The following command displays the contents of a single link state advertisement contained in the OSPF database:
DISPLAY TCPIP,<tcpipjobname>,OMPROUTE,OSPF,LSA,LSTYPE=ls-type, LSID=lsid,ORIG=ad-router,AREAID=area-id
For a summary of all the advertisements in the OSPF database, use the following command:
DISPLAY TCPIP,<tcpipjobname>,OMPROUTE,OSPF,DATABASE,
AREAID=<area-id>
A link state advertisement is defined by its link state type, link state ID and its advertising router. There is a separate link state database for each OSPF area. Providing an area-ID on the command line tells the software which database you want to search. The different kinds of advertisements depend on the value given for link-state-type and are as follows:
Router links: (link-state-type = 1) |
Describe the collected states of a router's interfaces |
Network links: (link-state-type = 2) |
Describe the set of routers attached to a network |
IP Network:
(link-state-type = 3) |
Describe inter-area routes to networks |
ASBR link: (link-state-type = 4) |
Describe inter-area routes to AS boundary routers |
AS external: (link-state-type = 5) |
Describe routes to destinations external to the Autonomous System |
Note: The ORIGINATOR only needs to be specified for link-state-types three, four, and five. The AREAID needs to be specified for all link-state-types except five. Link State IDs, originators (specified by their router IDs), and area IDs take the same format as IP addresses. For example, the backbone area can be entered as 0.0.0.0.
EZZ7880I LSA DETAILS 220
LS AGE: 292
LS OPTIONS: E,DC
LS TYPE: 1
LS DESTINATION (ID): 9.167.100.13
LS ORIGINATOR: 9.167.100.13
LS SEQUENCE NO: 0X80000009
LS CHECKSUM: 0X8F78
LS LENGTH: 36
ROUTER TYPE: ABR
# ROUTER IFCS: 1
LINK ID: 9.67.100.8
LINK DATA: 9.167.100.13
INTERFACE TYPE: 4
NO. OF METRICS: 0
TOS 0 METRIC: 2 (2)
LS AGE |
Indicates the age of the advertisement in seconds. |
LS OPTIONS |
Indicates the optional OSPF capabilities supported by the piece of the routing domain described by the advertisement. These capabilities are denoted by E (processes type 5 externals; when this is not set, the area to which the advertisement belongs has been configured as a stub), T (can route based on TOS), MC (can forward IP multicast datagrams), and DC (can support demand circuits). |
LS TYPE |
Classifies the advertisement and dictates its contents: 1 (router links advertisement), 2 (network link advertisement), 3 (summary link advertisement), 4 (summary ASBR advertisement), 5 (AS external link). |
LS DESTINATION |
Identifies what is being described by the advertisement, dependant on the advertisement type: for router links and ASBR summaries, it is the OSPF router ID; for network links, it is the IP address of the network designated router; for summary links and AS external links, it is a network/subnet number. |
LS ORIGINATOR |
OSPF router ID of the originating router. |
LS SEQUENCE NUMBER |
Used to distinguish separate instances of the same advertisement. Should be looked at as a signed 32-bit integer. Starts at 0x80000001, and increments by one each time the advertisement is updated. |
LS CHECKSUM |
A checksum of advertisement contents, used to detect data corruption. |
LS LENGTH |
The size of the advertisement in bytes. |
ROUTER TYPE |
Indicates the level of function of the advertising router. ASBR means that the router is an AS boundary router, ABR that the router is an area border router, and W that the router is a wildcard multicast receiver. |
# ROUTER IFCS |
The number of router interfaces described in the advertisement. |
LINK ID |
Indicates what the interface connects to. Depends on Interface type. For interfaces to routers (that is, point-to-point links), the Link ID is the neighbor's router ID. For interfaces to transit networks, it is the IP address of the network designated router. For interfaces to stub networks, it is the network's network/subnet number. |
LINK DATA |
Four bytes of extra information concerning the link, it is either the IP address of the interface (for interfaces to point-to-point networks and transit networks), or the subnet mask (for interfaces to stub networks). |
INTERFACE TYPE |
One of the following: 1 (point-to-point connection to another router), 2 (connection to transit network), 3 (connection to stub network), or 4 (virtual link). |
NO. OF METRICS |
The number of nonzero TOS values for which metrics are provided for this interface. For the OS/390 implementation, this value is always zero. |
TOS 0 METRIC |
The cost of the interface. |
The LS age, LS options, LS type, LS destination, LS originator, LS sequence no, LS checksum, and LS length fields are common to all advertisements. The Router type and # router ifcs are seen only in router links advertisements. Each link in the router advertisement is described by the Link ID, Link Data, and Interface type fields.
See also: