Q-Logic 7.1 Manuale Utente

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2 – SNMP Overview
Management Information Base
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Management Information Base
Management information bases (MIBs) define the properties of the managed 
object within the device to be managed. Every managed device keeps a database 
of values for each definition written in the MIB. It is not the actual database itself; it 
is implementation dependant. Definition of the MIB conforms to the Structure of 
Management Information (SMI) given in Request For Comment (RFC) 1155. The 
latest Internet MIB is given in RFC 1213, and is sometimes called MIB-II. 
User Datagram Protocol
SANbox switches support the following User Datagram Protocol (UDP) settings:
„
Agents “listen” on UDP port 161. 
„
Responses are sent back to the originating Network Management Station 
(NMS) port from a dynamic port, although many agents use port 161 also for 
this target. 
„
The maximum SNMP message size is 65507 octets (maximum UDP 
message size). 
„
The minimum receive packet size for SNMP implementations is 484 octets 
in length. 
„
Agent and Network Monitoring Systems are responsible for determining 
error recovery. 
Table 2-1. Trap Severity Levels
Event Type
Severity Level
Unknown
1
Emergency
2
Alert
3
Critical
4
Error
5
Warning
6
Notify
7
Info
8
Debug
9
Mark
10