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    X11 forwarding request failed on channel 0 after 2.5.0

    Scheduled Pinned Locked Moved General pfSense Questions
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @chudak
      last edited by

      What are you using to ssh (what is your client? putty, securecrt, ssh)

      I don't see such an error - I ssh into pfsense pretty much every day..

      ssh.png

      I even enable x11 forwarding - and still don't see such an error

      forward.png

      An intelligent man is sometimes forced to be drunk to spend time with his fools
      If you get confused: Listen to the Music Play
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      chudakC 1 Reply Last reply Reply Quote 0
      • chudakC
        chudak @johnpoz
        last edited by

        @johnpoz

        I ssh from ubuntu with term or terminator and never saw it before 2.5.0

        I don't use putty but tried it and don't see this error

        1 Reply Last reply Reply Quote 0
        • bingo600B
          bingo600
          last edited by

          @chudak said in X11 forwarding request failed on channel 0 after 2.5.0:

          X11 forwarding request failed on channel 0

          Have a look here
          https://www.linuxsecrets.com/1204-how-to-fix-x11-forwarding-request-failed-on-channel-0
          https://stackoverflow.com/questions/38961495/x11-forwarding-request-failed-on-channel-0

          According to the above it could be localhost or ipv6 related

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          • chudakC
            chudak @bingo600
            last edited by

            @bingo600 thx !

            The question is - why is it popping up after 2.5.0 and never before ?

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

              While it might be popping up for you - its not popping up here.. I have been unable to even get it to pop up even using ssh with -X

              do a ssh -x, do you still get it? What is your client settings specifically?

              Do a verbose connection -v so you see some details..

              For example I can see this when do -Xv

              debug1: Remote: /root/.ssh/authorized_keys:1: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
              debug1: Remote: /root/.ssh/authorized_keys:1: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding
              debug1: X11 forwarding requested but DISPLAY not set
              

              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
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              chudakC 1 Reply Last reply Reply Quote 0
              • chudakC
                chudak @johnpoz
                last edited by

                @johnpoz

                I don't see the error with ssh -x, nothing special about ssh client settings AFAIK

                See verbose here https://pastebin.com/hTDiEfJz

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

                  Not seeing the rest of this - it stops where your having to auth with password. What is the rest after you auth.

                  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
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                  chudakC 1 Reply Last reply Reply Quote 0
                  • chudakC
                    chudak @johnpoz
                    last edited by chudak

                    @johnpoz

                    sorry missed that

                    debug1: Authentication succeeded (keyboard-interactive).
                    Authenticated to pfsense ([192.168.0.1]:22).
                    debug1: channel 0: new [client-session]
                    debug1: Requesting no-more-sessions@openssh.com
                    debug1: Entering interactive session.
                    debug1: pledge: exec
                    debug1: client_input_global_request: rtype hostkeys-00@openssh.com want_reply 0
                    debug1: Requesting X11 forwarding with authentication spoofing.
                    debug1: Sending environment.
                    debug1: Sending env LANG = en_US.UTF-8
                    X11 forwarding request failed on channel 0
                    pfSense - Netgate Device ID:xyz
                    
                    johnpozJ 1 Reply Last reply Reply Quote 0
                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator @chudak
                      last edited by

                      What is your local clients that your sshing from config

                      Should be on your client in /etc/ssh/ssh_config

                      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

                      chudakC 1 Reply Last reply Reply Quote 0
                      • chudakC
                        chudak @johnpoz
                        last edited by

                        @johnpoz said in X11 forwarding request failed on channel 0 after 2.5.0:

                        /etc/ssh/ssh_conf

                        cat /etc/ssh/ssh_config
                        
                        # This is the ssh client system-wide configuration file.  See
                        # ssh_config(5) for more information.  This file provides defaults for
                        # users, and the values can be changed in per-user configuration files
                        # or on the command line.
                        
                        # Configuration data is parsed as follows:
                        #  1. command line options
                        #  2. user-specific file
                        #  3. system-wide file
                        # Any configuration value is only changed the first time it is set.
                        # Thus, host-specific definitions should be at the beginning of the
                        # configuration file, and defaults at the end.
                        
                        # Site-wide defaults for some commonly used options.  For a comprehensive
                        # list of available options, their meanings and defaults, please see the
                        # ssh_config(5) man page.
                        
                        Include /etc/ssh/ssh_config.d/*.conf
                        
                        Host *
                        #   ForwardAgent no
                           ForwardX11 yes
                           ForwardX11Trusted yes
                        #   PasswordAuthentication yes
                        #   HostbasedAuthentication no
                        #   GSSAPIAuthentication no
                        #   GSSAPIDelegateCredentials no
                        #   GSSAPIKeyExchange no
                        #   GSSAPITrustDNS no
                        #   BatchMode no
                        #   CheckHostIP yes
                        #   AddressFamily any
                        #   ConnectTimeout 0
                        #   StrictHostKeyChecking ask
                        #   IdentityFile ~/.ssh/id_rsa
                        #   IdentityFile ~/.ssh/id_dsa
                        #   IdentityFile ~/.ssh/id_ecdsa
                        #   IdentityFile ~/.ssh/id_ed25519
                        #   Port 22
                        #   Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc
                        #   MACs hmac-md5,hmac-sha1,umac-64@openssh.com
                        #   EscapeChar ~
                        #   Tunnel no
                        #   TunnelDevice any:any
                        #   PermitLocalCommand no
                        #   VisualHostKey no
                        #   ProxyCommand ssh -q -W %h:%p gateway.example.com
                        #   RekeyLimit 1G 1h
                            SendEnv LANG LC_*
                            HashKnownHosts yes
                            GSSAPIAuthentication yes
                        
                        johnpozJ 1 Reply Last reply Reply Quote 0
                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @chudak
                          last edited by

                          @chudak said in X11 forwarding request failed on channel 0 after 2.5.0:

                          ForwardX11 yes
                          ForwardX11Trusted yes

                          Comment those out, or set to no and your error will go away ;)

                          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

                          chudakC 1 Reply Last reply Reply Quote 0
                          • chudakC
                            chudak @johnpoz
                            last edited by

                            @johnpoz said in X11 forwarding request failed on channel 0 after 2.5.0:

                            @chudak said in X11 forwarding request failed on channel 0 after 2.5.0:

                            ForwardX11 yes
                            ForwardX11Trusted yes

                            Comment those out, or set to no and your error will go away ;)

                            My fault after all :( has nothing to do with 2.5.0 !

                            Thx @johnpoz
                            But it's good to be sure :)

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

                              Did you change something there between going to 2.5? I don't think that is default on ssh install to enable that..

                              But if your using some gui term or package in your OS, maybe it set that?

                              But you mentioned you don't use X11 forwarding, and not sure how you would do X11 to pfsense anyway ;) But yeah can understand why you would want the error not to be there ;)

                              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

                              chudakC 1 Reply Last reply Reply Quote 0
                              • chudakC
                                chudak @johnpoz
                                last edited by chudak

                                @johnpoz said in X11 forwarding request failed on channel 0 after 2.5.0:

                                Did you change something there between going to 2.5? I don't think that is default on ssh install to enable that..

                                But if your using some gui term or package in your OS, maybe it set that?

                                But you mentioned you don't use X11 forwarding, and not sure how you would do X11 to pfsense anyway ;) But yeah can understand why you would want the error not to be there ;)

                                Hard to say if I did change anything, but as long as it's not 2.5.0 I am happy :)

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                                • jimpJ
                                  jimp Rebel Alliance Developer Netgate
                                  last edited by

                                  I don't recall exactly when, I thought it was in 2.4.x, but we disabled X11 forwarding in the SSH daemon on the firewall for security reasons.

                                  The error is harmless though, you can ignore it, or like you've done, disable it on the client side.

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