Windows 10 users facing issues with PuTTY’s SSH forwarding

While using Workbench, I attempted to connect to a certain port after successfully establishing an SSH connection through PuTTY. However, my attempt failed. It’s worth noting that my laptop (W10 Enterprise v1809) has the exact same setup, and it works perfectly fine. The configuration settings for both PuTTY and Workbench were exported from my laptop. To connect to the server, I created an SSH session on a specific port and forwarded a local port to the remote server’s port under SSH > Tunnels.

Question:

I’m attempting to configure PuTTY with
SSH tunnel
to establish a connection to a RHEL server’s database through
MySQL Workbench
via SSH.

  • I established an SSH session on port

    22

    to connect to the server. Then, I went to the SSH > Tunnels section and forwarded
    local port
    from

    49900

    on my computer to the remote server’s

    3306

    (

    L49900 remoteserverip:3306

    ). Later, I attempted to connect to

    localhost

    on port

    49900

    in Workbench after connecting through PuTTY over SSH, but the connection failed, resulting in the error message

    Unable to connect to 127.0.0.1:49900

    .

My laptop (W10 Enterprise v1809) has the same configuration as my desktop but works fine. I exported both PuTTY and Workbench configurations from my laptop. However, when I tried to replicate the process on my desktop (W10 Pro v1909), Workbench displayed an error with

Unable to connect to 127.0.0.1:49900

.

I attempted to test the port using Powershell on Windows 10, along with two additional servers. Unfortunately, none of them were functional, even when attempting to forward web ports.

  • Desktop:

    Test-NetConnection -ComputerName 127.0.0.1 -Port 49900
    WARNING: TCP connect to (127.0.0.1 : 49900) failed
    ComputerName           : 127.0.0.1
    RemoteAddress          : 127.0.0.1
    RemotePort             : 49900
    InterfaceAlias         : Loopback Pseudo-Interface 1
    SourceAddress          : 127.0.0.1
    PingSucceeded          : True
    PingReplyDetails (RTT) : 0 ms
    TcpTestSucceeded       : False
     
  • Laptop:

    Test-NetConnection -ComputerName 127.0.0.1 -Port 49900
    ComputerName           : 127.0.0.1
    RemoteAddress          : 127.0.0.1
    RemotePort             : 49900
    InterfaceAlias         : Loopback Pseudo-Interface 1
    SourceAddress          : 127.0.0.1
    PingSucceeded          : True
     

I have confirmed that my keys are accurate since I utilize

.ppk

on both of my machines. Consequently, I can access all of my servers from either device except for the forwarding function, which is malfunctioning only on my desktop machine.

  • PuTTY Log:

    • Desktop:

      Incoming packet 0x6, type 52 / 0x34 (SSH2_MSG_USERAUTH_SUCCESS)
      Event Log: Access granted 
      Event Log: Local port 49900 forwarding to [remoteip]:3306 failed: Network error: Permission denied
      
    • Laptop

      Incoming packet 0x7, type 52 / 0x34 (SSH2_MSG_USERAUTH_SUCCESS)
      Event Log: Access granted
      Event Log: Local port 49900 forwarding to [remoteip]:3306 
      Event Log: Opening main session channel Outgoing packet 0x8, type 90 / 0x5a (SSH2_MSG_CHANNEL_OPEN)
      
  • PuTTY Profile:

    [HKEY_CURRENT_USERSoftwareSimonTathamPuTTYSessionsBF%20login]
    "Present"=dword:00000001
    "HostName"="*****************"
    "LogFileName"="C:\putty.log"
    "LogType"=dword:00000004
    "LogFileClash"=dword:ffffffff
    "LogFlush"=dword:00000001
    "LogHeader"=dword:00000001
    "SSHLogOmitPasswords"=dword:00000001
    "SSHLogOmitData"=dword:00000000
    "Protocol"="ssh"
    "PortNumber"=dword:00000016
    "CloseOnExit"=dword:00000001
    "WarnOnClose"=dword:00000001
    "PingInterval"=dword:00000000
    "PingIntervalSecs"=dword:00000000
    "TCPNoDelay"=dword:00000001
    "TCPKeepalives"=dword:00000000
    "TerminalType"="xterm"
    "TerminalSpeed"="38400,38400"
    "TerminalModes"="CS7=A,CS8=A,DISCARD=A,DSUSP=A,ECHO=A,ECHOCTL=A,ECHOE=A,ECHOK=A,ECHOKE=A,ECHONL=A,EOF=A,EOL=A,EOL2=A,ERASE=A,FLUSH=A,ICANON=A,ICRNL=A,IEXTEN=A,IGNCR=A,IGNPAR=A,IMAXBEL=A,INLCR=A,INPCK=A,INTR=A,ISIG=A,ISTRIP=A,IUCLC=A,IUTF8=A,IXANY=A,IXOFF=A,IXON=A,KILL=A,LNEXT=A,NOFLSH=A,OCRNL=A,OLCUC=A,ONLCR=A,ONLRET=A,ONOCR=A,OPOST=A,PARENB=A,PARMRK=A,PARODD=A,PENDIN=A,QUIT=A,REPRINT=A,START=A,STATUS=A,STOP=A,SUSP=A,SWTCH=A,TOSTOP=A,WERASE=A,XCASE=A"
    "AddressFamily"=dword:00000000
    "ProxyExcludeList"=""
    "ProxyDNS"=dword:00000001
    "ProxyLocalhost"=dword:00000000
    "ProxyMethod"=dword:00000000
    "ProxyHost"="proxy"
    "ProxyPort"=dword:00000050
    "ProxyUsername"=""
    "ProxyPassword"=""
    "ProxyTelnetCommand"="connect %host %port\n"
    "ProxyLogToTerm"=dword:00000001
    "Environment"=""
    "UserName"=""
    "UserNameFromEnvironment"=dword:00000000
    "LocalUserName"=""
    "NoPTY"=dword:00000000
    "Compression"=dword:00000000
    "TryAgent"=dword:00000001
    "AgentFwd"=dword:00000000
    "GssapiFwd"=dword:00000000
    "ChangeUsername"=dword:00000000
    "Cipher"="aes,chacha20,3des,WARN,des,blowfish,arcfour"
    "KEX"="ecdh,dh-gex-sha1,dh-group14-sha1,rsa,WARN,dh-group1-sha1"
    "HostKey"="ed25519,ecdsa,rsa,dsa,WARN"
    "RekeyTime"=dword:0000003c
    "GssapiRekey"=dword:00000002
    "RekeyBytes"="1G"
    "SshNoAuth"=dword:00000000
    "SshBanner"=dword:00000001
    "AuthTIS"=dword:00000000
    "AuthKI"=dword:00000001
    "AuthGSSAPI"=dword:00000001
    "AuthGSSAPIKEX"=dword:00000001
    "GSSLibs"="gssapi32,sspi,custom"
    "GSSCustom"=""
    "SshNoShell"=dword:00000000
    "SshProt"=dword:00000003
    "LogHost"=""
    "SSH2DES"=dword:00000000
    "PublicKeyFile"=""
    "RemoteCommand"=""
    "RFCEnviron"=dword:00000000
    "PassiveTelnet"=dword:00000000
    "BackspaceIsDelete"=dword:00000001
    "RXVTHomeEnd"=dword:00000000
    "LinuxFunctionKeys"=dword:00000000
    "NoApplicationKeys"=dword:00000000
    "NoApplicationCursors"=dword:00000000
    "NoMouseReporting"=dword:00000000
    "NoRemoteResize"=dword:00000000
    "NoAltScreen"=dword:00000000
    "NoRemoteWinTitle"=dword:00000000
    "NoRemoteClearScroll"=dword:00000000
    "RemoteQTitleAction"=dword:00000001
    "NoDBackspace"=dword:00000000
    "NoRemoteCharset"=dword:00000000
    "ApplicationCursorKeys"=dword:00000000
    "ApplicationKeypad"=dword:00000000
    "NetHackKeypad"=dword:00000000
    "AltF4"=dword:00000001
    "AltSpace"=dword:00000000
    "AltOnly"=dword:00000000
    "ComposeKey"=dword:00000000
    "CtrlAltKeys"=dword:00000001
    "TelnetKey"=dword:00000000
    "TelnetRet"=dword:00000001
    "LocalEcho"=dword:00000002
    "LocalEdit"=dword:00000002
    "Answerback"="PuTTY"
    "AlwaysOnTop"=dword:00000000
    "FullScreenOnAltEnter"=dword:00000000
    "HideMousePtr"=dword:00000000
    "SunkenEdge"=dword:00000000
    "WindowBorder"=dword:00000001
    "CurType"=dword:00000000
    "BlinkCur"=dword:00000000
    "Beep"=dword:00000001
    "BeepInd"=dword:00000000
    "BellWaveFile"=""
    "BellOverload"=dword:00000001
    "BellOverloadN"=dword:00000005
    "BellOverloadT"=dword:000007d0
    "BellOverloadS"=dword:00001388
    "ScrollbackLines"=dword:000007d0
    "DECOriginMode"=dword:00000000
    "AutoWrapMode"=dword:00000001
    "LFImpliesCR"=dword:00000000
    "CRImpliesLF"=dword:00000000
    "DisableArabicShaping"=dword:00000000
    "DisableBidi"=dword:00000000
    "WinNameAlways"=dword:00000001
    "WinTitle"=""
    "TermWidth"=dword:00000050
    "TermHeight"=dword:00000018
    "Font"="Courier New"
    "FontIsBold"=dword:00000000
    "FontCharSet"=dword:00000000
    "FontHeight"=dword:0000000a
    "FontQuality"=dword:00000000
    "FontVTMode"=dword:00000004
    "UseSystemColours"=dword:00000000
    "TryPalette"=dword:00000000
    "ANSIColour"=dword:00000001
    "Xterm256Colour"=dword:00000001
    "TrueColour"=dword:00000001
    "BoldAsColour"=dword:00000001
    "Colour0"="187,187,187"
    "Colour1"="255,255,255"
    "Colour2"="0,0,0"
    "Colour3"="85,85,85"
    "Colour4"="0,0,0"
    "Colour5"="0,255,0"
    "Colour6"="0,0,0"
    "Colour7"="85,85,85"
    "Colour8"="187,0,0"
    "Colour9"="255,85,85"
    "Colour10"="0,187,0"
    "Colour11"="85,255,85"
    "Colour12"="187,187,0"
    "Colour13"="255,255,85"
    "Colour14"="0,0,187"
    "Colour15"="85,85,255"
    "Colour16"="187,0,187"
    "Colour17"="255,85,255"
    "Colour18"="0,187,187"
    "Colour19"="85,255,255"
    "Colour20"="187,187,187"
    "Colour21"="255,255,255"
    "RawCNP"=dword:00000000
    "UTF8linedraw"=dword:00000000
    "PasteRTF"=dword:00000000
    "MouseIsXterm"=dword:00000000
    "RectSelect"=dword:00000000
    "PasteControls"=dword:00000000
    "MouseOverride"=dword:00000001
    "Wordness0"="0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0"
    "Wordness32"="0,1,2,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,1,1,1,1,1,1"
    "Wordness64"="1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,1,1,1,2"
    "Wordness96"="1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,1,1,1,1"
    "Wordness128"="1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1"
    "Wordness160"="1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1"
    "Wordness192"="2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2"
    "Wordness224"="2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,2,2,2,2,2"
    "MouseAutocopy"=dword:00000001
    "MousePaste"="explicit"
    "CtrlShiftIns"="explicit"
    "CtrlShiftCV"="none"
    "LineCodePage"=""
    "CJKAmbigWide"=dword:00000000
    "UTF8Override"=dword:00000001
    "Printer"=""
    "CapsLockCyr"=dword:00000000
    "ScrollBar"=dword:00000001
    "ScrollBarFullScreen"=dword:00000000
    "ScrollOnKey"=dword:00000000
    "ScrollOnDisp"=dword:00000001
    "EraseToScrollback"=dword:00000001
    "LockSize"=dword:00000000
    "BCE"=dword:00000001
    "BlinkText"=dword:00000000
    "X11Forward"=dword:00000000
    "X11Display"=""
    "X11AuthType"=dword:00000001
    "X11AuthFile"=""
    "LocalPortAcceptAll"=dword:00000000
    "RemotePortAcceptAll"=dword:00000000
    "PortForwardings"="L49900=*********************:3306"
    "BugIgnore1"=dword:00000000
    "BugPlainPW1"=dword:00000000
    "BugRSA1"=dword:00000000
    "BugIgnore2"=dword:00000000
    "BugHMAC2"=dword:00000000
    "BugDeriveKey2"=dword:00000000
    "BugRSAPad2"=dword:00000000
    "BugPKSessID2"=dword:00000000
    "BugRekey2"=dword:00000000
    "BugMaxPkt2"=dword:00000000
    "BugOldGex2"=dword:00000000
    "BugWinadj"=dword:00000000
    "BugChanReq"=dword:00000000
    "StampUtmp"=dword:00000001
    "LoginShell"=dword:00000001
    "ScrollbarOnLeft"=dword:00000000
    "BoldFont"=""
    "BoldFontIsBold"=dword:00000000
    "BoldFontCharSet"=dword:00000000
    "BoldFontHeight"=dword:00000000
    "WideFont"=""
    "WideFontIsBold"=dword:00000000
    "WideFontCharSet"=dword:00000000
    "WideFontHeight"=dword:00000000
    "WideBoldFont"=""
    "WideBoldFontIsBold"=dword:00000000
    "WideBoldFontCharSet"=dword:00000000
    "WideBoldFontHeight"=dword:00000000
    "ShadowBold"=dword:00000000
    "ShadowBoldOffset"=dword:00000001
    "SerialLine"="COM1"
    "SerialSpeed"=dword:00002580
    "SerialDataBits"=dword:00000008
    "SerialStopHalfbits"=dword:00000002
    "SerialParity"=dword:00000000
    "SerialFlowControl"=dword:00000001
    "WindowClass"=""
    "ConnectionSharing"=dword:00000000
    "ConnectionSharingUpstream"=dword:00000001
    "ConnectionSharingDownstream"=dword:00000001
    "SSHManualHostKeys"=""
     



Solution 1:

The TCP port 49900 falls under the dynamic port range, also known as
port range
, which ranges from 49152 to 65535 and is reserved for this purpose.

It is not advisable to utilize ports within that particular range for opening services. Instead, it is recommended to use a port range starting from 1024 up to
49151
.


Solution 2:


The issue was resolved by switching the local port to a lower number (3307), although it remains unclear why it functions on the laptop but not on the desktop with port 49900.

Frequently Asked Questions