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Using ipfw I'm configuring pipes, but not actually adding/binding them to a port. For example:

ipfw pipe 1 config bw 100KByte/s
ipfw pipe 2 config bw 200KByte/s

Above I've configured pipes 1 and 2 if not mistaken. Unfortunately, if I run:

ipfw pipe show

I get no output. Except if I actually "ipfw add" the pipes to a rule, then I can see what their configuration is.

The reason I'm asking this question is I'd like to write a script to create pipes but check to see if there are any pipes already configured so I don't overwrite them with my own pipes.

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Are your kernel and userland on the same build? You should get a list of all pipes from ipfw pipe show. – Chris S Jul 9 '10 at 1:40
I think my issue is that I'm trying to "show" pipes that haven't been added, only configured. Running ipfw pipe show after something like ipfw pipe 1 config bw 100KByte/s produces no output for me until I do something like ipfw add pipe ... EDIT: I'm looking for pre-existing pipe configurations basically. I could very well be doing it wrong. – Ben Truyman Jul 9 '10 at 1:58

You first add a rule bound to a pipe then you configure the pipe settings.

You could get a list of ipfw rules that are bound to pipes and derive which pipes exist from that.

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