CSS question about reclaiming flows

Unanswered Question

Do resources get consumed on 'flow permanent' flows, even when the referenced TCP connection is closed by a client or server?

I do not see our CSS 'accumulating' any permanent flows even though we have some set.

Appreciate your insight.

The book says: We recommend that when you configure a flow permanent port command you also enable the cmd-sched command to periodically remove the permanent port and allow for cleanup.

I have this problem too.
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didyap Tue, 12/04/2007 - 14:41

CSS uses and automatic garbage-collector for removing inactive flows. To avoid the garbage collection to be performed for specific TCP ports you can use command "flow permanent". On the CSS the user can configure up to 10 permanent ports which will never be garbage collected. The problem of course is that the CSS can then run out of FCBs (Flow Control Blocks) if flows are not properly terminated. So it is recommended running a cmd-sched script with the perm ports so that periodically they can be removed and the older flows cleaned up.

p.sigsworth Thu, 08/28/2008 - 09:21

does anyone have a canned script to use


"flow permanent port1 443"

"no flow permanent port1 443"



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