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    TCPDump. How to create .pcap file with captured traffic?

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    • R
      ramses.sevilla
      last edited by

      Sorry, I thinked that I had putt the error message.

      It's this message:

      [2.3-RELEASE][admin@pfsense]/root: tcpdump -i em1 -vv ether host host fa:ba:da:00:00:14 -w test.pcap
      tcpdump: syntax error
      [2.3-RELEASE][admin@pfsense]/root:

      If I execute that line in Ubuntu, It's works well.

      If I execute this line in the pfSense, It's works well:

      [2.3-RELEASE][admin@pfsense]/root: tcpdump -i em1 -vv ether host host fa:ba:da:00:00:14
      tcpdump: listening on em1, link-type EN10MB (Ethernet), capture size 65535 bytes
      ^C
      0 packets captured
      204503 packets received by filter
      0 packets dropped by kernel
      [2.3-RELEASE][admin@pfsense]/root:

      Regards

      1 Reply Last reply Reply Quote 0
      • kiokomanK
        kiokoman LAYER 8
        last edited by kiokoman

        this is not what you wrote on the first post,
        right:
        tcpdump -i em1 -vv ether host fa:ba:da:00:00:14 -w test.pcap
        wrong:
        tcpdump -i em1 -vv ether host host fa:ba:da:00:00:14
        also "-w test.cap" missing

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        we must focus on silencing this @guest character. we must make up lies and alter the copyrights !
        Don't forget to Upvote with the 👍 button for any post you find to be helpful.

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        • R
          ramses.sevilla
          last edited by

          @kiokoman sorry,

          It's a Copy / Paste error.

          The correct command and the error are these:

          [2.3-RELEASE][admin@pfsense]/root: tcpdump -i em1 -vv ether host fa:ba:da:00:00:14 -w test.pcap
          tcpdump: syntax error
          [2.3-RELEASE][admin@pfsense]/root:

          Regards

          1 Reply Last reply Reply Quote 0
          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            dude your on pfsense 2.3 -- wow that is OLD and EOL.. you need to update to current

            An intelligent man is sometimes forced to be drunk to spend time with his fools
            If you get confused: Listen to the Music Play
            Please don't Chat/PM me for help, unless mod related
            SG-4860 24.11 | Lab VMs 2.8, 24.11

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            • R
              ramses.sevilla
              last edited by

              @johnpoz, yes, I know that pfSense 2.3 is very old and EOL, but it's an inherited installation.

              I'm trying to clean the residual settings first and to upgrade to the latest version later, first to the 2.4 and to the 2.5 version later.

              Regards

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by johnpoz

                have no idea what version of tcpdump is installed on the 2.3 version - you will have to check your syntax for whatever version that is.

                here is what is on current 2.4.4p3

                [2.4.4-RELEASE][admin@sg4860.local.lan]/root: tcpdump --version
                tcpdump version 4.9.2
                libpcap version 1.8.1
                OpenSSL 1.0.2o-freebsd  27 Mar 2018
                [2.4.4-RELEASE][admin@sg4860.local.lan]/root: 
                

                An intelligent man is sometimes forced to be drunk to spend time with his fools
                If you get confused: Listen to the Music Play
                Please don't Chat/PM me for help, unless mod related
                SG-4860 24.11 | Lab VMs 2.8, 24.11

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                • R
                  ramses.sevilla
                  last edited by

                  Well, the TCPDump versión is:

                  [2.3-RELEASE][admin@pfsense]/root: tcpdump --version
                  tcpdump: illegal option -- -
                  tcpdump version 4.4.0
                  libpcap version 1.4.0
                  Usage: tcpdump [-aAbdDefhHIJKlLnNOpqRStuUvxX] [ -B size ] [ -c count ]
                  		[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]
                  		[ -i interface ] [ -j tstamptype ] [ -M secret ]
                  		[ -r file ] [ -s snaplen ] [ -T type ] [ -V file ] [ -w file ]
                  		[ -W filecount ] [ -y datalinktype ] [ -z command ]
                  		[ -Z user ] [ expression ]
                  [2.3-RELEASE][admin@pfsense]/root:
                  

                  Not has the "--version" option but shows the version.

                  On the other hand, I have already found the problem with the error of TCPDump when I try create a file with the "-w" options.

                  If I put:

                  tcpdump -i em1 -vv -w test.pcap ether host fa:ba:da:00:00:14

                  Instead of:

                  tcpdump -i em1 -vv ether host fa:ba:da:00:00:14 -w test.pcap

                  It works well.

                  [2.3-RELEASE][admin@pfsense]/root: tcpdump -i em1 -vv -w test.pcap ether host fa:ba:da:00:00:14
                  tcpdump: listening on em1, link-type EN10MB (Ethernet), capture size 65535 bytes
                  Got 0
                  ^C0 packets captured
                  485686 packets received by filter
                  0 packets dropped by kernel
                  [2.3-RELEASE][admin@pfsense]/root:
                  

                  Regards and thanks so much.

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    You need to UPDATE... 2.3 is EOL...

                    An intelligent man is sometimes forced to be drunk to spend time with his fools
                    If you get confused: Listen to the Music Play
                    Please don't Chat/PM me for help, unless mod related
                    SG-4860 24.11 | Lab VMs 2.8, 24.11

                    R 1 Reply Last reply Reply Quote 0
                    • R
                      ramses.sevilla @johnpoz
                      last edited by

                      @johnpoz said in TCPDump. How to create .pcap file with captured traffic?:

                      You need to UPDATE... 2.3 is EOL...

                      @johnpoz, yes, I know that pfSense 2.3 is very old and EOL, but it's an inherited installation.

                      I'm trying to clean the residual settings first and to upgrade to the latest version later, first to the 2.4 and to the 2.5 version later.

                      Regards

                      1 Reply Last reply Reply Quote 0
                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by

                        Yeah I saw - just reminding you ;) heheheh

                        An intelligent man is sometimes forced to be drunk to spend time with his fools
                        If you get confused: Listen to the Music Play
                        Please don't Chat/PM me for help, unless mod related
                        SG-4860 24.11 | Lab VMs 2.8, 24.11

                        1 Reply Last reply Reply Quote 0
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