====== SSH não conecta em servidores Linux ======

Estou tentando a partir de um roteador cisco fazer uma conexão SSH em um servidor Linux e recebo a seguinte mensagem:

<code bash>
hercules#ssh -l alguem 192.168.1.8

[Connection to 192.168.1.8 aborted: error status 0]
hercules#
</code> 

Visualizando os logs do roteador

<code bash>
hercules#sh loggi                     
Syslog logging: enabled (0 messages dropped, 3 messages rate-limited, 0 flushes, 0 overruns, xml disabled, filtering disabled)

No Active Message Discriminator.



No Inactive Message Discriminator.


    Console logging: level debugging, 15365 messages logged, xml disabled,
                     filtering disabled
    Monitor logging: level debugging, 0 messages logged, xml disabled,
                     filtering disabled
    Buffer logging:  level warnings, 15320 messages logged, xml disabled,
                    filtering disabled
    Exception Logging: size (4096 bytes)
    Count and timestamp logging messages: disabled
    Persistent logging: disabled

No active filter modules.

    Trap logging: level informational, 15368 message lines logged
          
Log Buffer (51200 bytes):

015365: *Jul 31 22:23:27.573: %SSH-3-NO_MATCH: No matching cipher found: client aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc server chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
hercules#
</code>

Foi gerado um erro de não encontrar a cifra de criptografia no servidor Linux. Então vamos adicionar a cifra dentro do arquivo **/etc/ssh/sshd_config**

<code autoconf>
Ciphers +aes256-ctr,aes192-ctr,aes128-ctr,rijndael-cbc@lysator.liu.se,aes256-cbc,aes192-cbc,aes128-cbc,arcfour256,arcfour128,arcfour,cast128-cbc,blowfish-cbc,3des-cbc
</code>

e depois reiniciar o servidor ssh

<code bash>
root@megatron:~# /etc/init.d/ssh restart
[ ok ] Restarting ssh (via systemctl): ssh.service.
root@megatron:~# 
</code>

Tentar o acesso novamente.

<code bash>
hercules#ssh -l alguem 192.168.1.8

Password: 
Welcome to Ubuntu 16.04.1 LTS (GNU/Linux 4.4.0-130-generic x86_64)

 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/advantage


Last login: Tue Jul 31 18:01:26 2018 from 192.168.1.95
alguem@megatron:~$ 
</code>