SSH / Telnet Software

Telnet is an application layer protocol used on the Internet or local area networks to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. SSH was designed as a replacement for Telnet and for unsecured remote shell protocols. The term telnet is also used to refer to the software that implements the client part of the protocol. SSH provides a secure channel over an unsecured network in a client-server architecture, connecting an SSH client application with an SSH server.

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My company has setup an Ubuntu 18.04 server, to exchange files with a client, via SFTP.  We need a high level of security.  We're trying to require authentication with SSH key pairs, AND the Linux OS username and password (not the SSH passphrase). We've got the key pairs working, but it doesn't ask for the password. I'm assuming we're just missing something in the sshd_config file. Hopefully we're not trying to do something that's not possible. Any assistance would be much appreciated.

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Hi, when I finished installing OpenSSH, I got the following warning:

Permissions 0640 for '/etc/ssh/ssh_host_ecdsa_key' are too open.

Could you please give me the command line to safely change and set the proper permissions for this folder and its files?

Server: Red Hat Enterprise Linux Server 7.5


Jorge Batres
I removed the public SSH key from a server I was managing. THen I generated a new key and overwrote the old one on my laptop. THen I added the key to the server. it added two keys.

I thought it would be best practice to remove the old key and put the new one in. It seems like my old key is still being added to the server. Am I overthinking this?

Does it really not matter and should you not bother with changing SSH keys? I was going to change them by the business quarter.
Hi guys

I'm trying to set up an SFTP server for our company to use. I have a Windows 2012 server and have started to go down the open ssh route etc.

Do you guys have any guides one could follow or recommendations you would make?

If people think Linux would be a better route, then I can go down that route too. I need something that will be stable and not lose/drop connectivity because of some sort of service that needs restarting all of the time etc.

And I have to do this within the next 3hrs:).

Thanks for helping
Would someone have an explanation for this?

Both times I have run this script.

vmkfstools -i "/vmfs/volumes/Date-2016/00 - DNS Server/00 - DNS Server.vmdk" -d thin "/vmfs/volumes/DES Lessons/00-DNS-Serve
r/00 - DNS Server.vmdk"

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It gets to around 45%, and then jumps to 100%

Destination disk format: VMFS thin-provisioned
Cloning disk '/vmfs/volumes/Date-2016/00 - DNS Server/00 - DNS Server.vmdk'...
Clone: 100% done.

However, the actual size is 50GB
But the file transferred is only 16GB

00 - DNS Server.vmdk
16.53 GB
Sunday, May 20, 2018, 12:48:59 -0400

This is the actual size

00 - DNS Server.vmdk
50 GB
Saturday, April 28, 2018, 08:23:53 -0400

I have 7 VMs that need to be moved to a new drive, and this is causing some major slowing down issues.
Any ideas?

Also, if using the vmkfstools GUI is a better route to go, that would complete this without this issue.
Then please, tell me how to use the GUI, as I cannot find any information on using it.

Hello All;

I have a 1TB drive of which has 11 VMs on it.
Taking up about 95% of the space.
I purchased some 500GB driver, I am in the process of moving the VMs over.

What I have done.
Using the datastore, I chose the VMs and I "Moved" them.
It is going to take a few days to move the ones I selected over, about 426GB.

#2: I tried the OpenSSH
Just to move one of the VMs over that is 60GB, will take over 24-hours.

Code for the SSH

[root@localhost:/vmfs/volumes/5b005dd5-2ce20e85-e704-001517fcd2e8] scp -r "00 - DNS Server" root@"00\\-\\DNS\\Server"

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How can I make this go faster?
It is only going from one drive to another drive, on the same server.

I have a Dell laptop (running Windows 10) where I'm hosting OpenSuSE Linux (Leap 42.3) in a virtual machine. Although I can ping the virtual machine, I haven't been able to connect to it using the SSH protocol. As far as I can tell, the secure shell demon is running on the Linux system. I've tried a couple of SSH Windows clients – specifically, SecureCRT and SecureFX. Additionally, I've tried running the SSH client from the Windows command prompt. I haven't seen any error messages. Instead, the connection simply times out.

Networking is not my forte, but I'm familiar with SSH. I've configured it on UNIX systems many times, but that was years ago. These days I'm doing so only on rare occasions. Consequently, there's usually some small detail that I overlook. Any assistance would be greatly appreciated!
Unable to access FTP server using local account created.  Ftp server is 2003 and not using IIS, but OpenSSH.
User seems to have all the permissions needed to access through WinSCP, but I keep getting the access denied message when attempting to connect.
I'm not sure whether or not I did not add this user somewhere with permissions, whereas I am not an avid FTP server administrator.
Any help would be appreciated.
how can I ssh to a linux box and copy the key to the destination in one command

someone showed me this once it is l or ssh-L or somelike that
how to use Haproxy to publish an internal SFTP server.
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i have sftp install in ubuntu 16.04 hwo to disabled user to has a ssh login. user has only sftp login not ssh login.
We have a partner that has a MySQL / Maria DB Master server.  We have a slave and want to replicate against their master.  Some want to use the builtin SSL replication and others want to tunnel via SSH.  Can anyone provide some recommendations or pros and cons of each.  Any security, maintenance issues to consider?  Also, I assume that since we would be replicating against their master, they would have to run with the ssh port listening, not our slave?  Thanks
Hey I am changing my SSH key.

How do I remove my old SSH key from my servers trusted keys.
Have a new 3650 configured from scratch, I'm trying to get ssh/radius authentication setup.  I went through a guide to setup on switch, I have several others that are working so i know the server is setup correctly, but when i try to use it on the switch, SSh works, and i can log in with local creds, but AD creds don't work. Thinking I'm missing something.  was hoping someone could take a look over my config and see if anything stands out.. Thanks
i install ssh in ubuntu. i start services and it's  runnig. idisabled firewall. i add keygen in authorized_keys.
ssh <ip_host> says  Permission denied (publickey).
Hi There,

I had connected to Ubuntu machine in windows through putty's ssh client assume the IP address is

I want to clone bit bucket inside this putty

assume the bit bucket url


assume bit bucket user name is bharath and password is welcome

how to clone this bitbucket inside this putty

please help,  thanks in advance

Kind regards,

Bharath K
I'm trying to follow this guide in order to setup an SSH tunnel for VNC onto an ubuntu desktop from a Windows desktop.

I can connect via SSH but the moment I start the VNC connection to localhost::5902 I immediately get the following message:

"Connection has been gracefully closed".

Any ideas what could be causing this? Is it a bad setting on the Ubuntu computer I'm trying to VNC into? Did I configure PuTTY or TightVNC wrong? Is it because I changed the default SSH port number? Is there something I need to do on my router other than port forward the ssh connection appropriately (which I already did)? Is there an alternate method you would suggest?

Ubuntu 16.04 LTS & Windows 10, both 64 bit.
I am not familiar with Linux but have configured a Linux appliance. The box is configured and I can log into it via console. I never use putty and tried to SSH into but get the following below. I know am able to authenticate via console, but not SSH. I was wondering if I need to enable something to allow remote access.  If so, what commands must I put in to enable it? Please advise.

I have 1000+ of these - and it appears the parent process for each I have checked is the same command... not sure what is going on... any ideas?

8012     32605  0.0  0.0 110016  1264 ?        S    01:21   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32610  0.0  0.0 110016  1268 ?        S    01:22   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32611  0.0  0.0 110016  1268 ?        S    01:21   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32617  0.0  0.0 110016  1272 ?        S    01:21   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32618  0.0  0.0 110016  1264 ?        S    01:22   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32623  0.0  0.0 110016  1268 ?        S    01:21   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32625  0.0  0.0 110016  1268 ?        S    01:22   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32629  0.0  0.0 110016  1268 ?        S    01:21   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32632  0.0  0.0 110016  1268 ?        S    01:22   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32635  0.0  0.0 110016  1268 ?        S    01:21   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32639  0.0  0.0 110016  1272 ?        S    01:22   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32641  0.0  0.0 110016  1268 ?        S    01:21   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32646  0.0  0.0 110016  1272 ?        S    01:22   0:00 /bin/csh test -d /usr/lib64/qt-3.3
8012     32647  0.0  0.0 110016  1268 ?     

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Dear Experts,
I have spent so much time trying X11 forwarding but still no success. Can you help me with it?

I have the sudo privilege and my system is Ubuntu 17.10. I try the instruction like
But not work. here is my error

hsu@hcavfb11:~$ xclock
Error: Can't open display:

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We have an SFTP setup and have a client that wants to know what protocols/hashing algos/encryption we allow.  I found this info, I'm not sure if this is good... should any of these be disabled?  Any insight would be helpful.


[root@clientsftp ~]# ssh -Q cipher
[root@clientsftp ~]# ssh -Q mac
[root@clientsftp ~]# ssh -Q kex

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How can I tell if SSH and cypto key is enabled on cisco when I do show run ?
I have tunneled mixed linux and windows clients to a 'within-firewall client' (that could access the share's host) before, so I know that that, at least, is possible.

But what about tunneling directly from the client to the host of the network share?

Can I have samba listen on port, say, 5559 (just an example), and only accept connections from localhost, and tunnel a client's 5559 to that host - so that the client appears to be connecting from host's localhost? I can't figure out how to set it up. So far, I have samba configured:

hosts allow = ::1 lo
interfaces = lo
bind interfaces only = yes
And I'm tunneling from the host:

ssh -R 5559:localhost:5559 shrusr@shrhost -Nf
However, if samba is already running, than TCP forwarding fails. If the tunnel is already running, than samba cannot start. Is what I'm trying to accomplish possible? Is there some other way to do it?

It seems like it should work - I can even netcat myself files across that ssh tunnel. So, netcat has no problem listening to the same port as ssh. Only smbd refuses, and also blocks ssh from that port if started first.

Any advice would be appreciated.

I am currently researching techniques used to exfiltrate data, such as ICMP tunneling, SSH tunneling and DNS tunneling. I have come across the word "covert channels" but am not sure if this refers to the tunneling techniques I have mentioned. Can someone explain what the exfiltration techniques through tunneling are called? i am asking to try narrow down my research keywords. Not sure if they fall under covert channels.

Thanks in advance for your assistance
Python Script will not run because sshtunnel import to Python 3 does not seem import properly to the Pi.
I am thinking we are using the wrong version of ssh module python script for the Pi but I am struggling.  

 Hardware :
Raspberry Pi 3 Model B -  V 1.2  2015

OS Software :
pi@raspberrypi:~ $ cat /etc/*-release
PRETTY_NAME="Raspbian GNU/Linux 8 (jessie)"
NAME="Raspbian GNU/Linux"
VERSION="8 (jessie)"

import sshtunnel #import SSHTunnelForwarder
import mysql.connector

ID_String_Last = ["0"]

sshtunnel.SSH_TIMEOUT = 5.0
sshtunnel.TUNNEL_TIMEOUT = 5.0

with sshtunnel.SSHTunnelForwarder(
    ('**********this is the host in here **********'),
    ssh_username='', ssh_password='**********************',
    remote_bind_address=(',', 3306)
) as tunnel:
    connection = mysql.connector.connect(
        user='*********username**********', password='*****************',
        host='', port=tunnel.local_bind_port,

Python 3.4.2 (/usr/bin/python3)
>>> %Run '17-10- 15 V6.1 Pi mySQL to Ash'
Traceback (most recent call last):
  File "/home/pi/Desktop/17-10- 15 V6.1 Pi mySQL to Ash", line 3, in <module>
    import sshtunnel #import SSHTunnelForwarder
ImportError: No module named 'sshtunnel'

Does anybody know what version of module is required for this platform so that it …

SSH / Telnet Software

Telnet is an application layer protocol used on the Internet or local area networks to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. SSH was designed as a replacement for Telnet and for unsecured remote shell protocols. The term telnet is also used to refer to the software that implements the client part of the protocol. SSH provides a secure channel over an unsecured network in a client-server architecture, connecting an SSH client application with an SSH server.

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SSH / Telnet Software