3.12. OSPF External Link State Database (original) (raw)

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3.12. OSPF External Link State Database

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3.12. OSPF External Link State Database

3.12. OSPF External Link State Database

-- OSPF Link State Database, External

-- The Link State Database contains the Link State -- Advertisements from throughout the areas that the -- device is attached to.

-- This table is identical to the OSPF LSDB Table in -- format, but contains only External Link State -- Advertisements. The purpose is to allow external -- LSAs to be displayed once for the router rather -- than once in each non-stub area.

ospfExtLsdbTable OBJECT-TYPE
    SYNTAX   SEQUENCE OF OspfExtLsdbEntry
    MAX-ACCESS   not-accessible
    STATUS   current
    DESCRIPTION
       "The OSPF Process's Links State Database."
   REFERENCE
      "OSPF Version 2, Section 12  Link  State  Adver-
      tisements"
  ::= { ospf 12 }


ospfExtLsdbEntry OBJECT-TYPE
    SYNTAX   OspfExtLsdbEntry
    MAX-ACCESS   not-accessible
    STATUS   current
    DESCRIPTION
       "A single Link State Advertisement."
   INDEX { ospfExtLsdbType, ospfExtLsdbLsid, ospfExtLsdbRouterId }
   ::= { ospfExtLsdbTable 1 }

OspfExtLsdbEntry ::= SEQUENCE { ospfExtLsdbType INTEGER, ospfExtLsdbLsid IpAddress, ospfExtLsdbRouterId RouterID, ospfExtLsdbSequence Integer32, ospfExtLsdbAge Integer32, ospfExtLsdbChecksum Integer32, ospfExtLsdbAdvertisement OCTET STRING }

ospfExtLsdbType OBJECT-TYPE
    SYNTAX   INTEGER    {
                asExternalLink (5)
              }
    MAX-ACCESS   read-only
    STATUS   current
    DESCRIPTION
       "The type  of  the  link  state  advertisement.
       Each  link state type has a separate advertise-
       ment format."
   REFERENCE
      "OSPF Version 2, Appendix A.4.1 The  Link  State
      Advertisement header"
  ::= { ospfExtLsdbEntry 1 }


ospfExtLsdbLsid OBJECT-TYPE
    SYNTAX   IpAddress
    MAX-ACCESS   read-only
    STATUS   current
    DESCRIPTION
       "The Link State ID is an LS Type Specific field
       containing either a Router ID or an IP Address;
       it identifies the piece of the  routing  domain
       that is being described by the advertisement."
   REFERENCE
      "OSPF Version 2, Section 12.1.4 Link State ID"
  ::= { ospfExtLsdbEntry 2 }


ospfExtLsdbRouterId OBJECT-TYPE
    SYNTAX   RouterID
    MAX-ACCESS   read-only
    STATUS   current
    DESCRIPTION
       "The 32 bit number that uniquely identifies the
       originating router in the Autonomous System."
   REFERENCE
      "OSPF Version 2, Appendix C.1 Global parameters"
  ::= { ospfExtLsdbEntry 3 }

-- Note that the OSPF Sequence Number is a 32 bit signed -- integer. It starts with the value '80000001'h, -- or -'7FFFFFFF'h, and increments until '7FFFFFFF'h -- Thus, a typical sequence number will be very negative. ospfExtLsdbSequence OBJECT-TYPE SYNTAX Integer32 MAX-ACCESS read-only STATUS current DESCRIPTION "The sequence number field is a signed 32-bit integer. It is used to detect old and dupli- cate link state advertisements. The space of sequence numbers is linearly ordered. The larger the sequence number the more recent the advertisement." REFERENCE "OSPF Version 2, Section 12.1.6 LS sequence number" ::= { ospfExtLsdbEntry 4 }

ospfExtLsdbAge OBJECT-TYPE
    SYNTAX   Integer32    -- Should be 0..MaxAge
    MAX-ACCESS   read-only
    STATUS   current
    DESCRIPTION
       "This field is the age of the link state adver-
       tisement in seconds."
   REFERENCE
      "OSPF Version 2, Section 12.1.1 LS age"
  ::= { ospfExtLsdbEntry 5 }


ospfExtLsdbChecksum OBJECT-TYPE
    SYNTAX   Integer32
    MAX-ACCESS   read-only
    STATUS   current
    DESCRIPTION
       "This field is the  checksum  of  the  complete
       contents  of  the  advertisement, excepting the
       age field.  The age field is excepted  so  that
       an   advertisement's  age  can  be  incremented
       without updating the  checksum.   The  checksum
       used  is  the same that is used for ISO connec-
       tionless datagrams; it is commonly referred  to
       as the Fletcher checksum."
   REFERENCE
      "OSPF Version 2, Section 12.1.7 LS checksum"
  ::= { ospfExtLsdbEntry 6 }


ospfExtLsdbAdvertisement OBJECT-TYPE
    SYNTAX   OCTET STRING (SIZE(36))
    MAX-ACCESS   read-only
    STATUS   current
    DESCRIPTION
       "The entire Link State Advertisement, including
       its header."
   REFERENCE
      "OSPF Version 2, Section 12  Link  State  Adver-
      tisements"
  ::= { ospfExtLsdbEntry 7 }

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3.12. OSPF External Link State Database