0 extended security, 0 record route
0 stream ID, 2981307 strict source route, 0 alert, 0 cipso, 0 ump
0 other, 0 ignored
Frags: 0 reassembled, 0 timeouts, 0 couldn't reassemble
0 fragmented, 0 fragments, 0 couldn't fragment
Bcast: 0 received, 0 sent
Mcast: 0 received, 0 sent
Sent: 23 generated, 525450 forwarded
Drop: 0 encapsulation failed, 0 unresolved, 0 no adjacency
0 no route, 0 unicast RPF, 0 forced drop, 0 unsupported-addr
0 options denied, 0 source IP address zero
...
Punt全域性策略器設定的Punt限制
如果太多的punt資料包發往路由器本身，則QFP丟棄計數器會使用PuntGlobalPolicerDrops進行Taildrop計數。Punt Global Policer可保護RP免受過載的影響。傳送封包而不是FOR_US封包可以看到這些捨棄。
Router#show platform hardware qfp active statistics drop | ex _0_ ---------------------------------------------------------------- Global Drop Stats Octets Packets ---------------------------------------------------------------- PuntGlobalPolicerDrops 155856 102 TailDrop 4141792688 2768579 ...
此命令可以知道點票的原因：
Router#show platform hardware qfp active infrastructure punt statistics type per-cause
Global Per Cause Statistics
Number of punt causes = 46
Per Punt Cause Statistics
Packets Packets
Counter ID Punt Cause Name Received Transmitted
------------------------------------------------------------------------
00 RESERVED 0 0
01 MPLS_FRAG_REQUIRE 0 0
02 IPV4_OPTIONS 0 0
03 L2 control/legacy 0 0
04 PPP_CONTROL 0 0
05 CLNS_CONTROL 0 0
06 HDLC_KEEPALIVE 0 0
07 ARP 3 3
08 REVERSE_ARP 0 0
09 LMI_CONTROL 0 0
10 incomplete adjacency punt 0 0
11 FOR_US 5197865 2428755
RP上的資料包丟棄
LSMPI上的資料包錯誤
在Cisco ASR 1000系列路由器上，資料包通過Linux共用記憶體突發介面(LSMPI)從ESP傳送到RP。LSMPI是通過Linux共用內存在RP上的IOSd和Linux核心之間傳輸資料包的虛擬介面。從ESP傳送到RP的資料包由RP的Linux核心接收。Linux核心通過LSMPI將這些資料包傳送到IOSD進程。如果您在LSMPI上看到錯誤計數器，則這是軟體缺陷。建立TAC案例。
Router#show platform software infrastructure lsmpi
Lsmpi0 is up, line protocol is up
Hardware is LSMPI
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Unknown, Unknown, media type is unknown media type
output flow-control is unsupported, input flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/1500/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
15643 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
1 input errors, 0 CRC, 3 frame, 0 overrun, 0 ignored, 0 abort
0 watchdog, 0 multicast, 0 pause input
295 packets output, 120491 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
相關資訊
修訂記錄
| 修訂 | 發佈日期 | 意見 |
|---|---|---|
3.0 |
07-Nov-2024 |
重新認證 |
1.0 |
06-Jul-2009 |
初始版本 |
意見