Riverstone Networks RS Switch Router User Guide Release 8.0 11-17
IP Routing Configuration Guide
Setting Memory Thresholds
The default memory thresholds are shown in
Table 11-1
. You can use the
ip-router global set
memory-threshold
command to change the thresholds.
When a level-1, level-2, or level-3 threshold is reached, the RS may delete routes in the RIB or not add new routes to
the RIB, depending upon the routing protocol. When threshold level-4 is reached (by default, 75% of available memory
used by the RIB), no new routes are added.
Table 11-2
shows what actions the RS takes in updating the RIB when each threshold is reached.
Table 11-1 Default Memory Thresholds
Threshold Level
Percentage of Memory
0
12
03
14
05
62
07
64
Table 11-2 RIB Updates When Memory Threshold is Reached
Route
Protocol
Threshold
Action
OSPF/
IS-IS
level-1
level-2
level-3
level-4
Updates are processed as usual.
RIP
level-1
•
A new RIP route is added only if it is the
only
RIP route to
the given destination.
•
Maximum of 2 routes allowed to a given destination. If there
are more than 2 routes to a given destination, the least
preferred route(s) are deleted.
level-2
•
A new RIP route is added only if is an active RIP route to the
given destination.
level-3
•
Only one route is allowed to a given destination. If there is
more than one route to a given destination, the least preferred
route is deleted.
level-4
No new routes are added.
