Hello,

I am using IPF v4.1.28 on FreeBSD7. The firewall is working stable and does what is is supposed to do. So no problems there.

The following however, I don't expect: In the ipfstat -t output I see the same connections (source-ip, port <--> destination-ip, port) twice.
For example (part of output ipfstat -t):

Source IP Destination IP ST PR #pkts #bytes ttl 80.60.81.93,1363 195.86.22.59,587 B/6 tcp 173 202746 0:13 80.57.132.26,60464 195.86.22.53,22 4/4 tcp 2393 147824 119:59:59 80.60.81.93,1363 195.86.22.59,587 B/6 tcp 88 101445 0:13 80.57.132.26,60477 195.86.22.59,22 4/4 tcp 1077 64400 119:59:47 (*) 77.162.155.20,49808 195.86.22.50,80 4/4 tcp 203 54140 119:59:17 77.162.155.20,49807 195.86.22.50,80 4/4 tcp 173 45966 119:59:16 80.57.132.26,56603 195.86.22.50,80 4/4 tcp 429 45716 96:09:25 78.171.174.130,1675 195.86.22.54,80 4/4 tcp 145 45292 90:04:42 85.147.196.239,54166 195.86.22.52,80 4/4 tcp 95 34286 119:57:45 83.82.139.218,51157 195.86.22.50,80 B/4 tcp 153 33210 0:12 80.57.132.26,60477 195.86.22.59,22 4/4 tcp 540 32296 119:59:47 (*)

Marked with * is twice.

The output of ipfstat is:

IP states added:
        1862533 TCP
        523994 UDP
        0 ICMP
        49403681 hits
        9612162 misses
        0 bucket full
        0 maximum rule references
        0 maximum
        0 no memory
        1231 bkts in use
        2496 active
        523940 expired
        1860091 closed
State logging enabled

State table bucket statistics:
        1231 in use     
        49% hash efficiency
        1.89% bucket usage
        0 minimal length
        4 maximal length
        2.028 average length

TCP Entries per state
0 1 2 3 4 5 6 7 8 9 10 11 0 0 24 0 1017 556 12 0 10 0 332 491

In this output I see that 1231 buckets are in use. Does that mean that there are 1231 connections for which state-informattion is kept in memory? I see that there are 2496 'active'. Does that mean that there are 2496 hashes which point too the 1231 connections? Is that the (1231/2496) = 49% hash efficiency?

So does ipfstat -t takes the hash-entries and shows the information found in the buckets? Does that explain why the output of ipfstat -t shows connections twice?
Is this behavior by design or should I worry about it?

Greetings,

Rene van Hoek

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