Setting Cache Size; Defining Aging Timers; Specifying The Activity Timer; Specifying The Inactivity Timer - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - IP SERVICES CONFIGURATION GUIDE 2010-10-01 Configuration Manual

Setting Cache Size

ip flow-cache entries

Defining Aging Timers

ip flow-cache timeout active
Copyright © 2010, Juniper Networks, Inc.
Use the no version to return the sampling interval to its default value, 4 billion.
See ip flow-sampling-mode packet-interval.
Use the ip flow-cache entries command to limit the number of main flow cache entries
for the virtual router (as collected across all line modules that are running J-Flow). After
the cache size exceeds the flow-cache entry limit, the least recently used flow is removed.
The possible flow-cache range is 1,024 – 524,288 entries. The default value is 65,536
entries.
Use to limit J-Flow main flow cache entries.
Example
host1(config)#ip flow-cache entries 80000
Use the no version to return the cache size to its default value, 65535.
See ip flow-cache entries.
After the virtual router creates a flow in the cache, the virtual router can remove the flow
at the expiration of either the active or the inactive timer.

Specifying the Activity Timer

Use the ip flow-cache timeout active command to specify a value for the activity timer.
The activity timer measures the amount of time that the virtual router has been recording
a datagram for a given flow. When this timer expires, the virtual router exports the flow
cache entry from the cache and removes the entry. This process prevents active flows
from remaining in the flow cache, and allows collected data to appear in a timely manner.
The possible range for the activity timer value is 1 – 60 minutes. The default value is 30
minutes.
Use to define the activity timer, in minutes.
Example
host1(config)#ip flow-cache timeout active 50
Use the no version to return the activity timer to its default value (30 minutes).
See ip flow-cache timeout.

Specifying the Inactivity Timer

Use the ip flow-cache timeout inactive command to specify a value for the inactivity
timer. The inactivity timer measures the length of time expired since the virtual router
recorded the last datagram for a given flow. When this timer expires, the virtual router
Chapter 3: Configuring J-Flow Statistics
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