Questions about the OpenSSH implementation of the ssh protocol.

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0
votes
1answer
281 views

SSH to Linux Container from Other Machine

I am trying to learn about Linux Containers and this is my first encounter with servers, ssh and many other things that I do not know the terms yet. I create five different containers and authorized ...
-1
votes
1answer
371 views

Double port forwarding - SSH

NOTE: I'm not explaining why I want to do this. But here is the requirement. There are 4 hosts. Host A, Host B, Host C, Host D Host A is running some application which can be accessed at port 8001 ...
5
votes
2answers
137 views

Why are rules not combining in an ssh config file?

It seems like the following would work as expected, i.e., that the second rule, having a hostname that matches the first rule, would apply it. Host *.hostname.com User myuser IdentityFile ...
1
vote
1answer
468 views

Setting the bash SHELL for remote openSSH connections?

I am connected to a Freebsd 10 -STABLE server with SSH from my office box but when I trying to work inside the session I encounter these problems: although I did chsh for every user in said server ...
0
votes
1answer
102 views

Linux Fedora Core 18 freezes on OpenSSH login

miagos:~ $ uname -a Linux miagos 3.9.6-200.fc18.x86_64 #1 SMP Thu Jun 13 18:56:55 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux I have a reproducible issue, when my desktop Linux node stays online for more ...
1
vote
3answers
13k views

Where are my sshd logs?

I can't find my sshd logs in the standard places. What I've tried: Not in /var/log/auth.log Not in /var/log/secure Did a system search for 'auth.log' and found nothing I've set /etc/ssh/sshd_config ...
4
votes
2answers
173 views

SSH - How to make X applications run on client?

I have the reverse problem that most people seem to be having. If I start an X application while logged into ssh, it displays on the server(host) machine instead of the client(local). This is the ...
0
votes
1answer
59 views

Supply additional ssh options in config file

How can I supply additional options in .ssh/config? I know that information like Host, Port, User etc. may be used in the ssh-configuration file to abbreviate ssh commands. I frequently create ...
0
votes
0answers
1k views

OpenSSH hangs after login without showing login prompt

I ran across an issue with ssh after fresh Ubuntu 13.10 installation on Lenovo T420. I tried git pull (which failed) and this led me to more general ssh failing. After spending some 2-3 hrs of ...
1
vote
1answer
1k views

ssh_exchange_identification: Connection closed by remote host on vnx machine (linux)

I changed the password of my linux machine . I was able to login for sometime and after that I am not able to ssh. I am getting the following error: ssh es4042cs -v OpenSSH_5.1p1, OpenSSL ...
3
votes
1answer
478 views

Disable ForwardX11Timeout without ForwardX11Trusted in OpenSSH Client?

By default, recent versions of OpenSSH automatically set ForwardX11Timeout to 20 minutes if you set ForwardX11Trusted to no. This means that 20 minutes after you start your ssh connection, you can't ...
3
votes
2answers
752 views

SSH access from inside and outside a LAN using the same terminal command

I have a Raspberry Pi (RPi) and I am making remote connections to it using ssh. I have managed to set up ssh correctly such that I can access the RPi both from a local area network and from the ...
0
votes
0answers
250 views

How can I get ssh working on Mint Olivia?

I have a Mint KDE VM (under VMware Fusion on Mavericks), and it is refusing ssh connections. I have not enabled UFW, and openssh-server installed without reported error. However, when I attempt to ...
2
votes
3answers
2k views

Trying to SSH into my Android phone, but connection closed

I am trying to use the ssh/sftp Daemon app on Android, and SSHing into the phone using an openssh client. Here is the verbose output I get right before the connection breaks debug1: Authentication ...
1
vote
1answer
268 views

Session limit for OpenSSH server on Ubuntu Desktop 7.10

I need restrict session limit on my OpenSSH server only for one session (one connection). I use Ubuntu Desktop 7.10. Of course Version is old, but I need it for experimental purposes. I tried modify ...
1
vote
3answers
199 views

Can't ssh to a machine

All of a sudden, I couldn't ssh to a machine to which I used to ssh earlier. Consider I am ssh-ing from A to B. Output when I run ssh root@ip_addr_of_B I get: Permission denied ...
4
votes
1answer
1k views

sFTP server fails to start

I'm having problems getting sFTP working while there are no problems with ssh. I'm basically building zlib, openssl, and openssh for an ARM processor using an existing embedded Linux filesystem. After ...
6
votes
2answers
726 views

Why not simply use %h in OpenSSH ssh's ControlPath option?

Why do the "ssh_config(5)" manpages recommend that the ControlPath option should contain at least the %h, %p and %r placeholders in order to uniquely identify each shared connection? I thought that ...
7
votes
2answers
10k views

What do the channel numbers in ssh error message refer to?

In the example below what do the channel numbers correspond to? Which are on the server? Which are on the client? $ ssh -L1570:127.0.0.1:8899 root@thehost Password: Last login: Fri Aug 9 ...
12
votes
1answer
7k views

Convert OpenSSH private key into SSH2 private key

Is there a way to convert existing pair of OpenSSH keys to the SSH2 (ssh.com format) pair of keys? UPD: since there are some answers about ssh-keygen suddenly appeared, I'll explain where I came ...
3
votes
2answers
406 views

how does ssh discover hostnames on the network?

We have a server on the company network named serverA, and if I type ssh serverA, it will connect my PC to this server, even though there is no entry for this server in my /etc/hosts, but I used to ...
1
vote
2answers
254 views

Unable to force passphraseless ssh authentication while port forwarding

I'm completely at a loss as to what is preventing my local machine from authenticating the connection that is being forwarded from the remote server. I've read a ton of the posts on here regarding ...
3
votes
1answer
80 views

What are all of the SSH Key files?

There are six key files in /etc/ssh directory for private and public keys. 4 of them are for DSA and RSA public & private keys. but there are two more files named ssh_host_key and ...
1
vote
1answer
182 views

How to prevent ssh-agent from starting in CentOS?

How do I stop ssh-agent from starting when logging into CentOS via openssh? There are no references to ssh-agent in my bash startup scripts (.bashrc) or /etc/bashrc.
3
votes
2answers
253 views

Why doesn't the ssh command follow RFC on URI?

The RFC: Uniform Resource Identifier (URI) Scheme for Secure File Transfer Protocol (SFTP) and Secure Shell (SSH) presents the SSH URI as: ssh://[<user>[;fingerprint=<host-key ...
5
votes
1answer
114 views

Can an OpenSSH server forward inbound traffic to another server?

In my current work setup, I have: Windows 7 laptop Ubuntu virtual host / SSH Windows 2k8 guest I'd like to be able to RDP from my laptop into the Windows guest without having to open additional ...
13
votes
2answers
9k views

What difference between openssh key and putty key?

I've found ssh-keygen ("ssh" package) comand produce another keys that puttygen command ("putty" package). If I create public and private keys with ssh-keygen some ssh-servers can not accept my keys. ...
2
votes
1answer
448 views

ssh-add -D doesn't erase stored keys from the ssh-agent

How come this happens?: stan@tcpc:~/.ssh$ ssh-add -l 8192 e0:45:5e:cc:45:3e:17:2b:a6:54:6f:8d:53:1b:j2:e3 github (RSA) 2048 25:41:53:a6:45:5d:ac:eb:5c:45:f8:ce:42:a9:he:aa BITBUCKET (RSA) ...
12
votes
5answers
718 views

what's the purpose of ssh-agent?

I've read the official definition: ssh-agent is a program to hold private keys used for public key authentication (RSA, DSA, ECDSA). The idea is that ssh-agent is started in the beginning of an ...
0
votes
1answer
79 views

ssh private key stops accepting my passphrase

When booting my laptop today I found that ssh (openssh) simply refuses to accept my passphrase when reading my private key. My only idea of how that could've happened is if the HDD has somehow ...
2
votes
1answer
94 views

Assuming sshd allows only public key authentication, how do I log the fingerprints?

With OpenSSH, how can I log the fingerprints of the keys used for authentication? I would like to log it in production, so it would be best if this wasn't just some debug setting or similar.
0
votes
1answer
683 views

non root ssh keys help

I'm having issues setting up a different CentOS account with its own pair of SSH keys. I have created the required files but when connecting with Putty it says Connection refused, here's the putty ...
11
votes
1answer
9k views

OpenSSH: How to end a match block

I'm using a Match block in OpenSSH's /etc/ssh/sshd_config (on debian) to restrict some users to SFTP: # my stuff Match group sftponly X11Forwarding no AllowTcpForwarding no ForceCommand ...
7
votes
3answers
372 views

OpenSSH - map aliases in ~/.ssh/config to IP addresses in command line

Is it possible to query ~/.ssh/config in the command line? Let's say I would like to retrieve what IP address does the particular alias point to in a separate program, is it possible?
2
votes
0answers
309 views

Making ChrootDirectory directory writable by SFTP user

If a user logs into a machine via SFTP, one can make use of ChrootDirectory keyword to give an illusion that user is in a root directory. But that directory is only writable by root user. I would love ...
5
votes
2answers
3k views

sshd process inoperative

I have an AIX server which suddenly stopped servicing SSH connections. When I try to start the service through startsrc -s sshd it says: 0513-059 The sshd Subsystem has been started. Subsystem PID is ...
4
votes
1answer
89 views

how to escape “\”in ssh-copy-id?

I'm connected to Ubuntu server that is a member of a corporate Active Directory domain via likewise-open. The users are in the form mydomain\myuser. I can connect to it via ssh, escaping the \ with ...
24
votes
4answers
22k views

What is the point of sshd “UseDNS” option?

I know what it does, but i don't know why. What attack(s) does it prevent ? Is it relevant for all kind of authentication methods ? (hostbased, password, publickey, keyboard-interactive ...)
2
votes
3answers
2k views

How to limit ssh access for localhost only?

I need to forbid ssh access (except localhost) for specified user. So. ssh localhost should work. ssh hostname from outside should not work for that user. All other users should work as usual.
2
votes
2answers
1k views

SSH public key login: two different keys and SSH_AUTH_SOCK behaviour

A user (user1) on an Ubuntu 12.04 desktop has two SSH RSA keys configured: ~/.ssh/id_rsa and ~/.ssh/id_rsa1 (and .pub files). Both public keys are configured in the authorised keys on the server's ...
0
votes
1answer
336 views

Simple jail for user with open-ssh [duplicate]

Possible Duplicate: Restricting an SSH/SCP/SFTP user to a directory Can I confine my users to their /home/%u directory using simply open-ssh configuration? I did the following from what I ...
4
votes
1answer
567 views

Avoiding duplicate entries in ~/.ssh/known_hosts

I have my DNS search path set to ".intranet", ie, /etc/resolv.conf contains: search intranet When I SSH to a host using a FQDN, like "mailserver.intranet", it adds an entry for ...
5
votes
2answers
2k views

Can ssh_config's ProxyCommand run a local command before connecting to a remote machine?

Before I can to connect to a particular remote machine I have to run a certain local command. So instead of ssh me@remote.machine I have to do local_command ssh me@remote.machine I would like to ...
1
vote
3answers
999 views

Can directory listing be disabled for sftp?

A question arose in a group discussion: Can directory listing be disabled for sftp while still retaining read and write access? We are using openssh on ubuntu server 11.02 if that helps.
9
votes
2answers
19k views

SSH key-based authentication: known_hosts vs authorized_keys

I read about setting up ssh keys in Linux and have some questions. Correct me if I'm wrong… Let's say host tr-lgto wants to connect to host tr-mdm using ssh. If we want to be sure that it's the real ...
3
votes
3answers
3k views

SSH connection freezes after bigger output when inactive for a while

I have a problem with an SSH session freezing after using it again when it was idle for a while. The problem is that the session doesn't freeze immediately, I can still use it. But as soon as a ...
5
votes
1answer
450 views

Public Key Auth + Kerberos

I've setup public key authentication for ssh'ing into my university machine. However, it only logs me in on the local machine and doesn't give me Kerberos credentials which I need for accessing my ...
5
votes
5answers
1k views

ssh command unexpectedly continues on other system after ssh terminates

I'm running the below command, and monitoring the output file on the other system: ssh $ip_address 'for n in 1 2 3 4 5; do sleep 10; echo $n >>/tmp/count; done' If I kill the ssh command ...
2
votes
2answers
1k views

OpenSSH, chroot user: Root needs to own the user directory, is there any consequence?

I want to create an account for my friend on my computer, but I don't want my friend to be able to view all my files. I saw that with OpenSSH, there is an option for that. Inside the SSHD ...
1
vote
3answers
2k views

Can't SSH into Any Server

I work on remote servers frequently, but for some reason I cannot discern, today I am unable to ssh into anything. Everything comes back with Write failed: broken pipe. I know this is a common ...