Secure Shell (SSH) is a protocol primarily for encrypted shell connections.

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No TTY present when running commands over SSH in here-document

I'm trying to run a command over SSH like this in a here-document: ssh example.com <<END sudo /etc/init.d/apache2 reload END Which normally works except when I'm trying to run something that ...
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Yum install php-pecl-memcached - No package found (Have epel-release-6-8.noarch.rpm)

I believed I've downloaded and updated the EPEL rpm but I can't install php-pecl-memcached.. I'm very new to this, any help is appreciated. #rpm -Uvh epel-release-6-8.noarch.rpm warning: ...
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root locked out of EC2

I was in the process of disabling root logins on an AWS EC2 instance. Right after setting PermitRootLogin no and restarting sshd, I closed the terminal on accident -- before setting up users with sudo ...
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3answers
279 views

Block interactive SSH sessions while allowing certain commands

How would one only allow certain commands to be run via SSH and block interactive sessions? rsync.net does this as well as bakop.com. I.e. this would work: ssh <user@host> mkdir test scp ...
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3answers
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What's best practice for communication between Amazon EC2 instances?

I've been setting up Amazon EC2 instances for an upcoming project. They are all micro instances, running Ubuntu Server 64bit. Here's what I've setup so far: Web Server -- Apache Database Server ...
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Centralized management system for SSH keys?

We are looking to switch to key-based management of SSH logins, and wonder if there any key-management systems which would allow us to centrally manage the access keys world-wide. The system should ...
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4answers
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Can I automatically add a new host to known_hosts?

Here's my situation; I'm setting up a test harness that will, from a central client, launch a number of virtual machine instances and then execute commands on them via SSH. The virtual machines will ...
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6answers
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How do I run a local bash script on remote machines via ssh?

I am looking for a way to push configuration from one central machine to several remote machines without the need to install anything on the remote machines. The aim is to do something like you ...
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5answers
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Using SSH to remotely start a process

I have written a script that I am using to push and deploy a new service to several machines under my control, and in order to execute the process I am using ssh to remotely start the process. ...
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16answers
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Why Block Port 22 Outbound?

I'm a programmer, and I have worked for a few clients whose networks block outgoing connections on port 22. Considering that programmers often need to use port 22 for ssh, this seems like a ...
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2answers
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How to setup ssh tunnel to forward ssh?

I have computer with Ubuntu behind router that I can't configure. However I want to have ssh access to that computer. I think it is possible with ssh tunneling, but I don't know how to do it. I have ...
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SSH server zero-day exploit - Suggestions to protect ourselves

According to the Internet Storm Center, there seems to be a SSH zero-day exploit out there. There is some proof of concept code in here and some reference: ...
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“Virtual hosts” for SSH

We have a remote Xen server running a lot of guest machines (on Linux), with only a couple of IPs available. Each guest machine should be directly accessible by the SSH from the outer world. Right ...
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BASH shell session logging on remote host

What's the best method of logging a BASH shell session to a file on the host machine? The preferred output format would be equivalent to PuTTY's "printable output" log setting, as viewed by the user ...
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2answers
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How do I setup ssh with both private key and password?

How do I setup ssh with both private key and password? In /etc/ssh/sshd_config, I currently have: RSAAuthentication yes PubkeyAuthentication yes PasswordAuthentication yes But apparently this ...
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5answers
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How to remove strict RSA key checking in SSH and what's the problem here?

I have a Linux server that whenever I connect it shows me the message that changed the SSH host key: $ ssh root@host1 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: ...
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6answers
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Is there a name based virtual host SSH reverse proxy?

I've grown quite fond of HTTP reverse proxies in our development environment and found the DNS based virtual host reverse proxy quite useful. Having only one port (and the standard one) open on the ...
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5answers
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Disable usage of console-kit-daemon in Ubuntu

I administrate several Ubuntu 9.04 servers, and everytime I log in, I get the Landscape utility printout with server stats, etc. I really don't need this and it slows down my logins considerably. ...
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Does disabling root login enhance security?

I have recently found an argument against disabling a root user login in Linux at http://archives.neohapsis.com/archives/openbsd/2005-03/2878.html I assume that, if everybody uses a public key ...
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Connect through SSH and type in password automatically, without using a public key

A server allows SSH connections, but not using public key authentication. It's not within my power to change this at the moment (due to technical difficulties, not organizational) but I will get on it ...
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1answer
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Authenticate Linux sshd with TACACS+ (Cisco ACS)

Our network engineering team uses multiple linux servers for syslog collection, configuration backups, tftp, etc... We want to use TACACS+ on a Cisco ACS machine as our central authentication server ...
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4answers
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Reverse SSH tunnel: how can I send my port number to the server?

I have two machines, Client and Server. Client (who is behind a corporate firewall) opens a reverse SSH tunnel to Server, which has a publicly-accessible IP address, using this command: ssh -nNT ...
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2answers
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ssh fails to execute remote command when run from cron bash script - works from CLI

I have a script, written in bash, which runs from cron. One of the first things it does is SSH to a remote host and retrieve a list of files in a directory. Everything works fine when run from the ...
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2answers
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Restrict SSH login from a specific user to a specific IP address

I'd like to restrict SSH logins for a specific FreeBSD user account to a specific IP address (they're automated rsync backups from one machine to another, no actual user should ever be logging in, ...
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5answers
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protocol version mismatch — is your shell clean?

When following the instructions to do rsync backups given here: http://troy.jdmz.net/rsync/index.html I get the error "protocol version mismatch -- is your shell clean?" I read somewhere that I ...
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Why shouldn't root be allowed to login via ssh?

why should root access be disabled for ssh? I always hear that's for security reasons. But I don't get it. What's different to login as non-root and then sudo su -? What's the preferred way to handle ...
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3answers
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SSH from A through B to C, using private key on B

I'm looking for a simple way to SSH from my local machine, A, through a proxy, B, to a destination host, C. The private key that goes with the public key on C is on B, and I can't put that key on my ...
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1answer
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How to shutdown a virtual machine on ESXi5 over an ssh terminal session?

How can I shutdown a virtual machine when I am on the commandline of an ESXi5 host over ssh? Sidenote: To enable scripts on other machines to login to the ESXi without password, add the public ...
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3answers
156 views

Copy a file from remote to local

I am trying to copy a file from 10.10.10.99:/home/shantanu/ to the localhost. The only problem is that I need to tunnel the connection through 10.10.10.98 Something like this does not work.... ssh ...
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3answers
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how to restrict ssh login to a specific ip or host

i want to restrict my ssh login only for one ip address so i modified the following file $ nano /etc/ssh/sshd_config and added this line (i.e. my ip ) hoping that it will work ListenAddress ...
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3answers
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Can a malicious user bypass a ssh authorized_keys forced command?

Using Linux and Openssh: A user can connect using ssh to a server on which his key is in the authorized_keys list. His public key is preceded by command="command..." which forces execution of a ...
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2answers
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Can I limit my SSH Tunneling Speed?

So, I'm kind of making sshusers for ssh tunneling to surf some content which is blocked by my country. But, I don't want somebody to slow down others internet speed , therefore I want to limit the ...
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2answers
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“Corrupted MAC on input. Packet Corrupt” on file transfer over SSH, SCP, and FTP on Linux Server

help on this would be great. Specs: LAMP server Linux OS - Debian 5.0.1 4x Intel(R) Xeon(TM) CPU 2.80GHz Important Packages: openssl - SSL security iptables - firewall to block all requests ...
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3answers
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SSH via 3rd Machine

Local Computer (Fedora) --SSH--> Server1 --SSH--> Server2 In some environments I work in, we have to use "jump boxes" where you ssh to one server in order to get to another server. Is ...
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4answers
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ssh_exchange_identification: Connection closed by remote host

Firstly, I know that this question has been asked a million times, and I have read everything I can find and still cannot fix the problem. i am encountering this issue when ssh'ing in from my mac to ...
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1answer
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Using Upstart to Manage AutoSSH Reverse Tunnel

I'm using upstart to manage a reverse SSH tunnel via autossh. When I do a "sudo start tunnel" the connection comes up just fine; however the command is not being automatically run when the networking ...
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2answers
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SSH through multiple hosts using ProxyCommand?

I have an entry in ~/.ssh/config on my computer at home that look like this: host foo bar ProxyCommand ssh -x -a -q gateway.example.com nc %h 22 where gateway.example.com is a server at work ...
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642 views

Sharing public key with ssh

Is it possible to somehow setup an ssh server that doesn't require a username,password or cert to login? If that's not possible, if I were to give all customers the same public key, would each ...
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Docs for OpenSSH CA-based certificate based authentication

OpenSSH 5.4 added a new method for certificate authentication (changes). * Add support for certificate authentication of users and hosts using a new, minimal OpenSSH certificate format (not ...
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3answers
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ssh_exchange_identification: Connection closed by remote host

I failed in ssh connection to a server. Here is the output of connection $ ssh -v [server] OpenSSH_5.1p1 Debian-3ubuntu1, OpenSSL 0.9.8g 19 Oct 2007 debug1: Reading configuration data ...
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2answers
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rsync with script supplied password

I need to have a script periodically rsync files from a remote host via ssh. The account which the script runs under does not have home directory on the remote host, so I'm not able to store my ...
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2answers
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SSH/SFTP connections fails silently on OSX 10.8.2 - ssh-agent issue

I'm trying to login to a remote machine with SSH or SFTP. when I try ssh u-indgo@ssh1.eu1.frbit.com the CLI just won't respond. I get an empty new line, in which I can type characters, but nothing ...
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4answers
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Why does the $PATH of an ssh remote command differ from that of an interactive shell?

I have a user that has made no modifications to the $PATH in any dot-files: it is exactly the system default setting. From a login shell: $ ssh example.com user@example.com:~$ cat /tmp/hello.hs ...
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3answers
843 views

Changing Timezone, Centos Apache server

I'm trying to change my server's timezone. I was following this tutorial but I can't get it to change to Pacific Standard Time. ln -sf /usr/share/zoneinfo/EST localtime Will work, but ln -sf ...
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2answers
267 views

Re-gaining root access to an EC2 EBS-boot image

I'm using an Alestic image which disables root SSH logins, but provides a user "ubuntu" with NOPASSWD sudo privileges. See here. In the course of trying to add a new user to the sudoers file I ...
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root login via SSH still enabled after setting PermitRootLogin to 'no'

I'm trying to remove root access and password authentication over SSH to a RHEL server so that all users must access it using keys. So far the key access is set up and working, but I am unable to turn ...
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2answers
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SSH Connection Silently Dies

As the title says I'm having a very strange problem with SSH connections at my house, it seems that after about 3-5 minutes of inactivity any SSH sessions I have open will just shutdown and leave the ...
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1answer
344 views

Cannot connect to ec2 instance

I've created a new ec2 instance based on the php cloudformatino image ami-6fc2f61b and attached my existing key to it. Security group allows ssh and http. Yet, I'm unable to connect: $ ssh -v -i ...
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3answers
625 views

SSH connection keeps crashing

although this is not a real programming question perhaps anyone has any idea regarding my problem. It's pretty weird. When I remotely connect one of our ubuntu servers per ssh the connection can be ...
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1answer
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SSH directly “through” another server [duplicate]

Possible Duplicate: How to configure a shortcut for an SSH connection through a SSH tunnel Multiple networks I can connect to have the following set up. There is a single node that can be ...