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Configuration Guide - Network Management and Monitoring

CloudEngine 8800, 7800, 6800, and 5800 V200R005C10

This document describes the configurations of Network Management and Monitoring, including SNMP, RMON, NETCONF, OpenFlow, LLDP, NQA, Mirroring, Packet Capture, Packet Trace, Path and Connectivity Detection Configuration, NetStream, sFlow, and iPCA.
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Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Understanding IOAM

Understanding IOAM

As shown in Figure 17-1, the IOAM system, the IOAM system consists of the following parts:

Figure 17-1 Network diagram of the IOAM system
  • Ingress node: Collects and copies service packets, adds OAM information to the copied packets, and then forwards the packets.
  • Transit node: Forwards IOAM packets and adds OAM information about the local hop to the packets.
  • Egress node: Sends the received IOAM packets to the analyzer for analysis.
  • Analyzer: Collects IOAM packets and analyzes the network status based on the OAM information carried in the packets.
NOTE:

When the outbound interface of the route from the egress node to the analyzer is a Layer 3 sub-interface, IOAM packets cannot be sent to the analyzer.

After collecting and copying service packets, the ingress node sends the packets to the analyzer through one or more transit nodes and the egress node. When a packet passes through each hop, OAM information about the hop is added to the packet.

Currently, IOAM can be used to copy TCP, UDP, and VXLAN packets and add OAM information. Figure 17-2 shows the IOAM packet format.
Figure 17-2 IOAM packet format
NOTE:

If the CE8850-64CQ-EI functions as a transit node, it adds timestamp (TS) information to the tail of a packet, instead of adding metadata (MD) information after the OAM header (OAM HDR). The egress node converts the TS information at the tail of the packet into the MD format.

Here, a UDP/TCP packet is used as an example. Figure 17-3 shows the format of an IOAM packet when the CE8850-64CQ-EI functions as a transit node.

Figure 17-3 IOAM packet format (the CE8850-64CQ-EI functions as a transit node)

The OAM HDR is the header of an IOAM packet, and the MD is the data added for each hop. Figure 17-4 and Figure 17-5 show the formats of the OAM HDR and MD in an IOAM packet, respectively.

Figure 17-4 Format of the OAM HDR
Table 17-1 Description of fields in the OAM HDR

Field

Length

Description

Header

64 bits

Header ID.

Version

8 bits

Version number. The value is 0x01.

Message Type

8 bits

Information type. The value is 0x01.

Flags

16 bits

Flag bit.

Telemetry Request Vector

32 bits

MD ID. The value is 0xFFFFFFFF.

Hop Limit

8 bits

Maximum number of hops that a packet can pass through. The value is 8.

Hop Count

8 bits

Number of hops that a packet has passed through.

Maximum Length

16 bits

Maximum MD length. The value is 256 bytes.

Current Length

16 bits

Current MD length, in bytes.

Sender's Handle

16 bits

ID set by the sender.

Sequence Number

16 bits

Packet sequence number.

Figure 17-5 Format of the MD
Table 17-2 Description of fields in the MD

Field

Length

Description

Device ID

32 bits

Node ID.

Template ID

3 bits

Packet template ID.

Congestion

5 bits

Packet congestion flag. Currently, this field is not supported.

Egress Port Drop Pkt Byte Cnt Upper

8 bits

This field is used with Egress Port Drop Pkt Byte Cnt to indicate the number of discarded packets on the outbound interface. Currently, this field is not supported.

IP_TTL

8 bits

TTL value of a packet.

Queue_id

8 bits

Queue ID.

Rx Timestamp Seconds Upper

32 bits

Timestamp when a packet is received, in seconds.

Rx Timestamp Seconds

16 bits

Rx Timestamp Nano-Seconds Upper

16 bits

Timestamp when a packet is received, in nanoseconds.

Rx Timestamp Nano-Seconds

16 bits

Tx Timestamp Nano-Seconds Upper

16 bits

Timestamp when a packet is sent, in nanoseconds.

Tx Timestamp Nano-Seconds

16 bits

Egress Port Utilization [%]

16 bits

Bandwidth usage of the outbound interface.

Ingress Port [module, port]

16 bits

Inbound interface of a packet, including the chip ID and interface number.

Egress Port [module, port]

16 bits

Outbound interface of a packet, including the chip ID and interface number.

Egress Port Drop Pkt Byte Cnt

32 bits

This field is used with Egress Port Drop Pkt Byte Cnt Upper to indicate the number of discarded packets on the outbound interface. Currently, this field is not supported.

The TS information is OAM information added to the tail of a packet. Each TS contains an ingress timestamp and an egress timestamp. Figure 17-6 shows the format of an ingress or egress timestamp in the TS.
Figure 17-6 Format of an ingress or egress timestamp
Table 17-3 Description of fields in an ingress or egress timestamp

Field

Length

Description

Time

48 bits

Timestamp when a packet is received or sent.

Reserved

8 bits

Reserved field.

Origin ID

23 bits

Source ID. After the TS is converted into the MD format, this field is mapped to Device ID and Ingress Port/Egress Port.

NOTE:

For the CE8850-64CQ-EI, when the TS is added to the tail of a packet, Device ID and Ingress Port/Egress Port cannot be added. Therefore, after the TS is converted into the MD format, Device ID and Ingress Port/Egress Port have random values. As a result, the analysis system cannot accurately determine the path of packets.

X

1 bit

Flag indicating whether a packet is an ingress or egress packet. The value 0 indicates an ingress packet and 1 indicates an egress packet.

FCS/unused

32 bits

Frame check sequence.

Translation
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Updated: 2019-04-20

Document ID: EDOC1100075365

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