網絡流量分析利器-可視化網絡-netflow【3】-netflow版本5和版本9區別

網絡流量分析利器-可視化網絡-netflow【1】-基礎原理
網絡流量分析利器-可視化網絡-netflow【2】-Cisco NetFlow 工作原理介紹及配置
網絡流量分析利器-可視化網絡-netflow【3】-netflow版本5和版本9區別
網絡流量分析利器-可視化網絡-netflow【4】-接收器nfdump簡介
網絡流量分析利器-可視化網絡-netflow【5】-linux下數據採集器fprobe
網絡流量分析利器-可視化網絡-netflow【6】-生產網流量監控架構設計
fprobe參數 -e
fprobe參數 -n -k

注:數據來源於思科官網
Version 5 :
https://www.cisco.com/c/en/us/td/docs/net_mgmt/netflow_collection_engine/3-6/user/guide/format.html#wp1006108
Version 9 :
https://www.cisco.com/en/US/technologies/tk648/tk362/technologies_white_paper09186a00800a3db9.html

以下爲重點摘要,如格式存在問題,請直接瀏覽官網

Version 5

Version 5 Header Format

Bytes Contents Description
0-1 version NetFlow export format version number
2-3 count Number of flows exported in this packet (1-30)
4-7 SysUptime Current time in milliseconds since the export device booted
8-11 unix_secs Current count of seconds since 0000 UTC 1970
12-15 unix_nsecs Residual nanoseconds since 0000 UTC 1970
16-19 flow_sequence Sequence counter of total flows seen
20 engine_type Type of flow-switching engine
21 engine_id Slot number of the flow-switching engine
22-23 sampling_interval First two bits hold the sampling mode; remaining 14 bits hold value of sampling interval

Version 5 Flow Record Format

Bytes Contents Description
0-3 srcaddr Source IP address
4-7 dstaddr Destination IP address
8-11 nexthop IP address of next hop router
12-13 input SNMP index of input interface
14-15 output SNMP index of output interface
16-19 dPkts Packets in the flow
20-23 dOctets Total number of Layer 3 bytes in the packets of the flow
24-27 First SysUptime at start of flow
28-31 Last SysUptime at the time the last packet of the flow was received
32-33 srcport TCP/UDP source port number or equivalent
34-35 dstport TCP/UDP destination port number or equivalent
36 pad1 Unused (zero) bytes
37 tcp_flags Cumulative OR of TCP flags
38 prot IP protocol type (for example, TCP = 6; UDP = 17)
39 tos IP type of service (ToS)
40-41 src_as Autonomous system number of the source, either origin or peer
42-43 dst_as Autonomous system number of the destination, either origin or peer
44 src_mask Source address prefix mask bits
45 dst_mask Destination address prefix mask bits
46-47 pad2 Unused (zero) bytes

Version 9

Version 9 Header Format

Field Name Value
Version The version of NetFlow records exported in this packet; for Version 9, this value is 0x0009
Count Number of FlowSet records (both template and data) contained within this packet
System Uptime Time in milliseconds since this device was first booted
UNIX Seconds Seconds since 0000 Coordinated Universal Time (UTC) 1970
Sequence Number Incremental sequence counter of all export packets sent by this export device; this value is cumulative, and it can be used to identify whether any export packets have been missedNote: This is a change from the NetFlow Version 5 and Version 8 headers, where this number represented "total flows."
Source ID The Source ID field is a 32-bit value that is used to guarantee uniqueness for all flows exported from a particular device. (The Source ID field is the equivalent of the engine type and engine ID fields found in the NetFlow Version 5 and Version 8 headers). The format of this field is vendor specific. In the Cisco implementation, the first two bytes are reserved for future expansion, and will always be zero. Byte 3 provides uniqueness with respect to the routing engine on the exporting device. Byte 4 provides uniqueness with respect to the particular line card or Versatile Interface Processor on the exporting device. Collector devices should use the combination of the source IP address plus the Source ID field to associate an incoming NetFlow export packet with a unique instance of NetFlow on a particular device.

Version 9 Template FlowSet Field Descriptions

Field Name Value
FlowSet ID The FlowSet ID is used to distinguish template records from data records. A template record always has a FlowSet ID in the range of 0-255. Currently, the template record that describes flow fields has a FlowSet ID of zero and the template record that describes option fields (described below) has a FlowSet ID of 1. A data record always has a nonzero FlowSet ID greater than 255.
Length Length refers to the total length of this FlowSet. Because an individual template FlowSet may contain multiple template IDs (as illustrated above), the length value should be used to determine the position of the next FlowSet record, which could be either a template or a data FlowSet.Length is expressed in Type/Length/Value (TLV) format, meaning that the value includes the bytes used for the FlowSet ID and the length bytes themselves, as well as the combined lengths of all template records included in this FlowSet.
Template ID As a router generates different template FlowSets to match the type of NetFlow data it will be exporting, each template is given a unique ID. This uniqueness is local to the router that generated the template ID.Templates that define data record formats begin numbering at 256 since 0-255 are reserved for FlowSet IDs.
Field Count This field gives the number of fields in this template record. Because a template FlowSet may contain multiple template records, this field allows the parser to determine the end of the current template record and the start of the next.
Field Type This numeric value represents the type of the field. The possible values of the field type are vendor specific. Cisco supplied values are consistent across all platforms that support NetFlow Version 9.At the time of the initial release of the NetFlow Version 9 code (and after any subsequent changes that could add new field-type definitions), Cisco provides a file that defines the known field types and their lengths.The currently defined field types are detailed in Table 6.
Field Length This number gives the length of the above-defined field, in bytes.
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