[syslog-ng] syslog-ng reset connection before data transfer

Evan Rempel erempel at uvic.ca
Thu Mar 2 19:12:42 UTC 2023


I have never tried to send TLS streams from an RFC3164 source. All of my 
sources that could support TLS also support RFC5425.

What I understand you saying is that you have a source that is sending 
RFC54524 messages, using TLS but without the frame header. That is 
completely outside of any RFC combination but that's the story of syslog 
aggregation :-(

I think you could do as you say. Use a network source driver with the 
syslog-protocol flag and enable TLS. This would have to be done on a 
special port so as not to conflict with the RFC5425 framed data streams, 
but it sounds like it would work.

Evan.


On 2023-03-02 10:32, Dragan Zecevic wrote:
>
> Hi Steve and Evan,
> Sorry for the delay, I was on a sick leave.
> Thanks for the ideas.
>
> It seems you are wright, there is an error in front of connection closed:
> Feb 10 15:08:02 xxx syslog-ng[21262]: Invalid frame header; header=''
> Feb 10 15:08:02 xxx syslog-ng[21262]: Syslog connection closed; 
> fd='468', client='AF_INET(x.y.z.w:xxx)', local='AF_INET(0.0.0.0:xxx)'
>
> It seems there is no frame header in incoming syslog messages.
>
> I found this in syslog-ng docs:
>
> syslog-protocol: The syslog-protocol flag instructs the driver to 
> format the messages according to the new IETF syslog protocol standard 
> (RFC5424), but without the frame header. If this flag is enabled, 
> macros used for the message have effect only for the text of the 
> message, the message header is formatted to the new standard. Note 
> that this flag is not needed for the syslog driver, and that the 
> syslog driver automatically adds the frame header to the messages.
>
> syslog-protocol: The syslog-protocol flag specifies that incoming 
> messages are expected to be formatted according to the new IETF syslog 
> protocol standard (RFC5424), but without the frame header. Note that 
> this flag is not needed for the syslog driver, which handles only 
> messages that have a frame header.
>
> As I understand syslog driver for RFC5425 doesn't support messages 
> without frame header.
>
> So should I then use network driver with syslog-protocol flag in 
> combination with RFC3164 messages?
>
> Thank you.
>
> Br,
> Dragan
>
> ------------------------------------------------------------------------
> *From:* syslog-ng <syslog-ng-bounces at lists.balabit.hu> on behalf of 
> Evan Rempel <erempel at uvic.ca>
> *Sent:* Thursday, February 23, 2023 2:17 PM
> *To:* syslog-ng at lists.balabit.hu <syslog-ng at lists.balabit.hu>
> *Subject:* Re: [syslog-ng] syslog-ng reset connection before data 
> transfer
> I had an issue with they symptom of the connection closing as the 
> first message was sent. If eventually came down to the packet framing. 
> When using syslog protocol (RFC 5424/5425) you must use framing. 
> Without it syslog-ng drops the connection.
>
> As Steve says, look for errors from the receiving syslog-ng process. 
> There should be an error immediately preceding the closed connection.
>
> Evan.
>
> On 2023-02-23 05:33, Steve Bernacki wrote:
>>
>> Dragan,
>>
>>
>> 1) Are you seeing any error or diagnostic message immediately before 
>> "Syslog connection closed"? If a log message immediately precedes 
>> this message with the same timestamp, it's usually related even 
>> though there's nothing in the two entries to tie them together.
>>
>>
>> 2) Are the clients running syslog-ng?
>>
>>
>> 3) Any other similarities with the clients that are not working, e.g. 
>> on the same network segment etc? Could there be some type of network 
>> IDS device sniping these connections?
>>
>>
>> Steve
>>
>>
>> On 2/23/2023 3:40 AM, Dragan Zecevic wrote:
>>>
>>>
>>> Hi again,
>>> Does somebody have an idea on this?
>>>
>>> Thank you.
>>>
>>> Br,
>>> Dragan
>>>
>>> ------------------------------------------------------------------------
>>> *From:* syslog-ng <syslog-ng-bounces at lists.balabit.hu> 
>>> <mailto:syslog-ng-bounces at lists.balabit.hu> on behalf of Dragan 
>>> Zecevic <dragan.zecevic at live.com> <mailto:dragan.zecevic at live.com>
>>> *Sent:* Tuesday, February 14, 2023 2:33 PM
>>> *To:* syslog-ng at lists.balabit.hu <mailto:syslog-ng at lists.balabit.hu> 
>>> <syslog-ng at lists.balabit.hu> <mailto:syslog-ng at lists.balabit.hu>
>>> *Subject:* [syslog-ng] syslog-ng reset connection before data transfer
>>> Hi everybody,
>>> I hope you are well.
>>>
>>> I was hoping if you can help me with some issue.
>>> I am trying to collect logs from some servers via syslog.
>>> TLS session seems to be established - handshake, certs, ciphers all 
>>> looking ok.
>>> But when data need to be send it seems syslog-ng server disconnects 
>>> the session from some reason.
>>>
>>> In /var/log/messages I can only see start/stop messages even after 
>>> turning on verbose logging:
>>>
>>> Feb 10 16:11:48 xxx syslog-ng[21262]: Syslog connection accepted; 
>>> fd='175', client='AF_INET(x.y.w.z:34986)', local='AF_INET(0.0.0.0:xxx)'
>>> Feb 10 16:11:49 xxx syslog-ng[21262]: Syslog connection closed; 
>>> fd='175', client='AF_INET(x.y.w.z:34986)', local='AF_INET(0.0.0.0:xxx)'
>>>
>>> This is the configuration I am using:
>>>
>>> source s_xxx {
>>>     syslog(
>>>         ip(0.0.0.0)
>>>         port(xxx)
>>> transport("tls")
>>>         tls(
>>> key-file("/etc/syslog-ng/key.d/xxx.key")
>>> cert-file("/etc/syslog-ng/cert.d/xxx.cer")
>>> ca-dir("/etc/syslog-ng/ca.d")
>>> peer-verify(required-trusted)
>>> cipher-suite("xxx...xxx")
>>>         )
>>> flags(store-raw-message)
>>>     );
>>> };
>>>
>>> filter filter_xxx {
>>>
>>> host("xxx") ... or host("xxx");
>>> };
>>>
>>> destination folder_xxx {
>>>
>>> file(
>>> "/var/log/xxx/${R_YEAR}${R_MONTH}${R_DAY}/${SOURCEIP}_${HOST}_${R_HOUR}.log"
>>>     template("${RAWMSG}\n")
>>>     dir-group(xxx)
>>>     dir-perm(0650)
>>>     group(xxx)
>>>                 );
>>> };
>>>
>>> log {
>>> source(s_xxx); filter(filter_xxx); destination(folder_xxx); 
>>> flags(flow-control);
>>> };
>>>
>>>
>>> And bellow is last part of the session captured with tcpdump from 
>>> source side.
>>> It is interesting to me that there is 1h offset comparing to 
>>> /var/log/messages on syslog-ng. Src and dst server are in same 
>>> environment.
>>>
>>>
>>> 24    2023-02-10 
>>> 15:11:49,073335    x.y.w.z     x.y.w.z     TLSv1.2     445   Application 
>>> Data
>>> Frame 24: 445 bytes on wire (3560 bits), 445 bytes captured (3560 bits)
>>>     Encapsulation type: Ethernet (1)
>>>     Arrival Time: Feb 10, 2023 15:11:49.073335000 Central Europe 
>>> Standard Time
>>>     [Time shift for this packet: 0.000000000 seconds]
>>>     Epoch Time: 1676038309.073335000 seconds
>>>     [Time delta from previous captured frame: 0.906559000 seconds]
>>>     [Time delta from previous displayed frame: 0.906559000 seconds]
>>>     [Time since reference or first frame: 6.775677000 seconds]
>>>     Frame Number: 24
>>>     Frame Length: 445 bytes (3560 bits)
>>>     Capture Length: 445 bytes (3560 bits)
>>>     [Frame is marked: False]
>>>     [Frame is ignored: False]
>>>     [Protocols in frame: eth:ethertype:ip:tcp:tls]
>>>     [Coloring Rule Name: TCP]
>>>     [Coloring Rule String: tcp]
>>> Ethernet II, Src: xxx, Dst: xxx
>>>     Destination: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Source: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Type: IPv4 (0x0800)
>>> Internet Protocol Version 4, Src: x.y.z.w, Dst: x.y.z.w
>>>     0100 .... = Version: 4
>>>     .... 0101 = Header Length: 20 bytes (5)
>>>     Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
>>>         0000 00.. = Differentiated Services Codepoint: Default (0)
>>>         .... ..00 = Explicit Congestion Notification: Not 
>>> ECN-Capable Transport (0)
>>>     Total Length: 431
>>>     Identification: 0xeebc (61116)
>>>     010. .... = Flags: 0x2, Don't fragment
>>>         0... .... = Reserved bit: Not set
>>>         .1.. .... = Don't fragment: Set
>>>         ..0. .... = More fragments: Not set
>>>     ...0 0000 0000 0000 = Fragment Offset: 0
>>>     Time to Live: 64
>>>     Protocol: TCP (6)
>>>     Header Checksum: 0x0a89 [validation disabled]
>>>     [Header checksum status: Unverified]
>>>     Source Address: x.y.z.w
>>>     Destination Address: x.y.z.w
>>> Transmission Control Protocol, Src Port: 34986, Dst Port: xxx, Seq: 
>>> 2380, Ack: 5750, Len: 391
>>>     Source Port: 34986
>>>     Destination Port: xxx
>>>     [Stream index: 1]
>>>     [Conversation completeness: Complete, WITH_DATA (63)]
>>>     [TCP Segment Len: 391]
>>>     Sequence Number: 2380    (relative sequence number)
>>>     Sequence Number (raw): 2630184540
>>>     [Next Sequence Number: 2771    (relative sequence number)]
>>>     Acknowledgment Number: 5750    (relative ack number)
>>>     Acknowledgment number (raw): 2509794849
>>>     0101 .... = Header Length: 20 bytes (5)
>>>     Flags: 0x018 (PSH, ACK)
>>>         000. .... .... = Reserved: Not set
>>>         ...0 .... .... = Accurate ECN: Not set
>>>         .... 0... .... = Congestion Window Reduced: Not set
>>>         .... .0.. .... = ECN-Echo: Not set
>>>         .... ..0. .... = Urgent: Not set
>>>         .... ...1 .... = Acknowledgment: Set
>>>         .... .... 1... = Push: Set
>>>         .... .... .0.. = Reset: Not set
>>>         .... .... ..0. = Syn: Not set
>>>         .... .... ...0 = Fin: Not set
>>>         [TCP Flags: ·······AP···]
>>>     Window: 318
>>>     [Calculated window size: 40704]
>>>     [Window size scaling factor: 128]
>>>     Checksum: 0x41a5 [unverified]
>>>     [Checksum Status: Unverified]
>>>     Urgent Pointer: 0
>>>     [Timestamps]
>>>         [Time since first frame in this TCP stream: 1.007330000 seconds]
>>>         [Time since previous frame in this TCP stream: 0.906559000 
>>> seconds]
>>>     [SEQ/ACK analysis]
>>>         [iRTT: 0.003010000 seconds]
>>>         [Bytes in flight: 391]
>>>         [Bytes sent since last PSH flag: 391]
>>>     TCP payload (391 bytes)
>>> Transport Layer Security
>>>     TLSv1.2 Record Layer: Application Data Protocol: Application Data
>>>         Content Type: Application Data (23)
>>>         Version: TLS 1.2 (0x0303)
>>>         Length: 386
>>>         Encrypted Application Data: 
>>> 000000000000000146f17ff0e884c81f9317ba9e01c3b48763944e3905fb27fc96ce76fc…
>>>
>>>
>>> 25    2023-02-10 
>>> 15:11:49,076214    x.y.z.w     x.y.z.w     TCP   60    xxx → 34986 
>>> [FIN, ACK] Seq=5750 Ack=2771 Win=65536 Len=0
>>> Frame 25: 60 bytes on wire (480 bits), 60 bytes captured (480 bits)
>>>     Encapsulation type: Ethernet (1)
>>>     Arrival Time: Feb 10, 2023 15:11:49.076214000 Central Europe 
>>> Standard Time
>>>     [Time shift for this packet: 0.000000000 seconds]
>>>     Epoch Time: 1676038309.076214000 seconds
>>>     [Time delta from previous captured frame: 0.002879000 seconds]
>>>     [Time delta from previous displayed frame: 0.002879000 seconds]
>>>     [Time since reference or first frame: 6.778556000 seconds]
>>>     Frame Number: 25
>>>     Frame Length: 60 bytes (480 bits)
>>>     Capture Length: 60 bytes (480 bits)
>>>     [Frame is marked: False]
>>>     [Frame is ignored: False]
>>>     [Protocols in frame: eth:ethertype:ip:tcp]
>>>     [Coloring Rule Name: TCP SYN/FIN]
>>>     [Coloring Rule String: tcp.flags & 0x02 || tcp.flags.fin == 1]
>>> Ethernet II, Src: xxx, Dst: xxx
>>>     Destination: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Source: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Type: IPv4 (0x0800)
>>>     Trailer: 000085725dce
>>> Internet Protocol Version 4, Src: x.y.z.w, Dst: x.y.z.w
>>>     0100 .... = Version: 4
>>>     .... 0101 = Header Length: 20 bytes (5)
>>>     Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
>>>         0000 00.. = Differentiated Services Codepoint: Default (0)
>>>         .... ..00 = Explicit Congestion Notification: Not 
>>> ECN-Capable Transport (0)
>>>     Total Length: 40
>>>     Identification: 0xea10 (59920)
>>>     010. .... = Flags: 0x2, Don't fragment
>>>         0... .... = Reserved bit: Not set
>>>         .1.. .... = Don't fragment: Set
>>>         ..0. .... = More fragments: Not set
>>>     ...0 0000 0000 0000 = Fragment Offset: 0
>>>     Time to Live: 52
>>>     Protocol: TCP (6)
>>>     Header Checksum: 0x1cbc [validation disabled]
>>>     [Header checksum status: Unverified]
>>>     Source Address: x.y.z.w
>>>     Destination Address: x.y.z.w
>>> Transmission Control Protocol, Src Port: xxx, Dst Port: 34986, Seq: 
>>> 5750, Ack: 2771, Len: 0
>>>     Source Port: xxx
>>>     Destination Port: 34986
>>>     [Stream index: 1]
>>>     [Conversation completeness: Complete, WITH_DATA (63)]
>>>     [TCP Segment Len: 0]
>>>     Sequence Number: 5750    (relative sequence number)
>>>     Sequence Number (raw): 2509794849
>>>     [Next Sequence Number: 5751    (relative sequence number)]
>>>     Acknowledgment Number: 2771    (relative ack number)
>>>     Acknowledgment number (raw): 2630184931
>>>     0101 .... = Header Length: 20 bytes (5)
>>>     Flags: 0x011 (FIN, ACK)
>>>         000. .... .... = Reserved: Not set
>>>         ...0 .... .... = Accurate ECN: Not set
>>>         .... 0... .... = Congestion Window Reduced: Not set
>>>         .... .0.. .... = ECN-Echo: Not set
>>>         .... ..0. .... = Urgent: Not set
>>>         .... ...1 .... = Acknowledgment: Set
>>>         .... .... 0... = Push: Not set
>>>         .... .... .0.. = Reset: Not set
>>>         .... .... ..0. = Syn: Not set
>>>         .... .... ...1 = Fin: Set
>>>         [TCP Flags: ·······A···F]
>>>     Window: 4
>>>     [Calculated window size: 65536]
>>>     [Window size scaling factor: 16384]
>>>     Checksum: 0xc512 [unverified]
>>>     [Checksum Status: Unverified]
>>>     Urgent Pointer: 0
>>>     [Timestamps]
>>>         [Time since first frame in this TCP stream: 1.010209000 seconds]
>>>         [Time since previous frame in this TCP stream: 0.002879000 
>>> seconds]
>>>     [SEQ/ACK analysis]
>>>         [This is an ACK to the segment in frame: 24]
>>>         [The RTT to ACK the segment was: 0.002879000 seconds]
>>>         [iRTT: 0.003010000 seconds]
>>>
>>>
>>> 26    2023-02-10 
>>> 15:11:49,117776    x.y.z.w     x.y.z.w     TCP   54    34986 → xxx 
>>> [ACK] Seq=2771 Ack=5751 Win=40704 Len=0
>>> Frame 26: 54 bytes on wire (432 bits), 54 bytes captured (432 bits)
>>>     Encapsulation type: Ethernet (1)
>>>     Arrival Time: Feb 10, 2023 15:11:49.117776000 Central Europe 
>>> Standard Time
>>>     [Time shift for this packet: 0.000000000 seconds]
>>>     Epoch Time: 1676038309.117776000 seconds
>>>     [Time delta from previous captured frame: 0.041562000 seconds]
>>>     [Time delta from previous displayed frame: 0.041562000 seconds]
>>>     [Time since reference or first frame: 6.820118000 seconds]
>>>     Frame Number: 26
>>>     Frame Length: 54 bytes (432 bits)
>>>     Capture Length: 54 bytes (432 bits)
>>>     [Frame is marked: False]
>>>     [Frame is ignored: False]
>>>     [Protocols in frame: eth:ethertype:ip:tcp]
>>>     [Coloring Rule Name: TCP]
>>>     [Coloring Rule String: tcp]
>>> Ethernet II, Src: Mellanox_69:6f:47 (1c:34:da:69:6f:47), Dst: 
>>> ICANNIAN_00:40:20 (00:00:5e:00:40:20)
>>>     Destination: ICANNIAN_00:40:20 (00:00:5e:00:40:20)
>>>         Address: ICANNIAN_00:40:20 (00:00:5e:00:40:20)
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Source: Mellanox_69:6f:47 (1c:34:da:69:6f:47)
>>>         Address: Mellanox_69:6f:47 (1c:34:da:69:6f:47)
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Type: IPv4 (0x0800)
>>> Internet Protocol Version 4, Src: x.y.z.w, Dst: x.y.z.w
>>>     0100 .... = Version: 4
>>>     .... 0101 = Header Length: 20 bytes (5)
>>>     Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
>>>         0000 00.. = Differentiated Services Codepoint: Default (0)
>>>         .... ..00 = Explicit Congestion Notification: Not 
>>> ECN-Capable Transport (0)
>>>     Total Length: 40
>>>     Identification: 0xeebd (61117)
>>>     010. .... = Flags: 0x2, Don't fragment
>>>         0... .... = Reserved bit: Not set
>>>         .1.. .... = Don't fragment: Set
>>>         ..0. .... = More fragments: Not set
>>>     ...0 0000 0000 0000 = Fragment Offset: 0
>>>     Time to Live: 64
>>>     Protocol: TCP (6)
>>>     Header Checksum: 0x0c0f [validation disabled]
>>>     [Header checksum status: Unverified]
>>>     Source Address: x.y.z.w
>>>     Destination Address: x.y.z.w
>>> Transmission Control Protocol, Src Port: 34986, Dst Port: xxx, Seq: 
>>> 2771, Ack: 5751, Len: 0
>>>     Source Port: 34986
>>>     Destination Port: xxx
>>>     [Stream index: 1]
>>>     [Conversation completeness: Complete, WITH_DATA (63)]
>>>     [TCP Segment Len: 0]
>>>     Sequence Number: 2771    (relative sequence number)
>>>     Sequence Number (raw): 2630184931
>>>     [Next Sequence Number: 2771    (relative sequence number)]
>>>     Acknowledgment Number: 5751    (relative ack number)
>>>     Acknowledgment number (raw): 2509794850
>>>     0101 .... = Header Length: 20 bytes (5)
>>>     Flags: 0x010 (ACK)
>>>         000. .... .... = Reserved: Not set
>>>         ...0 .... .... = Accurate ECN: Not set
>>>         .... 0... .... = Congestion Window Reduced: Not set
>>>         .... .0.. .... = ECN-Echo: Not set
>>>         .... ..0. .... = Urgent: Not set
>>>         .... ...1 .... = Acknowledgment: Set
>>>         .... .... 0... = Push: Not set
>>>         .... .... .0.. = Reset: Not set
>>>         .... .... ..0. = Syn: Not set
>>>         .... .... ...0 = Fin: Not set
>>>         [TCP Flags: ·······A····]
>>>     Window: 318
>>>     [Calculated window size: 40704]
>>>     [Window size scaling factor: 128]
>>>     Checksum: 0x401e [unverified]
>>>     [Checksum Status: Unverified]
>>>     Urgent Pointer: 0
>>>     [Timestamps]
>>>         [Time since first frame in this TCP stream: 1.051771000 seconds]
>>>         [Time since previous frame in this TCP stream: 0.041562000 
>>> seconds]
>>>     [SEQ/ACK analysis]
>>>         [This is an ACK to the segment in frame: 25]
>>>         [The RTT to ACK the segment was: 0.041562000 seconds]
>>>         [iRTT: 0.003010000 seconds]
>>>
>>>
>>>
>>> 27    2023-02-10 
>>> 15:12:10,183395    x.y.w.z     x.y.w.z     TLSv1.2     457   Application 
>>> Data
>>> Frame 27: 457 bytes on wire (3656 bits), 457 bytes captured (3656 bits)
>>>     Encapsulation type: Ethernet (1)
>>>     Arrival Time: Feb 10, 2023 15:12:10.183395000 Central Europe 
>>> Standard Time
>>>     [Time shift for this packet: 0.000000000 seconds]
>>>     Epoch Time: 1676038330.183395000 seconds
>>>     [Time delta from previous captured frame: 21.065619000 seconds]
>>>     [Time delta from previous displayed frame: 21.065619000 seconds]
>>>     [Time since reference or first frame: 27.885737000 seconds]
>>>     Frame Number: 27
>>>     Frame Length: 457 bytes (3656 bits)
>>>     Capture Length: 457 bytes (3656 bits)
>>>     [Frame is marked: False]
>>>     [Frame is ignored: False]
>>>     [Protocols in frame: eth:ethertype:ip:tcp:tls]
>>>     [Coloring Rule Name: TCP]
>>>     [Coloring Rule String: tcp]
>>> Ethernet II, Src: xxx, Dst: xxx
>>>     Destination: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Source: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Type: IPv4 (0x0800)
>>> Internet Protocol Version 4, Src: x.y.w.z, Dst: x.y.w.z
>>>     0100 .... = Version: 4
>>>     .... 0101 = Header Length: 20 bytes (5)
>>>     Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
>>>         0000 00.. = Differentiated Services Codepoint: Default (0)
>>>         .... ..00 = Explicit Congestion Notification: Not 
>>> ECN-Capable Transport (0)
>>>     Total Length: 443
>>>     Identification: 0xeebe (61118)
>>>     010. .... = Flags: 0x2, Don't fragment
>>>         0... .... = Reserved bit: Not set
>>>         .1.. .... = Don't fragment: Set
>>>         ..0. .... = More fragments: Not set
>>>     ...0 0000 0000 0000 = Fragment Offset: 0
>>>     Time to Live: 64
>>>     Protocol: TCP (6)
>>>     Header Checksum: 0x0a7b [validation disabled]
>>>     [Header checksum status: Unverified]
>>>     Source Address: x.y.w.z
>>>     Destination Address: x.y.w.z
>>> Transmission Control Protocol, Src Port: 34986, Dst Port: xxx, Seq: 
>>> 2771, Ack: 5751, Len: 403
>>>     Source Port: 34986
>>>     Destination Port: xxx
>>>     [Stream index: 1]
>>>     [Conversation completeness: Complete, WITH_DATA (63)]
>>>     [TCP Segment Len: 403]
>>>     Sequence Number: 2771    (relative sequence number)
>>>     Sequence Number (raw): 2630184931
>>>     [Next Sequence Number: 3174    (relative sequence number)]
>>>     Acknowledgment Number: 5751    (relative ack number)
>>>     Acknowledgment number (raw): 2509794850
>>>     0101 .... = Header Length: 20 bytes (5)
>>>     Flags: 0x018 (PSH, ACK)
>>>         000. .... .... = Reserved: Not set
>>>         ...0 .... .... = Accurate ECN: Not set
>>>         .... 0... .... = Congestion Window Reduced: Not set
>>>         .... .0.. .... = ECN-Echo: Not set
>>>         .... ..0. .... = Urgent: Not set
>>>         .... ...1 .... = Acknowledgment: Set
>>>         .... .... 1... = Push: Set
>>>         .... .... .0.. = Reset: Not set
>>>         .... .... ..0. = Syn: Not set
>>>         .... .... ...0 = Fin: Not set
>>>         [TCP Flags: ·······AP···]
>>>     Window: 318
>>>     [Calculated window size: 40704]
>>>     [Window size scaling factor: 128]
>>>     Checksum: 0x41b1 [unverified]
>>>     [Checksum Status: Unverified]
>>>     Urgent Pointer: 0
>>>     [Timestamps]
>>>         [Time since first frame in this TCP stream: 22.117390000 
>>> seconds]
>>>         [Time since previous frame in this TCP stream: 21.065619000 
>>> seconds]
>>>     [SEQ/ACK analysis]
>>>         [iRTT: 0.003010000 seconds]
>>>         [Bytes in flight: 403]
>>>         [Bytes sent since last PSH flag: 403]
>>>     TCP payload (403 bytes)
>>> Transport Layer Security
>>>     TLSv1.2 Record Layer: Application Data Protocol: Application Data
>>>         Content Type: Application Data (23)
>>>         Version: TLS 1.2 (0x0303)
>>>         Length: 398
>>>         Encrypted Application Data: 
>>> 0000000000000002be4aae5822b205849734ad881717619991987bc9817d0b0417781265…
>>>
>>>
>>> 28    2023-02-10 
>>> 15:12:10,185930    x.y.w.z     x.y.w.z     TCP   60    xxx → 34986 
>>> [RST] Seq=5751 Win=0 Len=0
>>> Frame 28: 60 bytes on wire (480 bits), 60 bytes captured (480 bits)
>>>     Encapsulation type: Ethernet (1)
>>>     Arrival Time: Feb 10, 2023 15:12:10.185930000 Central Europe 
>>> Standard Time
>>>     [Time shift for this packet: 0.000000000 seconds]
>>>     Epoch Time: 1676038330.185930000 seconds
>>>     [Time delta from previous captured frame: 0.002535000 seconds]
>>>     [Time delta from previous displayed frame: 0.002535000 seconds]
>>>     [Time since reference or first frame: 27.888272000 seconds]
>>>     Frame Number: 28
>>>     Frame Length: 60 bytes (480 bits)
>>>     Capture Length: 60 bytes (480 bits)
>>>     [Frame is marked: False]
>>>     [Frame is ignored: False]
>>>     [Protocols in frame: eth:ethertype:ip:tcp]
>>>     [Coloring Rule Name: TCP RST]
>>>     [Coloring Rule String: tcp.flags.reset eq 1]
>>> Ethernet II, Src: xxx, Dst: xxx
>>>     Destination: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Source: xxx
>>>         Address: xxx
>>>         .... ..0. .... .... .... .... = LG bit: Globally unique 
>>> address (factory default)
>>>         .... ...0 .... .... .... .... = IG bit: Individual address 
>>> (unicast)
>>>     Type: IPv4 (0x0800)
>>>     Trailer: 00003b22a540
>>> Internet Protocol Version 4, Src: x.y.w.z, Dst: x.y.w.z
>>>     0100 .... = Version: 4
>>>     .... 0101 = Header Length: 20 bytes (5)
>>>     Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
>>>         0000 00.. = Differentiated Services Codepoint: Default (0)
>>>         .... ..00 = Explicit Congestion Notification: Not 
>>> ECN-Capable Transport (0)
>>>     Total Length: 40
>>>     Identification: 0xd52f (54575)
>>>     010. .... = Flags: 0x2, Don't fragment
>>>         0... .... = Reserved bit: Not set
>>>         .1.. .... = Don't fragment: Set
>>>         ..0. .... = More fragments: Not set
>>>     ...0 0000 0000 0000 = Fragment Offset: 0
>>>     Time to Live: 52
>>>     Protocol: TCP (6)
>>>     Header Checksum: 0x319d [validation disabled]
>>>     [Header checksum status: Unverified]
>>>     Source Address: x.y.w.z
>>>     Destination Address: x.y.w.z
>>> Transmission Control Protocol, Src Port: xxx, Dst Port: 34986, Seq: 
>>> 5751, Len: 0
>>>     Source Port: xxx
>>>     Destination Port: 34986
>>>     [Stream index: 1]
>>>     [Conversation completeness: Complete, WITH_DATA (63)]
>>>     [TCP Segment Len: 0]
>>>     Sequence Number: 5751    (relative sequence number)
>>>     Sequence Number (raw): 2509794850
>>>     [Next Sequence Number: 5751    (relative sequence number)]
>>>     Acknowledgment Number: 0
>>>     Acknowledgment number (raw): 0
>>>     0101 .... = Header Length: 20 bytes (5)
>>>     Flags: 0x004 (RST)
>>>         000. .... .... = Reserved: Not set
>>>         ...0 .... .... = Accurate ECN: Not set
>>>         .... 0... .... = Congestion Window Reduced: Not set
>>>         .... .0.. .... = ECN-Echo: Not set
>>>         .... ..0. .... = Urgent: Not set
>>>         .... ...0 .... = Acknowledgment: Not set
>>>         .... .... 0... = Push: Not set
>>>         .... .... .1.. = Reset: Set
>>>         .... .... ..0. = Syn: Not set
>>>         .... .... ...0 = Fin: Not set
>>>         [TCP Flags: ·········R··]
>>>     Window: 0
>>>     [Calculated window size: 0]
>>>     [Window size scaling factor: 16384]
>>>     Checksum: 0xd1cb [unverified]
>>>     [Checksum Status: Unverified]
>>>     Urgent Pointer: 0
>>>     [Timestamps]
>>>         [Time since first frame in this TCP stream: 22.119925000 
>>> seconds]
>>>         [Time since previous frame in this TCP stream: 0.002535000 
>>> seconds]
>>>
>>> I have other log collections working fine with TLS.
>>>
>>> Can you please give me some hint what could cause this?
>>>
>>> Thank you.
>>>
>>> Br,
>>> Dragan
>>>
>
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