Class: SNMP::Manager

Inherits:
Object
  • Object
show all
Defined in:
rlib/snmp_override.rb

Overview

Manager class from snmplib

Class Method Summary (collapse)

Instance Method Summary (collapse)

Class Method Details

+ (Object) snmp_walk(hostname, community, ifTable_columns)

Run an SNMP query to retrieve the OID or OIDS passed in.

Parameters:

  • hostname (String) —

    host we are querying

  • community (String) —

    SNMP password

  • ifTable_columns (String, Array<String>) —

    The OIDS we want to retrieve from this switch.



42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
 
# File 'rlib/snmp_override.rb', line 42

def self.snmp_walk(hostname, community, ifTable_columns)
  begin
    SNMP::Manager.open(:Host => hostname, :Community => "#{community}", :Version => :SNMPv1) do |manager|
      manager.walk(ifTable_columns) do |row|
        row.each do |vb| 
            oid = vb.name.to_s.split('.')
            yield [oid, vb.value.to_s]
        end
      end
    end
  rescue SignalException => message #We might get an OS level signal. If so, we need to stop
    $stderr.print "#{Signal} #{message}\n"
    exit -1
  rescue Exception => message #Should be a more refined Exception list!
    $stderr.print "(#{hostname}, #{community}, #{ifTable_columns}) Error: #{@name}: #{message}\n"
  end
end

Instance Method Details

- (Object) walk(object_list, index_column = 0)

Overrides walk in the standard SNMP snmp.rb library. Walks a list of ObjectId or VarBind objects using get_next until the response to the first OID in the list reaches the end of its MIB subtree.

Parameters:

  • object_list (Array) —

    List of oids we are looking up

  • index_column (defaults to: 0) —

    The index_column identifies the column that will provide the index for each row. This information is used to deal with “holes” in a table (when a row is missing a varbind for one column).

    A missing varbind is replaced with a varbind with the value NoSuchInstance.
This could be used to instead of this override function, which is a more brute force approach.

Raises:

  • (ArgumentError) 


14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
 
# File 'rlib/snmp_override.rb', line 14

def walk(object_list, index_column=0)
  raise ArgumentError, "expected a block to be given" unless block_given?
  vb_list = @mib.varbind_list(object_list, :NullValue)
  raise ArgumentError, "index_column is past end of varbind list" if index_column >= vb_list.length
  is_single_vb = object_list.respond_to?(:to_str) || object_list.respond_to?(:to_varbind)
  start_list = vb_list
  start_oid = vb_list[index_column].name
  last_oid = start_oid
  loop do
    vb_list = get_next(vb_list).vb_list
    index_vb = vb_list[index_column]
    break if EndOfMibView == index_vb.value
    stop_oid = index_vb.name
    break unless stop_oid.subtree_of?(start_oid)
    last_oid = stop_oid
    if is_single_vb
      yield index_vb
    else
      vb_list = validate_row(vb_list, start_list, index_column)
      yield vb_list
    end
  end
end