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    <p>It sounds like you're on the right track. In order to define a table as a child of another table, you simply index it by the parent's index plus the child's index (e.g., <code>0.1.8.23.7.2.42</code> where <code>2</code> is the parent index and <code>42</code> is the child index).</p> <p>For example, you could define a parent like:</p> <pre><code>parentTable OBJECT-TYPE SYNTAX SEQUENCE OF parentEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Parent table" ::= { example 1 } parentEntry OBJECT-TYPE SYNTAX ParentEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entry in Parent table" INDEX { parentIndex } ::= { parentTable 1 } ParentEntry ::= SEQUENCE { parentIndex Unsigned32, -- other columns in the table } -- define the columns in the parent table </code></pre> <p>With a child table defined as:</p> <pre><code>childTable OBJECT-TYPE SYNTAX SEQUENCE OF childEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Child table" ::= { example 2 } childEntry OBJECT-TYPE SYNTAX ChildEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entry in Child table" INDEX { parentIndex, childIndex } ::= { childTable 1 } ChildEntry ::= SEQUENCE { childIndex Unsigned32, -- other columns in the table } -- define the columns in the child table </code></pre> <p>Note that it's not necessary to list parentIndex in the ChildEntry sequence since it's already be declared elsewhere in the MIB.</p> <p>This method works well and it even responds to snmp walks without issue.</p> <p>Once you have a MIB that you think accurately defines the structure you want, you can validate it using <a href="http://www.ibr.cs.tu-bs.de/projects/libsmi/smilint.html" rel="noreferrer"><code>smilint</code></a> if you are on a linux machine or have cygwin installed or you can <a href="http://www.ibr.cs.tu-bs.de/projects/libsmi/tools/" rel="noreferrer">validate it online</a>.</p> <p><strong>Update</strong></p> <p>This pattern will work for deeper nesting as well.</p> <p>A grandchild table could be defined as:</p> <pre><code>grandChildTable OBJECT-TYPE SYNTAX SEQUENCE OF grandChildEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Grandchild table" ::= { example 3 } grandChildEntry OBJECT-TYPE SYNTAX GrandChildEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entry in Grandchild table" INDEX { parentIndex, childIndex, grandChildIndex } ::= { grandChildTable 1 } grandChildEntry ::= SEQUENCE { grandChildIndex Unsigned32, -- other columns in the table } -- define the columns in the grandChild table </code></pre> <p>The only limit on nesting depth is the maximum OID length (which, I believe, is 127): A column's base OID length plus the number of indices for the table must be less than the maximum OID length.</p> <p>One other item to note is that at each level there can be multiple siblings.</p> <p>A second child could be defined as:</p> <pre><code>secondchildTable OBJECT-TYPE SYNTAX SEQUENCE OF secondchildEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Second child table" ::= { example 4 } secondchildEntry OBJECT-TYPE SYNTAX SecondchildEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entry in Second child table" INDEX { parentIndex, secondchildIndex } ::= { secondchildTable 1 } SecondchildEntry ::= SEQUENCE { secondchildIndex Unsigned32, -- other columns in the table } -- define the columns in the second child table </code></pre>
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    1. POSNMP: ASN.1 MIB Definitions. Referencing a table within a table
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    1. COVery good. Thanks for the quick feedback.
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    2. COwould the principle apply for a third table, i.e. it would have 3 indices, or are there better ways to manage it as the depth of the hierarchy grows?
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    3. CO@TheJuice: Yes, the principle applies to children tables up to the maximum OID length deep (which I believe is 127). As you guessed, each additional level would have another index. I'll edit my answer to include an example. I am not aware of any better ways to manage deeper hierarchies.
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