Related
I am trying to download a configuration file, which will automate os installation, from a tftp server to a libvirt virtual macine guest . I can download file from host without problem but it can not be download in guestos. From guesos, I can ping the server, the curl -O tftp://serverip/file command stucks. I can see that the server is accessed but somehow tftp protocol related traffic is not being forwarded completely I believe.
I have found an old post at tftp-for-libvirt-hosts-behind-nat, I have changed nic card to e1000, but the behaviour has not changed.
Another post at iptables rules to forward tftp via NAT which is completely foreing to me.
Any help much appreciated.
Please check this Topology diagram.
I have created 2 virtualbox VMs using ubuntu 16.04.4 TLS, call them VM1 and VM2.
I am running two containers on VM1, call them VM1-C1 and VM1-C2.
I am running two containers on VM2, call them VM2-C1 and VM2-C2.
VM1 and VM2 are connected directly using internal-network(vagrant has option).
Now, I need to steer traffic from VM1-C1 to VM2-C1 and then to internet via linux bridges.
And steer traffic from VM1-C2 to VM2-C2 and then to internet via linux bridges.
Is it possible to achieve this using linux bridges?
I created veth pairs [if1, if3], [if2, if4], [if5, if7], [if6, if8], [if9, if11], [if10, if12] to achieve this(I'll think of any optimizations or you can suggest me better options).
I configured IPs on if1 and if7 from subnet 192.16.1.0/24.
I configured IPs on if2 and if8 from subnet 192.16.2.0/24.
When I try to ping if7(192.16.1.10) from if1(192.16.1.1), I see the arp is reaching if7 and ARP reply is seen at eth0 of VM2.
But ARP reply is not seen at eth0 of VM1.
Any help is greatly appreciated.
Thanks in advance.
I am using Vmware Player to use Ubuntu 14.04 but I am unable to get any internet connection in my virtual machine even though my system is connected to the internet. The original OS in my system is Windows 7. Can anybody suggest the way out.
Found the solution by browsing through multiple threads. Compiling it here.
EDIT : Please check if your network is in bridged mode or not if you are using VMWare/ VirtualBox before following the steps below. Enabling bridge mode and restarting guest OS can resolve the issue.
First check if your network is disabled by using the following cmd in terminal:
sudo lshw -C network
If it shows disabled after the name of your adapter ( note down the logical name for later use)
*-network DISABLED
description: Ethernet interface
product: 82545EM Gigabit Ethernet Controller (Copper)
vendor: Intel Corporation
physical id: 1
bus info: pci#0000:02:01.0
logical name: ens33
All we need to do is enable the adapter, so lets get started.
open up your interfaces file by using the following cmd:
sudo gedit /etc/network/interfaces
My file had the following data written:
auto lo
iface lo loopback
But the logical name of my NIC was ens33 ( not lo), so i changed it to read the following and saved the file.
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
auto wlan0
iface wlan0 inet dhcp
Now time to restart the networking service.
sudo /etc/init.d/networking restart
check if network is back up, it shouldn't have that disabled tag anymore.
sudo lshw -C network
Enjoy your internet :)
If that doesn't work -> But as explained earlier change the network adaptor settings to bridged in your virtual machine settings.
If all that does not work, the best way to resolve the issue is
Restore your VM network settings
If you are using an older version download a new version (trial version would also work) - we are just updating your settings
Follow the steps:
Depending on how you are connected to the network, try either Bridged or NAT mode for the VM's network adapter. Keep in mind that you may lose connectivity from the host machine to the VM. In this case you'll need another network adapter.
In most cases NAT should work. In this case only your host machine's IP is visible to the network, and ports are allocated for the VM to communicate to the outside world. The problem is that you can't connect to the VM from the host machine if you need to. Add another adapter as I mentioned above and connect to its IP address. You will have two adapters - one for the Internet and the other for host-to-guest.
In the bridge mode the VM is visible to the outside network, so a network configuration is required that enables the VM to get an IP address and participate in the network (for example, network administrators may block unknown MAC addresses). The host machine talks with the VM as it were just a computer on the network.
Update your question with additional information if my suggestion does not work: guest OS, how your host computer is connected to the network, what the current configuration of the VM's network adapters is. Is it a home or a workplace computer?
UPDATE
So I guess if you are connected to a corporate LAN, then NAT will work while Bridge will not. To add another interface 1) add an adapter in VMWare Player; 2) Add an interface in Ubuntu. Assuming your existing interface is eth0, edit /etc/network/interfaces, adding these lines:
auto eth1
iface eth1 inet dhcp
Then restart the networking service:
sudo /etc/init.d/networking restart
UPDATE 2
Another reason for your not being able to connect to the Internet may be a proxy server. Make sure that the proxy configuration in the VM is the same as in the host machine.
CLose VM,
Go to VM Settings and Network adapters
Then click on adapter 1 and select Shared Networking NAT.
Start VM
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
This question does not appear to be about a specific programming problem, a software algorithm, or software tools primarily used by programmers. If you believe the question would be on-topic on another Stack Exchange site, you can leave a comment to explain where the question may be able to be answered.
Closed 3 years ago.
Improve this question
I'm working on a balloon project with a Raspberry Pi. When we potentially recover the Raspberry Pi, it will most likely be in a rural location and I'd like to turn off the Pi at that point safely.
Without a router or network nearby, I was wondering if there is a way to hook up a Raspberry Pi with an Ethernet cable directly to a laptop?
It's a solution for Ubuntu (the idea also works for Windows or Mac) I just tried today and it works like a charm.
Material
a cross-over Ethernet cable (the name is fancy but it's just a normal Ethernet cable)
a laptop (ubuntu)
a Raspberry Pi (I have the Pi2)
Prerequisites on your ubuntu
Install network-manager
$sudo apt-get install network-manager
Install nmap
$sudo apt-get install nmap
Edit Wired connection on your laptop (Ubuntu)
Change IpV4 settings to "Share to other computers"
Save the setting
Reboot your laptop
Share WiFi connection of your laptop via Ethernet crossover cable
Hook up your RPi with your laptop using the Ethernet cable
Look up the broadcast address of the Ethernet connection (Laptop),
$/sbin/ifconfig eth1 | grep "Bcast" | awk -F: '{print $3}' | awk '{print $1}' 10.42.0.255
Use this address to find out the IP address of your RPi, it's 10.42.0.96 in my case because 10.42.0.1 is my laptop
$nmap -n -sP 10.42.0.255/24
Starting Nmap 6.40 ( http://nmap.org ) at 2016-02-20 23:07 CET
Nmap scan report for 10.42.0.1
Host is up (0.00031s latency).
Nmap scan report for 10.42.0.96
Host is up (0.0023s latency).
Nmap done: 256 IP addresses (2 hosts up) scanned in 2.71 seconds
Login to your RPi from your laptop (-Y with X-forwarding)
$ssh -Y pi#10.42.0.96
Lo and behold! Now your RPi is connected to your laptop and RPi can share the WiFi connection.
pi#raspberrypi ~ $
Share display & keyboard of your laptop with RPi
Install vncserver on Raspberry Pi
$ sudo apt-get update
$ sudo apt-get install tightvncserver
Install vncviewer on your laptop by downloading RealVNC (it supports multiple platforms)
http://www.realvnc.com/download/vnc/
To be able to copy & paste from VNC server <--> VNC viewer, you need to install autocutsel on your RPi.
$sudo apt-get install autocutsel
If this site doesn't work, try to download the .deb directly from a mirror site, e.g.
mirror.hmc.edu/debian/pool/main/a/autocutsel/autocutsel_0.10.0-1_armhf.deb
and install it
$sudo dpkg -i autocutsel_0.10.0-1_armhf.deb
Start vncserver on your RPi (You have to restart vncserver after installing autocutsel, you can issue $vncserver -kill :1)
$vncserver :1
Add autocutsel -fork to /home/pi/.vnc/xstartup
#!/bin/sh
xrdb $HOME/.Xresources xsetroot -solid grey
autocutsel -fork
#x-terminal-emulator -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" &
#x-window-manager &
# Fix to make GNOME work
export XKL_XMODMAP_DISABLE=1
/etc/X11/Xsession
Start vncviewer on your laptop
$vncviewer
A vncviewer window will pop up and type in the IP address of your RPi (given by your laptop) followed by port 1, which is your VNC server. for example: 10.42.0.96:1 in my case.
Connect it to the vncserver hosted on your RPi by typing in a password (set up a password yourself)
12.Now you can see the desktop of RPi on your laptop, and I opened my browser to show the shared WiFi connection is working as well.
See Raspberry Pi desktop on your ubuntu
No router + no screen + regular Ethernet cable + RPI 2 + Raspbian Lite 2018-11-13 + Ubuntu 18.10
First we must enable the SSH server on the Pi, which is disabled by default for security.
If you already have a shell on the Pi through a non-SSH method such as screen + keyboard or UART (see below), just run:
sudo systemctl enable ssh
sudo service sshd start
as explained at: https://raspberrypi.stackexchange.com/questions/58478/ssh-not-working-with-fresh-install This persists across boots.
Otherwise, insert he SD card on your host, and create a magic empty file named ssh file in the boot/ partition.
On Ubuntu hosts, it gets mounted automatically and you can do just:
sudo touch /media/$USER/boot/ssh
which you can confirm with:
lsblk
which contains:
mmcblk0 179:0 0 14.4G 0 disk
├─mmcblk0p1 179:1 0 43.9M 0 part /media/ciro/boot
└─mmcblk0p2 179:2 0 14.4G 0 part /media/ciro/rootfs
If you don't enable the SSHD daemon on the Pi then SSH connection will fail with:
ssh: connect to host 10.42.0.160 port 22: Connection refused
when we try it later on.
After enabling the SSH server
Next, boot the Pi, and link an Ethernet cable from your laptop directly to the Pi:
On Ubuntu 17.04 to work around this bug as mentioned on this answer you first need:
sudo apt-get install dnsmasq-base
On the host, open the network manager:
nm-connection-editor
And go:
+ sign (Add a new connection)
Ethernet
Create
IPv4 Settings
Method: Shared to other computers
Set a good name for it
Save
Find the IP of the Pi on host:
cat /var/lib/misc/dnsmasq.leases
outputs something like:
1532204957 b8:27:eb:0c:1f:69 10.42.0.160 raspberrypi 01:b8:27:eb:0c:1f:69
10.42.0.160 is the IP, then as usual:
ssh pi#10.42.0.160
I also have the following in my .bashrc:
piip() ( cat /var/lib/misc/dnsmasq.leases | cut -d ' ' -f 3; )
pissh() ( sshpass -p raspberry ssh "pi#$(piip)"; )
From inside the Pi, notice that it can access the internet normally through your host's other interfaces:
ping google.com
For example on my laptop, the Pi takes up the Ethernet, but the host is also connected to the internet through WiFi.
The crossover cable is not required if the host network card supports Auto MDI-X. This is the case for most recent hardware, including for example the 2012 Lenovo T430 I tested with, which has an "Intel® 82579LM Gigabit Network Connection" which documents support for Auto MDI-X.
Now you can also:
access the Internet from the PI through your Ubuntu's Wifi connection
open a VNC to get rid of the display as well: https://raspberrypi.stackexchange.com/questions/14611/how-to-set-up-raspberry-pi-without-a-monitor/54393#54393
UART serial USB converter
This is an alternative to SSH if you just want to get a shell on the Pi: https://en.wikipedia.org/wiki/Serial_port
This does not use SSH or networking itself, but rather the older, simpler, more direct, more reliable, lower bandwidth, lower distance serial interface. The Pi won't have access to the Internet with this method.
Desktop computers still have a serial port which you can connect directly wire to wire with the Pi, but these are hidden in most laptops, and so we need to buy a cheap USB adapter. Here I've used a "DSD TECH USB to TTL Serial Converter" https://www.amazon.co.uk/gp/product/B072K3Z3TL See also: https://unix.stackexchange.com/questions/307390/what-is-the-difference-between-ttys0-ttyusb0-and-ttyama0-in-linux/367882#367882
First plug the SD card on the host, and edit the config.txt file present in the first partition to add:
enable_uart=1
as explained at: https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=141195
This first partition contains the bootloader, its configuration files and the (Linux / your) kernel, config.txt being one of them. The second partition contains the actual Linux root filesystem.
Now connect your computer to the Pi as:
You only need to attach 3 cables:
Ground to Ground
Tx on Pi to Rx on the USB to serial port
Rx on Pi to Tx on tye USB to serial port
This is also documented at: https://www.raspberrypi.org/documentation/usage/gpio/README.md
Be careful not to link the Ground to the 5V, I've already burned 2 UART to USB chips and a RPI UART by doing that!
You don't need to connect the 5V to the 5V at all. I think you can power your Pi like that, but I've read that this is a bad idea, just use the usual USB power source.
Finally, plug the USB side of the connector to your host computer, and get a shell with:
sudo apt install screen
sudo usermod -a -G dialout $USER
screen /dev/ttyUSB0 115200
Exit with Ctrl-A \.
Here is a video by Adafruit showing it: https://www.youtube.com/watch?v=zUBPeoLW16Q
See also
Similar question on RPI SE: https://raspberrypi.stackexchange.com/questions/3867/ssh-to-rpi-without-a-network-connection
You don't need a cross-over cable. You can use a normal network cable since the Raspberry Pi LAN chip is smart enough to reconfigure itself for direct network connections.
Cheers
I've just implemented and test this successfully. Same situation with my project, want to connect to a Raspberry Pi with no router or wifi. Just a simple ethernet cable.
Using ssh putty program put the address as
raspberrypi.local
Log and in and you can access the terminal.
Alternatively if VNC server is setup, use VNC server and put
raspberrypi.local:1
In the server address. input your VNC server password and you've now got GUI access to do what you want.
In may case it was run scripts in a remote location. In the posters situation, safely shutdown the Pi. Simples Pimples.
Configure static ip for your laptop and raspberry pi.
On the rapberryPI configure it as following.
pi#rpi>sudo nano /etc/network/interfaces
Then configure following as required to connect to your laptop.
iface eth0 inet static
address 192.168.1.81
netmask 255.255.255.0
broadcast 192.168.1.255
configure static ip on the raspberry pi:
sudo nano /etc/network/interfaces
and then add:
iface eth0 inet static
address 169.254.0.2
netmask 255.255.255.0
broadcast 169.254.0.255
then you can acces your raspberry via ssh
ssh pi#169.254.0.2
Here are the instructions for Windows users on connecting to a RPi by using just an Ethernet cable and a DHCP server. There is no need for a cross over cable, as the RPi can handle it. I have a blog post that documents this with pictures here which may be easier to follow.
Downloads
Download the DHCP Server for Windows (download link is here). Unzip the zip file and open the dhcpwiz application, which will configure the DHCP server.
DHCP Server Configuration
Hit next on the first screen.
On the second screen, look for a "Local Area Connection" row and verify its IP address is 0.0.0.0 and its status is enabled. Connect the Ethernet cable from the RPi to your laptop, and turn on the Pi. Hit refresh on this screen until the IP address changes to 169.254.*.*. If it is anything else then you should alter your network settings for the Local Area Connection (make sure it is not a static IP/DNS). Click on this Local Area Connection row and hit next.
Check HTTP (Web Server). This makes it much more easy to locate the RPi's IP address. Hit Next.
Take the defaults and hit Next until you get to the Writing the INI file screen. Check Overwrite existing file and hit the Write INI file button. Then hit Next.
On the final screen, check Run DHCP server immediately and hit `Finish.
DHCP Server and Obtaining the IP Address of your Raspberry PI
This launches the actual DHCP server, using the configuration you just created in the previous wizard. Click the Continue as tray app button, and the DHCP server will be minimized to your system tray.
Anywhere from 1 second to 5 minutes from now you will see an alert on the system tray with your laptop and your RPi's new IP address. This alert is really quick and you will probably miss it. Normally your RPi's IP is 169.254.0.2, but it could be *.01 or even something else. It is easier to access the DHCP server's web UI at http://localhost/dhcpstatus.xml. This will list the hostname as "raspberrypi" with its IP address.
Now you can putty or remote desktop into your RPi, and configure its wireless settings or whatever you want to do.
Trouble shooting
This can be somewhat finicky. I've had my connection appear to drop and have been unable to SSH back in using the IP address. Normally, I can restart the Pi and get the IP address again. Sometimes I have to restart both the RPi and the DHCP server. Sometimes I have to do this multiple times. At one point when I wasn't getting a connection for 15 minutes, I copied all of the files in the dhcpsrv2.5.1 folder to a new folder and tried again; it immediately worked.
You could use a cross-over ethernet cable - http://en.wikipedia.org/wiki/Ethernet_crossover_cable
Assuming your RPi is a DCHP Client, then best to run a simple DHCP server on your notebook to assign the RPi an IP address.
Yes, you can connect the raspberry direct to your PC without router.
For this is necessary that the raspberry and your computer are on the same subnet, and they both have a static ip configured (And an Ethernet cable connected between the two devices).
An ideal configuration would be the following:
Raspberry on eth0: IP: 192.168.1.10 SubNet: 255.255.255.0
Your PC: IP: 192.168.1.11 SubNet 255.255.255.0
To set a manual IP on raspberry you can follow this guide
In your PC you can set a manual IP in the network adapter settings,and the procedure depends on your operating system.
When you have configured the two static IP, you can connect to the raspberry via SSH using the IP set (192.168.1.10).
Another simpler method is to attach on GPIO a button to turn off the raspberry! Take a look here!
What worked for me was a combination of the answers from Nicole Finnie and Ciro Santilli along with some answers from elsewhere.
Setting up the pi
We will need to do two things: activate ssh on the pi, and configure the pi to use a static ip.
Activating ssh
Add a file called ssh in the boot partition of the sd card (not the /boot folder in the root partition). This is well documented other places.
Static ip
Open /etc/dhcpcd.conf on the pi's SD-card, and uncomment the example for a static ip (starts around line 40). Set the addresses to
# Example static IP configuration:
interface eth0
static ip_address=10.42.0.182/24
static routers=10.42.0.1
static domain_name_servers=10.42.0.1 8.8.8.8 fd51:42f8:caae:d92e::1
Setting up your laptop
First, make sure you have networkmanager (with GUI) installed on your laptop. Then, make sure dnsmasq is not running as a service:
systemctl status dnsmasq
If this command prints that the service is stopped, then you're good.
Next we have to config networkmanager. Open /etc/NetworkManager/NetworkManager.conf and add the following two lines at the top:
[main]
DNS=dnsmasq
Then reboot. This step might not be necessary. It might be sufficient to restart the NetworkManager service. Now go to the NetworkManager GUI (usually accessed by an icon in the corner of the screen) and choose Edit Connections... In the window that pops up, click the + icon to create a new connection. Choose Ethernet as the type and press Create.... Go to the IPv4 Settings tab and select the method Shared to other computers. Give the connection a good name and save.
Connect the Raspberry Pi and make sure your laptop is using your new connection as its ethernet connection. If it is, your pi should now have an ip given to it by your pc. You can find this by first running ifconfig. This should give you several blocks of text, one for each network interface. You're interested in the one that is something like enp0s25 or eth0. It should have a line that reads something similar to
inet 10.42.0.1 netmask 255.255.255.0 broadcast 10.42.0.255
look at the broadcast address (in this case 10.42.0.255). If it is different than mine, power off the pi and put the SD card back in your laptop to change the static ip_address to something where the first three numbers are the same as in your broadcast address. Also change the static routers and the first of the domain_name_servers to your laptop's inet address. Power the pi back on and connect it. Run ifconfig again to see that the addresses have not changed.
ssh into the pi
ssh pi#10.42.0.182
If you get connection refused, the pi isn't running an ssh server. If you get host unreachable, I'm sorry.
Hope this helps someone!
Closed. This question is not about programming or software development. It is not currently accepting answers.
This question does not appear to be about a specific programming problem, a software algorithm, or software tools primarily used by programmers. If you believe the question would be on-topic on another Stack Exchange site, you can leave a comment to explain where the question may be able to be answered.
Closed last month.
Improve this question
I am trying to connect to remote server via ssh but getting connection timeout.
I ran the following command
ssh testkamer#test.dommainname.com
and getting following result
ssh: connect to host testkamer#test.dommainname.com port 22: Connection timed out
but if try to connect on another remote server then I can login successfully.
So I think there is no problem in ssh and other person try to login with same login and password he can successfully login to server.
Please help me
Thanks.
Here are a couple of things that could be preventing you from connecting to your Linode instance:
DNS problem: if the computer that you're using to connect to your
remote server isn't resolving test.kameronderdehamer.nl properly
then you won't be able to reach your host. Try to connect using the
public IP address assigned to your Linode and see if it works (e.g.
ssh user#123.123.123.123). If you can connect using the public IP
but not using the hostname that would confirm that you're having
some problem with domain name resolution.
Network issues: there
might be some network issues preventing you from establishing a
connection to your server. For example, there may be a misconfigured
router in the path between you and your host, or you may be
experiencing packet loss. While this is not frequent, it has
happenned to me several times with Linode and can be very annoying.
It could be a good idea to check this just in case. You can have a look
at Diagnosing network issues with MTR (from the Linode
library).
That error message means the server to which you are connecting does not reply to SSH connection attempts on port 22. There are three possible reasons for that:
You're not running an SSH server on the machine. You'll need to install it to be able to ssh to it.
You are running an SSH server on that machine, but on a different port. You need to figure out on which port it is running; say it's on port 1234, you then run ssh -p 1234 hostname.
You are running an SSH server on that machine, and it does use the port on which you are trying to connect, but the machine has a firewall that does not allow you to connect to it. You'll need to figure out how to change the firewall, or maybe you need to ssh from a different host to be allowed in.
EDIT: as (correctly) pointed out in the comments, the third is certainly the case; the other two would result in the server sending a TCP "reset" package back upon the client's connection attempt, resulting in a "connection refused" error message, rather than the timeout you're getting. The other two might also be the case, but you need to fix the third first before you can move on.
I got this error and found that I don't have my SSH port (non standard number) whitelisted in config server firewall.
Just adding this here because it worked for me. Without changing any settings (to my knowledge), I was no longer able to access my AWS EC2 instance with: ssh -i /path/to/key/key_name.pem admin#ecx-x-x-xxx-xx.eu-west-2.compute.amazonaws.com
It turned out I needed to add a rule for inbound SSH traffic, as explained here by AWS. For Port range 22, I added 0.0.0.0/0, which allows all IPv4 addresses to access the instance using SSH.
Note that making the instance accessible to all IPv4 addresses is a security risk; it is acceptable for a short time in a test environment, but you'll likely need a longer term solution.
If you are on Public Network, Firewall will block all incoming connections by default. check your firewall settings or use private network to SSL
The possibility could be, the SSH might not be enabled on your server/system.
Check sudo systemctl status ssh is Active or not.
If it's not active, try installing with the help of these commands
sudo apt update
sudo apt install openssh-server
Now try to access the server/system with following command
ssh username#ip_address
This happens because of firewall connection.
Reset your firewall connection from your hosting website.
It will start working.
After connecting to the server again add this to your (ufw) security
sudo ufw allow 22/tcp
There can be many possible reasons for this failure.
Some are listed above. I faced the same issue, it is very hard to find the root cause of the failure.
I will recommend you to check the session timeout for shh from ssh_config file.
Try to increase the session timeout and see if it fails again
My VPN connection was not enabled. I was trying all possible way to open up the Firwall and Ports until I realized, I am working from home and my VPN connection was down.
But yes, Firewall and ssh configurations can be a reason.
Try connecting to a vpn, if possible. That was the reason I was facing problem.
Tip: if you're using an ec2 machine, try rebooting it. This worked for me the other day :)
I had this issue while trying to ssh into a local nextcloud server from my Mac.
I had no issues ssh-ing in once, but if I tried to have more than one concurrent connection, it would hang until it timed out.
Note, I was sshing to my user#public-ip-address.
I realized the second connection only didn't work when I tried to ssh into it when on the same network, ie my home network
Furthermore, when I tried ssh user#server-domain it worked!
The end fix was to use ssh user#server-domain rather than ssh user#public-ip
I have experienced a couple of nasty issues that lead to these errors, and these are different from everyone else's answer here:
Wrong folder access rights. You need to have specific directory permissions on you ssh folders and files.
a. The .ssh directory permissions should be 700 (drwx------).
b. The public key (.pub file) should be 644 (-rw-r--r--).
c. The private key (id_rsa) on the client host, and the authorized_keys file on the server, should be 600 (-rw-------).
Nasty docker network configuration. This just happened to me on an AWS EC2 instance. It turned out that I had a docker network with an ip range that interfered with the ssh access granted by the security group and VPC. The docker network's range was e.g. 192.168.176.0/20 (i.e. a range from 192.168.176.1->192.168.191.254), whereas the security group had a range of 192.168.179.0/24; interfering with the SSH access.
I had this error when trying to SSH into my Raspberry pi from my MBP via bash terminal. My RPI was connected to the network via wifi/wlan0 and this IP had been changed upon restart by my routers DHCP.
Check IP being used to login via SSH is correct. Re-check IP of device being SSH'd into (in my case the RPI), which can be checked using hostname -I
Confirm/amend SSH login credentials on "guest" device (in my case the MBP) and it worked fine in my attempt.
I faced a similar issue. I checked for the below:
if ssh is not installed on your machine, you will have to install it firstly. (You will get a message saying ssh is not recognized as a command).
Port 22 is open or not on the server you are trying to ssh.
If the control of remote server is in your hands and you have permissions, try to disable firewall on it.
Try to ssh again.
If port is not an issue then you would have to check for firewall settings as it is the one that is blocking your connection.
For me too it was a firewall issue between my machine and remote server.I disabled the firewall on the remote server and I was able to make a connection using ssh.
my main machine is windows 10 and I have CEntOS 7 VBox
Search in your main machine for "known_hosts"
usually, known_host location in windows in "user/.ssh/known_host"
open it using notepad and delete the line where your centos vbox ip
then try connect in your terminal
in mac os user you can find known_hosts in "~/.ssh/known_hosts"
Make sure to ask the admin to authorize your device.
On Linux run:
sudo zerotier-cli listnetworks
if it returns status ACCESS DENIED ask the admin to authorize your node. This is mentioned here.
https://discuss.zerotier.com/t/solved-cant-join-network/1919
This issue is also caused if the Dynamic Host Configuration Protocol is not set-up properly.
To solve this first check if your IP Address is configured using
ping ipaddress,
If there is no packet loss and the IP Address is working fine try any other solution. If there is no response and you have 100% packet loss, it means that your IP Address is not working and not configured.
Now configure your IP Address using,
sudo dhclient -v devicename
To check your device you can use the 'ip a' command
For eg. My device was usb0 since I had connected the device through usb
This will configure an IP Address automatically and you can even see which one is configured. You can again check with the 'ip a' command to confirm.
This may be very case specific and work in some cases only but
check to see if you were previously connecting through some VPN software/application.
Try connecting again to the VPN. Worked in my case.
This happened to me after enabling port 22 with "sudo ufw allow ssh". Before that, I was getting a refusal from my machine when entering with ssh from another one. After enabling it, I thought it would work, but instead it showed the message "connection timed out". As I had just installed Ubuntu with the option of installing basic functions alongside, I checked whether I had the openssh-server with the command sudo apt list --installed | grep openssh-server. It turned out that Ubuntu had installed by defect the openssh-client instead. I uninstalled it and installed the openssh-server following the basic commands:
sudo apt-get purge openssh-client
sudo apt update
sudo apt install openssh-server
After that, a simple "sudo ufw allow ssh" worked perfectly and I was finally able to access the machine with an ssh command.
What worked for me was that i went to my security group and reset my IP and it worked
Here are some considerations which i took to resolve a similar issue that I had:
Port 22
IGW (Internet Gateway)
VPC
Scene 1> This is for port 22 not enabled with right configurations. If the port is set to custom or myip, the probable scene is this won't work.
Scene 2> When you delete the internet gateway, the network is created and the instance will be functional too, but the routing from the internet will not work. Hence make sure that if there is a VPC, it has an Internet Gateway attached.
Scene 3> Check the VPC for the subnet associations and routing table entries. This might probably tell you the cause. I found one in this kind of troubleshooting. The route used to land up in a "blackhole" (shows up in the route table section of the console). To fix this I had to check and find out my internet gateway and found the issue with the IGW.
Moral of the story: always trace backward in the network!
In my case I'm on windows, I reset my firewall settings, and it fixed
If you get any error check the basic a version control request with ssh -V and If it is not installed, install it with the sudo apt-get install openssh-server command.
Check your virtual machine ssh connection with sudo service ssh status at console.
Check "Active" rows and if write a inactive(dead) the console write sudo service ssh start
Result: Now you can check your connection with sudo service ssh status command and send ssh connection request.
Reset the firewall and reboot your VPS from your hosting service, it will start working perfectly fine
check whether accidentally you have deleted the default vpc or default subnets ,while creating your own vpc and subnets.
I have done this mistake while creating vpc, hence got this error while connecting via ssh.
alos check whether u have attched IGW to public subnets.
Its not complicated.
First, go disable your firewall(USE YOUR CONTROL PANEL)after you check if your openssh is active.
Disable firewall, then use putty or any alternative to basically disable using this command sudo ufw disable
try now
Update the security group of that instance. Your local IP must have updated. Every time it’s IP flips. You will have to go update the Security group.