3com 2928 Guida Utente

 

1-3 

A subtree OID used with a subtree mask defines a view subtree. A subtree mask is in hexadecimal 
format. After it is converted to binary bits, each bit corresponds to a node of the OID.  

z

 

1 means precise matching, that is, the OID of the MIB object to be accessed must be identical with 
the subtree OID.  

z

 

0 means wildcard matching, that is, the OID of the MIB object to be accessed can be different from 
the subtree OID.  

For example, provided the subtree mask 0xDB (11011011 in binary) and the subtree OID 1.3.6.1.6.1.2.1, 
their relationship is as shown in 

. The view determined by them includes all the nodes under 

the subtree whose OID is 1.3.*.1.6.*.2.1, where * represents any number. 

Subtree OID and subtree mask 

 

 

z

 

If the number of bits in the subtree mask is greater than the number of nodes of the OID, the 
excessive bits of the subtree mask will be ignored during subtree mask-OID matching. 

z

 

If the number of bits in the subtree mask is smaller than the number of nodes of the OID, the short 
bits of the subtree mask will be set to 1 during subtree mask-OID matching. 

z

 

If no subtree mask is specified, the default subtree mask (all Fs) will be used for mask-OID 
matching. 

 

As configurations for SNMPv3 differ substantially from those for SNMPv1 and SNMPv2c, their 
configuration tasks are introduced separately as follows. 

Perform the tasks in 

 to configure SNMPv1 or SNMPv2c: 

SNMPv1 or SNMPv2c configuration task list 

Required 
The SNMP agent function is disabled by default. 

Configuring an SNMP View 

Optional 
After creating SNMP views, you can specify an SNMP view 

for an SNMP community to limit the MIB objects that can be 

accessed by the SNMP community.