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    Can't connect to Microsoft SQL via OpenVPN

    Scheduled Pinned Locked Moved OpenVPN
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    • C
      cmb
      last edited by

      You have bidirectional traffic in the other capture, do the same one there again with full verbosity.

      1 Reply Last reply Reply Quote 0
      • M
        malt0r
        last edited by 

        08:56:05.792804 AF IPv4 (2), length 56: (tos 0x0, ttl 128, id 22691, offset 0, flags [DF], proto TCP (6), length 52)
    192.168.253.6.49892 > 192.168.1.245.1433: Flags [s], cksum 0x1dcb (correct), seq 1317837410, win 8192, options [mss 1350,nop,wscale 2,nop,nop,sackOK], length 0
08:56:05.794406 AF IPv4 (2), length 44: (tos 0x0, ttl 127, id 24479, offset 0, flags [DF], proto TCP (6), length 40)
    192.168.1.245.1433 > 192.168.253.6.49892: Flags [R.], cksum 0x7e16 (correct), seq 0, ack 1317837411, win 0, length 0
08:56:06.313799 AF IPv4 (2), length 56: (tos 0x0, ttl 128, id 22692, offset 0, flags [DF], proto TCP (6), length 52)
    192.168.253.6.49892 > 192.168.1.245.1433: Flags [s], cksum 0x1dcb (correct), seq 1317837410, win 8192, options [mss 1350,nop,wscale 2,nop,nop,sackOK], length 0
08:56:06.314113 AF IPv4 (2), length 44: (tos 0x0, ttl 127, id 24480, offset 0, flags [DF], proto TCP (6), length 40)
    192.168.1.245.1433 > 192.168.253.6.49892: Flags [R.], cksum 0x7e16 (correct), seq 0, ack 1, win 0, length 0
08:56:06.845949 AF IPv4 (2), length 52: (tos 0x0, ttl 128, id 22693, offset 0, flags [DF], proto TCP (6), length 48)
    192.168.253.6.49892 > 192.168.1.245.1433: Flags [s], cksum 0x31d4 (correct), seq 1317837410, win 8192, options [mss 1350,nop,nop,sackOK], length 0
08:56:06.846406 AF IPv4 (2), length 44: (tos 0x0, ttl 127, id 24481, offset 0, flags [DF], proto TCP (6), length 40)
    192.168.1.245.1433 > 192.168.253.6.49892: Flags [R.], cksum 0x7e16 (correct), seq 0, ack 1, win 0, length 0

Does that suit you?[/s][/s][/s]
        1 Reply Last reply Reply Quote 0
        • C
          cmb
          last edited by

          got botched by the forum formatting, fixed your post to quote it as code.

          That's definitely more helpful. You're sending a SYN, and getting a RST back. That means something is actively rejecting your connection attempt. Unless you have a reject rule configured in pfSense that's blocking the traffic, it's coming from somewhere else. Either the server isn't listening on that port (that's what happens when you try to connect to a port that isn't open), or something is rejecting the connection. Your earlier packet capture seems to suggest that wouldn't be coming from the server, but it's entirely possible that capture is missing something that's actually there, not familiar enough with what you were using there to know for sure.

          The last time I saw exactly what you were seeing there with a SYN responded to with a RST, just last week actually, it was because the MSSQL server wasn't listening on 1433. Check netstat -a on the server, see if it is actually listening.

          1 Reply Last reply Reply Quote 0
          • M
            malt0r
            last edited by 

             Proto  Lokale Adresse         Remoteadresse          Status
 TCP    0.0.0.0:80             SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:135            SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:443            SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:445            SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:1433           SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:3306           SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:3389           SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:6050           SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:10000          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:41523          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:47001          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:49152          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:49153          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:49154          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:49155          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:49200          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:49206          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:49849          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:58754          SRV-2K8DB:0            ABHÖREN
 TCP    0.0.0.0:59188          SRV-2K8DB:0            ABHÖREN
 TCP    127.0.0.1:49850        SRV-2K8DB:0            ABHÖREN
 TCP    127.0.0.1:58755        SRV-2K8DB:0            ABHÖREN
 TCP    127.0.0.1:59189        SRV-2K8DB:0            ABHÖREN
 TCP    192.168.1.245:139      SRV-2K8DB:0            ABHÖREN
 TCP    192.168.1.245:445      DE-EXT-MOB-005:65525   HERGESTE
 TCP    192.168.1.245:3389     DE-EXT-MOB-005:65475   HERGESTE
 TCP    192.168.1.245:52153    SRV-2K8AD:49155        HERGESTE
 TCP    192.168.1.245:52843    SRV-2K8AD:netbios-ssn  WARTEND
 TCP    192.168.1.245:52844    SRV-2K8AD:netbios-ssn  WARTEND
 TCP    192.168.1.245:52845    SRV-2K8AD:netbios-ssn  WARTEND
 TCP    192.168.1.245:52848    SRV-2K8AD:epmap        HERGESTE
 TCP    192.168.1.245:52849    SRV-2K8AD:49155        HERGESTE
 TCP    192.168.1.245:59188    SRV-David12-2:53009    HERGESTE
 TCP    [::]:80                SRV-2K8DB:0            ABHÖREN
 TCP    [::]:135               SRV-2K8DB:0            ABHÖREN
 TCP    [::]:443               SRV-2K8DB:0            ABHÖREN
 TCP    [::]:445               SRV-2K8DB:0            ABHÖREN
 TCP    [::]:1433              SRV-2K8DB:0            ABHÖREN
 TCP    [::]:3389              SRV-2K8DB:0            ABHÖREN
 TCP    [::]:10000             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:47001             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:49152             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:49153             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:49154             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:49155             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:49200             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:49206             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:49849             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:58754             SRV-2K8DB:0            ABHÖREN
 TCP    [::]:59188             SRV-2K8DB:0            ABHÖREN
 TCP    [::1]:49850            SRV-2K8DB:0            ABHÖREN
 TCP    [::1]:58755            SRV-2K8DB:0            ABHÖREN
 TCP    [::1]:59189            SRV-2K8DB:0            ABHÖREN
 UDP    0.0.0.0:123            *:*
 UDP    0.0.0.0:500            *:*
 UDP    0.0.0.0:1434           *:*
 UDP    0.0.0.0:4500           *:*
 UDP    0.0.0.0:5355           *:*
 UDP    0.0.0.0:6050           *:*
 UDP    0.0.0.0:41524          *:*
 UDP    0.0.0.0:61245          *:*
 UDP    127.0.0.1:50306        *:*
 UDP    127.0.0.1:50823        *:*
 UDP    127.0.0.1:53350        *:*
 UDP    127.0.0.1:55764        *:*
 UDP    127.0.0.1:59267        *:*
 UDP    127.0.0.1:61244        *:*
 UDP    192.168.1.245:137      *:*
 UDP    192.168.1.245:138      *:*
 UDP    [::]:123               *:*
 UDP    [::]:500               *:*
 UDP    [::]:1434              *:*
 UDP    [::]:4500              *:*
 UDP    [::]:5355              *:*
 UDP    [fe80::a5ed:29ea:f1db:35ca%11]:546  *:*

            as you can see the SQL Server is listening on port 1433 on all IP's.

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            • M
              Metu69salemi
              last edited by

              And this server has no software based firewall solution?
              I have feeling of two most possible problems here and solutions are easy:

              1. Check servers gateway-address that it's taking right gateway
              2. software based firewall blocks this openvpn connection, because it's coming from another subnet
              1 Reply Last reply Reply Quote 0
              • M
                malt0r
                last edited by

                as you can see in my attached screens the windows firewall is turned of and the gateway of the sevrer is the ip of the pfsense box (192.168.1.1)

                firewall.png
                firewall.png_thumb
                ![ip config.png](/public/imported_attachments/1/ip config.png)
                ![ip config.png_thumb](/public/imported_attachments/1/ip config.png_thumb)

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                • M
                  Metu69salemi
                  last edited by

                  can you test that you route into this sql-database within your inhouse? Is there possibility, that this software just wont work from another subnet

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    So you are trying to connect to a named instance - unless this is the only instance running on the server it would not be on 1433 but a dynamic port.  See the link I posted.

                    or a named instance that is the only instance running on the computer. (Named instances have special considerations. See Dynamic Ports later in this topic.)

                    By default, named instances (including SQL Server Express) use dynamic ports. That means that every time that the Database Engine starts, it identifies an available port and uses that port number. If the named instance is the only instance of the Database Engine installed, it will probably use TCP port 1433. If other instances of the Database Engine are installed, it will probably use a different TCP port. Because the port selected might change every time that the Database Engine is started, it is difficult to configure the firewall to enable access to the correct port number. Therefore, if a firewall is used, we recommend reconfiguring the Database Engine to use the same port number every time. This is called a fixed port or a static port. For more information, see Configure a Server to Listen on a Specific TCP Port (SQL Server Configuration Manager****

                    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 2.7.2, 24.11

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                    • M
                      malt0r
                      last edited by

                      Hi All,

                      I've found the error. It was a misconfiguration of the SQL Server. I've now configured the Instance to run on a fixed Port and now everything is working fine. Thanks for your great help  :)

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by

                        Glad got it sorted..  Curious why it worked on ipsec tunnel?  Unless you were connecting differently?

                        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 2.7.2, 24.11

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                        • M
                          malt0r
                          last edited by

                          Don't know why it is working on the IPSec Tunnel but I was connecting the same way than via OpenVPN. Doesn't matter iT#s working now and I'm happy with that  :)

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