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ホストによるtcpリセットをキャプチャするtcpdump

WebサーバーでTCPリセットが発生する場所を特定しようとしています。次のキャプチャがあります。

tcpdump -fnni bond0:-nnvvS -w dump.pcap 'tcp[tcpflags] & (tcp-rst) !=0'

Wiresharkでpcapを見ると、リセットが表示されます。

    Flags: 0x004 (RST)
    .... .... .1.. = Reset: Set
    .... .... ..0. = Syn: Not set
    .... .... ...0 = Fin: Not set

Window size value: 0
Calculated window size: 0
Window size scaling factor: -1 (unknown)
Checksum: 0x0f2f [validation disabled]
Good Checksum: False
Bad Checksum: False

接続をリセットしたユーザーは表示されません。 tcpdumpにはスイッチがあり、誰が接続をリセットしたのか、そしておそらくその理由を確認できると思います。運が悪いのにいろいろなスイッチを試してみました。

よろしくお願いします。

networkingtcpwiresharktcpdump
6
rahrahruby

_Src Port_および_Dst Port_に注意してください。

_Transmission Control Protocol, Src Port: http (80), Dst Port: norton-lambert (2338), Seq: 1406431331, Len: 0
    Source port: http (80)
    Destination port: norton-lambert (2338)
    [Stream index: 3]
    Sequence number: 1406431331
    Header length: 20 bytes
    Flags: 0x004 (RST)
        000. .... .... = Reserved: Not set
        ...0 .... .... = Nonce: Not set
        .... 0... .... = Congestion Window Reduced (CWR): Not set
        .... .0.. .... = ECN-Echo: Not set
        .... ..0. .... = Urgent: Not set
        .... ...0 .... = Acknowledgment: Not set
        .... .... 0... = Push: Not set
        .... .... .1.. = Reset: Set
            [Expert Info (Chat/Sequence): Connection reset (RST)]
                [Message: Connection reset (RST)]
                [Severity level: Chat]
                [Group: Sequence]
        .... .... ..0. = Syn: Not set
        .... .... ...0 = Fin: Not set
_

Src Port: http (80)は、このRSTパケットがサーバー側から送信されたことを意味します。

それがクライアント側からのものである場合は、理由が表示されます。

_Transmission Control Protocol, Src Port: 57715 (57715), Dst Port: http (80), Seq: 3509013939, Len: 0
    Source port: 57715 (57715)
    Destination port: http (80)
    [Stream index: 32]
    Sequence number: 3509013939
    Acknowledgment Number: 0xd1274db3 [should be 0x00000000 because ACK flag is not set]
        [Expert Info (Warn/Protocol): Acknowledgment number: Broken TCP. The acknowledge field is nonzero while the ACK flag is no
t set]
            [Message: Acknowledgment number: Broken TCP. The acknowledge field is nonzero while the ACK flag is not set]
            [Severity level: Warn]
            [Group: Protocol]
    Header length: 20 bytes
    Flags: 0x004 (RST)
        000. .... .... = Reserved: Not set
        ...0 .... .... = Nonce: Not set
        .... 0... .... = Congestion Window Reduced (CWR): Not set
        .... .0.. .... = ECN-Echo: Not set
        .... ..0. .... = Urgent: Not set
        .... ...0 .... = Acknowledgment: Not set
        .... .... 0... = Push: Not set
        .... .... .1.. = Reset: Set
            [Expert Info (Chat/Sequence): Connection reset (RST)]
                [Message: Connection reset (RST)]
                [Severity level: Chat]
                [Group: Sequence]
        .... .... ..0. = Syn: Not set
        .... .... ...0 = Fin: Not set
_
5
quanta