SNMP学习笔记之SNMP树形结构介绍

SNMP VEQSIONS VEQSION 1 VEQSION 2 VEQSION 3 SNMP VI - The Least Secure version of SNMP Protocol due to its lack of encryption. sending passwords over Plain Text SNMP v2 - Large improvements in over the first version, including transport mappings, MIB Structure elements and most importantly, improved authentication and security updates. SNMP v3 - Implemented "User-Based Security". This security feature allows you to set Authentication/Encryption based on the user requirements. The 3 levels of auth. are: NoAuthNoPriv, AuthNoPriv and Authpriv.

Basic command of SNMP:

• GET: The GET operation is a request sent by the manager to the managed device. It is performed to retrieve one or more values from the managed device.
• GET NEXT: This operation is similar to the GET. The significant difference is that the GET NEXT operation retrieves the value of the next OID in the MIB tree.
• GET BULK: The GETBULK operation is used to retrieve voluminous data from large MIB table.
• SET: This operation is used by the managers to modify or assign the value of the Managed device.
• TRAPS: Unlike the above commands which are initiated from the SNMP Manager, TRAPS are initiated by the Agents. It is a signal to the SNMP Manager by the Agent on the occurrence of an event.
• INFORM: This command is similar to the TRAP initiated by the Agent, additionally INFORM includes confirmation from the SNMP manager on receiving the message.
• RESPONSE: It is the command used to carry back the value(s) or signal of actions directed by the SNMP Manager.

cclTT(01 DIRECTORY (1) wa.2(1) SYSTEM MIB Tree Diagram MIB The Registered Tree Root MEMBER BODY AUTHORITY AUSTRALIA EXPERIMENTAL PRIVATE JOINT Iso.cclTr12? ORGANIZATION (3) DOD INTERNET SNMP

(2) org (3) dod (6) Internet (l ) experime directory (I) rWb-2 (1) interfaces (2) private (4) enterprise (1) microsoft systn (I) ip (4) Cisco (9) (311) juniperMIB (2636 OID Tree Example

• 1.3.6.1.2.1.1 - SNMP MIB-2 System
• 1.3.6.1.2.1.2 - SNMP MIB-2 Interfaces
• 1.3.6.1.2.1.3 - at
• 1.3.6.1.2.1.4 - ip
• 1.3.6.1.2.1.5 - icmp
• 1.3.6.1.2.1.6 - tcp
• 1.3.6.1.2.1.7 - udp
• 1.3.6.1.2.1.8 - egp
• 1.3.6.1.2.1.9 - cmot
• 1.3.6.1.2.1.10 - transmission
• 1.3.6.1.2.1.11 - snmp
• 1.3.6.1.2.1.14 - OSPF Version 2 MIB
• 1.3.6.1.2.1.15 - BGPv4
• 1.3.6.1.2.1.16 - Managed Objects for Bridges
• 1.3.6.1.2.1.17 - Bridge Mib
• 1.3.6.1.2.1.22 - rptrHealth
• 1.3.6.1.2.1.25 - HOST-RESOURCES-MIB, from RFC 1514
• 1.3.6.1.2.1.26 - Ethernet MAU mib
• 1.3.6.1.2.1.27 - Application MIB module
• 1.3.6.1.2.1.28 - MTA MIB module
• 1.3.6.1.2.1.29 - X.500 Directory MIB module
• 1.3.6.1.2.1.31 - ifMib
• 1.3.6.1.2.1.33 - upsMIB
• 1.3.6.1.2.1.34 - snaNode
• 1.3.6.1.2.1.38 - mdmMib
• 1.3.6.1.2.1.41 - sdlcStatus
• 1.3.6.1.2.1.43 - Printer-MIB
• 1.3.6.1.2.1.47 - entity-mib
• 1.3.6.1.2.1.69 - docsDev
• 1.3.6.1.2.1.92 - notificationLogMIB

OID:

This is a sample structure of OD:

Iso(1).org(3).dod(6).internet(1).private(4).transition(868).products(2).chassis(4).card(1).slotCps(2)-cpsSlotSummary(1).cpsModuleTable(1).cpsModuleEntry(1).cpsModuleModel(3).3562.3

or just:

1.3.6.1.4.868.2.4.1.2.1.1.1.3.3562.3

Private OID:

Many manufactures can supply custom MIB files for their hardware ,such as temperature , fan speed.

The MIB file is hard to read, they are only meant to be imported, or "compiled " by a Management Station.

Below is an example of Cisco MIB file for environment monitoring.

计算机生成了可选文字: S 2 iOOCISCOEnVMonVO ItagestatusEntry 0 日 ] ECT —TY P E 囗 SYNTAX M × 一 C 匚 E 5 5 not—accessibleO STAT 凵 5 C 凵 r r e nt 囗 凵 苁 n entry n the voltage S t at 凵 S D E 5 匚 R I PT 10 N 囗 t 彐 匕 ] e ， representing the S t at 凵 S 囗 Of the associated testpoint maintained 匕 the environmentalO { CiSCOEnVMonV01tageStatuSIndex } 囗 m 囗 n ] t 囗 r 。 I N D EX { CiSCOEnVMonV01tageStatuSTab1e 1 } 囗 囗 SEQUENCE { 囗 Integer32 （ 0 ． ． 214 74 8 54 7 〕 ， 囗 Displ aystring ， 囗 dl_OW I e g e r 2 ， 囗 ciscoEnVMonVOltageThresholdHigh I nt e g e r 2 ， CiSCOEnVMonV01tageLaStShutdown I e g e r 2 ， 囗 CiSCOEnVMonV01tageState 匚 ] S C 囗 E 囗 n St CiSCOEnVMonV01tageStatuSIndex 0 日 ] ECT —TY P E 囗 SYNTAX Integer32 （ 0 ． ． 21474H 547 〕 囗 STAT 凵 5 C 凵 r r e nt 囗 M × 一 C 匚 E 5 5 not—accessibleO D E 5 匚 R I PT 10 N 囗 index for the testpoint being This index S for 5 NM P purposes 囗 n ] ， and has n 囗 囗 ] nt r ] n S ] C m e 彐 n ] n 0 。 凵 囗

Cisco MIB information:

http://snmp.cloudapps.cisco.com/Support/SNMP/do/BrowseMIB.do?local=en&step=2

Load MIB file:

The files below is F5 MIB file.

计算机生成了可选文字: F5 一 8 《 G 《 P ． 监 PM 一 M 《 8 F5-BIGIP-COMMON-MIB F5 ． 8 《 G 《 P ． GLOB 监 L ． M 化 F5-81GIP-LOCAL-M18 F5-81GIP-SYSTEM-M18 2012 / 3 / 28 星 期 2012 / 3 / 28 星 期 2012 / 3 / 28 星 期 2012 / 3 / 28 星 期 ． 2012 / 3 / 28 星 期 交 本 交 栏 交 本 交 栏 交 本 交 栏 交 本 交 栏 交 本 交 栏 105 KB 30 KB 1g5 KB 5 31 KB 401 KB

We can use MIB Browser to load these file ,and you can see the F5 private OID in the picture.

参考