I have a weird ssh issue that I haven't encountered previously.
Remote connections to a machine (theseus) hang after < 1s.
Connecting from theseus to theseus (ssh user#localhost or ssh user#ip) is fine.
Connecting from theseus => other machine is fine.
theseus => other machine => theseus connects but hangs after <1s.
session negotiation looks ok in /var/log/auth.log (sshd says "session opened for user", systemd-logind says "new session # of user", there doesn't seem to be an error after that)
from othermachine ssh user#theseus 'while date +%s.%N; do sleep 0.1 || break; done' shows ~0.75s worth of output
the process continues running on theseus after this time, but I get no output, I can ctrl + c the process
I reinstalled ssh-server and client on theseus and the only edit I've made to sshd_config is UseDns no.
Related
Vscode insiders stopped to work with remote today morning after (unavoidble) update. It doesn't show remote directory, saying
Connection error: Unauthorized client refused.
and
Failed to connect to the remote extension host server (Error:
Connection error: Unauthorized client refused.)
Deletion of all remote vscode files and killing vscode processes didn't help.
The following transcript can be seen in Output tab:
remote-ssh#0.44.0
linux x64
SSH Resolver called for "ssh-remote+myserver", attempt 1
SSH Resolver called for host: myserver
Setting up SSH remote "myserver"
Using commit id "MYHASH" and quality "insider" for server
Testing ssh with ssh -V
ssh exited with code: 0
Got stderr from ssh: OpenSSH_7.6p1 Ubuntu-4ubuntu0.3, OpenSSL 1.0.2n 7 Dec 2017
Install and start server if needed
> Found existing installation at /home/dimskraft/.vscode-server-insiders/bin/MYHASH...
> Found running server...
>
> *
> * Reminder: You may only use this software with Visual Studio family products,
> * as described in the license (https://go.microsoft.com/fwlink/?linkid=2077057)
> *
>
> Checking server status with wget
> ==MY-GUID==
"install" terminal command done
Received install output: ==MY-GUID==
Server is listening on port 35693
Spawning tunnel with: "ssh" -L 127.0.0.1:35693:127.0.0.1:35693 -o ConnectTimeout=15 "myserver" bash << 'EOSSH'
echo -e 'Connected to SSH Host - Please do not close this terminal' && sleep infinity
EOSSH
> Connected to SSH Host - Please do not close this terminal
Spawned SSH tunnel between local port 35693 and remote port 35693
Waiting for ssh tunnel to be ready
Tunneling remote port 35693 to local port 35693
Resolved "ssh-remote+myserver" to "127.0.0.1:35693"
------
Downgrading to 1.36.0-insider helped
I want to connect from my home pc with VPN (ubuntu-18.04) to work pc (ubuntu 18.04) using x2go.
Server side installation:
sudo add-apt-repository ppa:x2go/stable
sudo apt-get update
sudo apt-get install x2goserver x2goserver-xsession
Client side installation:
sudo apt-get install x2goclient
I am able to ssh to my remote desktop, but x2go doesn't work. Problem seems to be in the server side, since I tried to x2go connect from different computer (CentOs) and error was the same.
Client session preferences window:
I tried almost everything in session preferences, even with RSA key (I have it) or single application session type and many else, always the same error.
Client debug log: (x2goclient --debug)
x2go-INFO-1> "Starting X2Go Client 4.1.2.1..." x2go-WARNING-1> English
language requested, not loading translator. x2go-WARNING-1> English
language requested, not loading translator. Object::connect: No such
slot ONMainWindow::slotCheckAgentProcess() x2go-INFO-3> "Started X2Go
Client." x2go-DEBUG-../src/onmainwindow.cpp:563> "$HOME=/home/XXX"
x2go-DEBUG-../src/onmainwindow.cpp:2242> Reading 1 sessions from
config file. x2go-DEBUG-../src/sessionbutton.cpp:342> Creating QPixmap
with session icon: ":/img/icons/128x128/x2gosession.png".
x2go-DEBUG-../src/onmainwindow.cpp:12843> libssh not initialized yet.
Initializing. x2go-DEBUG-../src/onmainwindow.cpp:2728> Creating
QPixmap with session icon: '":/img/icons/128x128/x2gosession.png"'.
x2go-DEBUG-../src/onmainwindow.cpp:2795> Starting session via Smart
Card, SSH Agent or Kerberos token. x2go-INFO-8> "Starting connection
to server: 192.168.29.15:22" x2go-DEBUG-../src/onmainwindow.cpp:2829>
Starting new ssh connection to server:"192.168.29.15":"22" krbLogin:
false x2go-DEBUG-../src/sshmasterconnection.cpp:175>
SshMasterConnection, host "192.168.29.15"; port 22; user "XXX";
useproxy false; proxyserver "192.168.29.15"; proxyport 22
x2go-DEBUG-../src/sshmasterconnection.cpp:248> Starting SSH connection
without Kerberos authentication.
x2go-DEBUG-../src/sshmasterconnection.cpp:252> SshMasterConnection,
instance SshMasterConnection(0x56102247dbe0) created.
x2go-DEBUG-../src/sshmasterconnection.cpp:520> SshMasterConnection,
instance SshMasterConnection(0x56102247dbe0) entering thread.
x2go-DEBUG-../src/sshmasterconnection.cpp:840> Session port before
config file parse: 22 x2go-DEBUG-../src/sshmasterconnection.cpp:850>
Session port after config file parse: 22
x2go-DEBUG-../src/sshmasterconnection.cpp:915> Session port before
config file parse (part 2): 22
x2go-DEBUG-../src/sshmasterconnection.cpp:925> Session port after
config file parse (part 2): 22
x2go-DEBUG-../src/sshmasterconnection.cpp:950> cserverAuth
x2go-DEBUG-../src/sshmasterconnection.cpp:991> state: 1
x2go-DEBUG-../src/sshmasterconnection.cpp:1364> userAuthAuto failed:""
(code 1)
x2go-DEBUG-../src/sshmasterconnection.cpp:1274> Trying password
mechanism if available.
x2go-DEBUG-../src/sshmasterconnection.cpp:1278> Password mechanism
available. Continuing.
x2go-DEBUG-../src/sshmasterconnection.cpp:726> User authentication OK.
x2go-DEBUG-../src/sshmasterconnection.cpp:1789> LOGIN CHECK:"LOGIN OK
" x2go-DEBUG-../src/sshmasterconnection.cpp:1792> don't have
interaction x2go-DEBUG-../src/sshmasterconnection.cpp:1825> LOOP
FINISHED x2go-DEBUG-../src/sshmasterconnection.cpp:1829> No
interaction needed, continue session
x2go-DEBUG-../src/sshmasterconnection.cpp:735> Login Check - OK
x2go-DEBUG-../src/onmainwindow.cpp:2923> SSH connection established.
x2go-DEBUG-../src/onmainwindow.cpp:3336> Continue normal X2Go session
x2go-DEBUG-../src/sshprocess.cpp:199> Executing remote command via
SshProcess object 0: "x2golistsessions"
x2go-DEBUG-../src/sshprocess.cpp:213> this=SshProcess(0x5610224a1f30)
Running masterCon->addChannelConnection(this, '
"1d4dfc1a-7f4d-4f00-b39e-07273d3d973d" ', ' "bash -l -c 'echo
"X2GODATABEGIN:1d4dfc1a-7f4d-4f00-b39e-07273d3d973d"; export
PATH="/usr/local/bin:/usr/bin:/bin";export TERM="dumb";
x2golistsessions; echo "X2GODATAEND:1d4dfc1a-7f4d-4f00-b39e-07273d"
'); x2go-DEBUG-../src/sshmasterconnection.cpp:1891> Locking SSH
channel connection MUTEX.
x2go-DEBUG-../src/sshmasterconnection.cpp:1893> Passing new channel
connection object to channelConnections.
x2go-DEBUG-../src/sshmasterconnection.cpp:1895> Unlocking SSH channel
connection MUTEX. x2go-DEBUG-../src/sshmasterconnection.cpp:2083>
Creating new channel.
x2go-DEBUG-../src/sshmasterconnection.cpp:2100> New
channel:0x7fcf84012aa0
x2go-DEBUG-../src/sshmasterconnection.cpp:2185> Executing remote:
"bash -l -c 'echo
"X2GODATABEGIN:1d4dfc1a-7f4d-4f00-b39e-07273d3d973d"; export
PATH="/usr/local/bin:/usr/bin:/bin";export TERM="dumb";
x2golistsessions; echo
"X2GODATAEND:1d4dfc1a-7f4d-4f00-b39e-07273d3d973d";'"
x2go-DEBUG-../src/sshmasterconnection.cpp:2208> New exec channel
created.
x2go-DEBUG-../src/sshmasterconnection.cpp:2257> EOF on channel
0x7fcf84012aa0; SshProcess object: 0
x2go-DEBUG-../src/sshmasterconnection.cpp:2380> EOF sent.
x2go-DEBUG-../src/sshmasterconnection.cpp:2384> Channel closed.
x2go-DEBUG-../src/sshprocess.cpp:526> SSH finished: raw output
(stdout): "" x2go-DEBUG-../src/sshprocess.cpp:532> Have stderr only,
something must be wrong. x2go-DEBUG-../src/sshprocess.cpp:537> SSH
finished: false - "bash: bash: command not found " (0).
x2go-DEBUG-../src/onmainwindow.cpp:3804> "bash: bash: command not
found
If someone was interested, I can show server's side /var/log/syslog
Thank you for your help
Please try moving your .bashrc aside and retry.
It was my bad, silly me. I had a typo in /etc/environment file and I didn't notice it because I haven't restarted my PC after that typo. After fixing it, it worked.
I'm having problem accessing one of my VMs (called myvm1 here) after having restored a disk from a snapshot. Here is what I did yesterday (which worked just fine):
I made a snapshot of disk1.
I created a new disk, called disk2, using the snapshot created above.
I attached the disk to myvm1 though Google Console.
I unmounted disk1 and mounted disk2.
I deleted disk1.
Everything worked fine, and database data on disk2 was accessible as desired. There's not much else on that disk.
Today, what I wanted to do, was to "rename" disk2 to disk1 (to avoid future problems with our Terraform setups). I did this by doing the following:
I made a snapshot of disk2.
I created a new disk, calling it disk1, using the snapshot above.
I attached the disk to myvm1 using the terminal:
gcloud compute --project=myproject instances attach-disk myvm1 --disk disk1
After this, when I attempted to ssh into myvm1 (to unmount and mount), I get a
ssh: connect to host myvm1 port 22: Connection refused
I have attempted the following to solve this/investigate:
stopping and starting the VM (takes a considerably longer time than other VMs in the same project) repeatedly
detaching disk1 (and re-attaching it)
Other information:
other VMs in the same project are still accessible via ssh.
I did nothing else to the VM yesterday or today but what I have written above. The system has not been in use between yesterday and now (it was shut down over night to save money).
Using the Google Console SSH does not work, BUT it does not work for the other VMs either, as we connect using private keys.
"The instance is booting up and sshd is not yet running." - It's listed as RUNNING.
"The instance is not running sshd." I have not manually disabled sshd.
"sshd is listening on a port other than the one you are connecting to." I've made no changes to ports.
"There is no firewall rule allowing SSH access on the port." Also, under "Firewall rules and routes details" port 22 is enabled. Also, firewall rules are identical to the other VMs in the same project.
"The firewall rule allowing SSH access is enabled, but is not configured to allow connections from GCP Console services." We don't want to be able to connect via GCP Console so that doesn't matter.
"The instance is shut down." - It's running.
Debug information for the ssh-call:
me#mycomputer:~/project$ ssh myvm1 -vvv
OpenSSH_7.2p2 Ubuntu-4ubuntu2.4, OpenSSL 1.0.2g 1 Mar 2016
debug1: Reading configuration data /home/me/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "myvm1" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to myvm1 [10.23.0.3] port 22.
debug1: connect to address 10.23.0.3 port 22: Connection refused
ssh: connect to host myvm1 port 22: Connection refused
I've looked at the solution mentioned here
Why Google Cloud Compute Engine instance gives ssh connection refused after restart?
but since I have not yet mounted/unmounted any of the disks I don't see how that could be the same problem.
I would very much appreciate any help you can give me. Solutions involving creating a new instance are not relevant, as I want to know what went wrong in the first place, so that this does not happen in a production environment. Thankfully myvm1 is just a sandbox system.
A port 22 error can come from two sources: firewall not properly set up on GCP or port 22 not accepting SSH connections from within your instance. Assuming that firewall is properly set up since it works on other instances, please try to log in with serial console and check your iptable.
In order to connect to serial console you will have to perform the following:
1). Activate the “Connect to serial console” button.
Go to VM instances, click on your VM, Edit, and active “enable connecting to serial ports” in the Remote access area and click on save.
2). Create a username and password.
Go to Vm instance, click on your Vm again, Edit, and fill up the custom metadata section with:
In key: startup-script
In value:
#!/bin/bash
sudo useradd -G sudo pamela
sudo echo 'pamela:pamela5' | chpasswd
(This is a script that creates a username : pamela and password: pamela5, which you are going to use later. Please use something else for security purposes)
3). A reboot is needed for changes to take effect.
I had the same problem. I think the snapshot file is corrupted.
I have a few scripts running on a remote machine that I have ssh access to. I connect on my local machine (Mac) in terminal using TMUX. I create a new session using $ tmux new and ssh into the machine. I start my scripts and everything is great. I detach using Ctrl-b d and the scripts continue running. However, after my local machine gets rebooted or goes to sleep, the scripts on the remote machine stop. When I reload the the session using tmux attach -t <session name> I see the following error:
packet_write_wait: Connection to <remote ip> port 22: Broken pipe
That suggests that the session ended. What can I do to ensure that the scripts continue to run no matter what happens on my local machine?
I want to debug a process running on a remote box from my host box (I built the code on the host machine).
Both have linux type operating systems.
I seems I can only communicate to the remote box from the host box via ssh (I tested using telnet).
I have followed the following steps to set this up:
On the Remote box:
Stop the firewall service:
service firewall_service stop
Attach the process to gdbserver
--attach :remote_port process_id
On the Host box:
Set up port forwarding via ssh
sudo ssh remote_username#remote_ip -L host_port:localhost:remote_port
-f sleep 60m
Set up gdb to attach to a remote process:
gdb file.debug
(gdb) target remote remote_ip:remote_port
When I try to start the debugging on the host by running 'target remote remote_ip:remote_port' on the host box I get a 'Connection timedout' error.
Can you guys see anything I am doing wrong, anything to check or an alternative way to debug remotely over ssh I would be grateful.
Thanks
This command:
sudo ssh remote_username#remote_ip -L host_port:localhost:remote_port ...
forwards local host_port to remote_port on remote_ip's localhost. This is useful only if you could not just connect to remote_ip:remote_port directly (for example, if that port is blocked by firewall).
This command:
(gdb) target remote remote_ip:remote_port
asks GDB to connect to remote_port on remote_ip. But you said that you can only reach remote_ip via ssh, so it's not surprising that GDB times out.
What you want:
ssh remote_username#remote_ip -L host_port:localhost:remote_port ...
(gdb) target remote :host_port
In other words, you connect to local host_port, and ssh forwards that local connection to remote_ip:remote_port, where gdbserver is listening for it.