saída estranha no tunelamento ssh: saída falhou; falha na conexão: o tempo limite da conexão expirou;

Eu uso o ssh user@xx.yy.zz.41 -p 1234 -D 9898comando para tunelamento e defino o firefox socks5 ip como 127.0.0.1 e sua porta como 9898. Funciona com êxito, mas no terminal tenho erro na saída:

channel 39: open failed: connect failed: Connection timed out
channel 41: open failed: connect failed: Connection timed out
channel 42: open failed: connect failed: Connection timed out
channel 43: open failed: connect failed: Connection timed out
channel 44: open failed: connect failed: Connection timed out

Isso ocorre periodicamente. O que é isso? Isso é um problema? O que eu posso fazer?

Eu tive problemas semelhantes. Se você estiver encapsulando o Firefox através do ssh, algumas conexões http podem simplesmente atingir o tempo limite devido à carga do servidor ou a uma configuração incorreta. Quando a conexão realmente atingir o tempo limite, você receberá uma mensagem de erro como a que você indicou.

Você pode suprimir essas mensagens com o seguinte comando

ssh user@xx.yy.zz.41 -p 1234 -D 9898 -q

Na página do manual ssh(1)

 -q      Quiet mode.  Causes most warning and diagnostic messages to be sup-
         pressed.

Suprimir a mensagem impedirá que os avisos atrapalhem suas sessões de ssh ou tela.

Defina o GatewayPortspara yese tente novamente.

ssh -o 'GatewayPorts yes' user@xx.yy.zz.41 -p 1234 -D 9898

man ssh_config

 DynamicForward
         Specifies that a TCP port on the local machine be forwarded over the secure channel, and the application protocol
         is then used to determine where to connect to from the remote machine.

         The argument must be [bind_address:]port.  IPv6 addresses can be specified by enclosing addresses in square
         brackets.  By default, the local port is bound in accordance with the GatewayPorts setting.  However, an explicit
         bind_address may be used to bind the connection to a specific address.  The bind_address of “localhost” indicates
         that the listening port be bound for local use only, while an empty address or ‘*’ indicates that the port should
         be available from all interfaces.

         Currently the SOCKS4 and SOCKS5 protocols are supported, and ssh(1) will act as a SOCKS server.  Multiple for‐
         wardings may be specified, and additional forwardings can be given on the command line.  Only the superuser can
         forward privileged ports.

 GatewayPorts
         Specifies whether remote hosts are allowed to connect to local forwarded ports.  By default, ssh(1) binds local
         port forwardings to the loopback address.  This prevents other remote hosts from connecting to forwarded ports.
         GatewayPorts can be used to specify that ssh should bind local port forwardings to the wildcard address, thus
         allowing remote hosts to connect to forwarded ports.  The argument must be “yes” or “no”.  The default is “no”.