MIBDESC.DATA data set

The MIBDESC.DATA data set defines the short names for MIB variables. Short names are the character representation for the ASN.1 variable names. For example, sysUpTime is the short name for 1.3.6.1.2.1.1.3.0 (the MIB variable that stores the time since the SNMP agent was last restarted). Short names are generally shown as a combination of upper and lowercase characters, though SNMP on z/OS® Communications Server ignores these case distinctions. Variable names must always be in ASN.1 language when they are sent to an SNMP agent. You can always use ASN.1 language to specify the variable names in an enterprise-specific tree (assuming that the agent supports them). You can use these short names to specify the MIB variables.

When you issue an SNMP GET, GETNEXT, or SET command, and specify the variable name in ASN.1 notation, the SNMP Query Engine uses that name and sends it in the SNMP packet to the agent. When you issue an SNMP GET, GETNEXT, or SET command, and specify the short name for the variable (for example, sysDescr), the SNMP Query Engine looks for that name in the MIBDESC.DATA data set and uses the ASN.1 name specified in the data set when it sends the SNMP packet to the agent.

The SNMPQE address space must be able to access the MIBDESC.DATA data set.

You can change the short names in the MIBDESC.DATA data set to the equivalent in your national language. You can also leave the current names and add the equivalent names in your national language. However, the SNMP MIBVNAME function returns only the first entry found in the data set that satisfies the search. In addition, all enterprise-specific variables used by hosts in your network should be added to this data set.

Entries in the data set do not need to be in a specific sequence. Each name starts on a new line. The following entry shows the line format.

short_name asn.1_name type time_to_live

Each variable on the line is separated by either one or more spaces or tabs. An asterisk (*) in column 1 indicates that the line is a comment line.

The following sample is a MIBDESC.DATA line with a sysDescr variable translated in Dutch and a few enterprise variables added (in this example, company ABC received 1.3.6.1.4.1.42 as the ASN.1 number for their enterprise):

*-------------------------------------------------------------*
* MIB Variable name | ASN.1 notation        | Type     | TTL  *
*-------------------------------------------------------------*
* Following is Dutch name for sysDescr
systeemBeschrijving  1.3.6.1.2.1.1.1.         display    900
sysDescr             1.3.6.1.2.1.1.1.         display    900
  ...
  other entries
  ...
* Following are Enterprise-Specific variables for company ABC
ABCInfoPhone         1.3.6.1.4.1.42.1.1       display    900
ABCInfoAddress       1.3.6.1.4.1.42.1.2       display    900

The TTL field contains the number of seconds that a variable lives in the Query Engine’s internal cache. If there are multiple requests for the same variable within the TTL period, the variable value is obtained from the cache, and unnecessary network traffic is avoided.

You can define multiple short names or text names for the same variable, as shown with the Dutch translation of the sysDescr variable. In this case, the SNMP Query Engine returns the first value in the table on an SNMP MIBVNAME request. In the previous example, the SNMP Query Engine would return systeemBeschrijving and not sysDescr. The name returned is in mixed case.

When the SNMP Query Engine receives a short name or text name in a GET, GETNEXT, or SET request, it compares the name against the entries in the MIBDESC.DATA data set. This comparison is not case-sensitive. For example, a request for SYSDESCR, SysDescr, or sysDescr matches the sysDescr entry with an ASN.1 notation of 1.3.6.1.2.1.1.1..

When the SNMP Query Engine receives an SNMP response, it looks up the variable in the MIBDESC.DATA table Type field for information about translating the value into displayable characters. The information contained in the Type field is case-sensitive and must be specified in lowercase.

Note: If you are using SNMP to receive response or trap PDUs which contain enterprise-specific variables, the variables must be added to the MIBDESC.DATA data set.