IBM SC30-3865-04 - Manual (Page 266)

Service nodes maintain two tables: a routing table and a neighbor table. Both of
these tables have timers that age their contents to eliminate out-of-date entries.
Routing updates for X.25 interfaces occur when there is a change in the routing
database, for example, when a node goes up/down or the metric changes.
Routing Table
The routing table contains information about the service nodes. Figure 14 shows a
sample routing table. Descriptions of the fields in this table follow the figure.
Routing Table Field
Description
Net Address
The Net Address is a unique 32-bit number. An S, H, or P preceding the
Net Address field indicates the following:
S Indicates the service node is in suspended state and is advertised,
for 90 seconds, as being down. After 90 seconds, the router
removes the entry for this service node from the routing table.
H Indicates the service node is in hold-down state and is advertised,
for 2 minutes, as being down. After 2 minutes, the router advertises
the service node as operational. If a service node is in suspended
state and it receives an RTP packet, the service node enters the
hold-down state.
P Indicates that the X.25 interface enters permanent state for 4-1/2
minutes after initialization. After 4-1/2 minutes, the neighbor enters
the permanent state and its age stays at 0 while in this state. If the
X.25 interface goes down, the entry is removed from the routing
table.
Next Hop Nbr Addr
The address of the neighbor service node that is the next hop on the
least-cost path to the network.
Nbr Intf
The medium to which the next hop neighbor service node is attached.
Metric An estimated cost, in 200-millisecond increments, to route the VINES
packet to the destination service node.
Net Address Next Hop Nbr Addr Nbr Intf Metric Age (secs)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
S 30622222 30622222:0001 Eth/0 20 30
H 0027AA21 0027AA21:0001 Eth/1 2 120
P 0034CC11 0034CC11:0001 X.25/0 45 0
3 Total Routes
S ⇒ Entry is suspended, H ⇒ Entry is in Hold-down,
P
⇒
Entry is permanent
Figure 14. Sample Routing Table
Using VINES
236 MRS V3.2 Protocol Config Ref Vol 2