When trying to ssh to a machine using a public key, we got the following error:
ssh '[email protected]'
sign_and_send_pubkey: signing failed for RSA "/home/tux/.ssh/id_rsa" from agent: agent refused operation
The problem was with the local .ssh folder which had wrong permissions set. To fix the above problem, we issued the following commands:
chmod 700 ~/.ssh;
chmod 600 ~/.ssh/*;
The following terminator layout ([download id=”4658″]) opens 3 different tabs, the first two tabs contain only one terminal each and the third one has 4 terminals in a 2×2 matrix.
Each of these tabs have their own custom name set and following each terminal has its name set to make it easier for the user to recognize the purpose of each one.
[download id=”4658″]
After opening these terminals, the configuration file, contains specific commands to be executed by each terminal, allowing you to automate a some trivial part of your day to day operations.
In this example, each terminal will navigate to a specific project or connect via ssh to some server, then it will perform some operation like performing a git pull and finally it will preserve the connection for you by starting a new bash instance to continue using that terminal.
Feel free to edit the layout and create a custom configuration for your tabs / the terminals and the commands.
config ([download id=”4658″]) file in your home user folder ~/.config/terminator/ with the one we providenautilus press Ctrl+H to view hidden files and folders if you cannot find the .config folder)terminator -l init;If you want to create an alias for this command:
Open .bashrc file at your home user folder and add the following
alias my-init="terminator -l init"
For any new terminal in terminator, executing my-init will spawn a new window of terminator that has all the configuration from the file loaded into it.
[global_config]
[keybindings]
[layouts]
[[default]]
[[[child1]]]
parent = window0
type = Terminal
[[[window0]]]
parent = ""
type = Window
[[init]]
[[[child0]]]
fullscreen = False
last_active_window = True
maximised = True
order = 0
parent = ""
position = 0:26
size = 1918, 1002
title = /bin/bash
type = Window
[[[child1]]]
active_page = 0
labels = www, MA, all other, dev logs, staging logs, live logs
last_active_term = d3c317d7-964a-4625-96d0-39deb5166072, 93ce7874-059e-4794-b337-7b640654a3d6, db090e6f-07e4-431e-ad86-a8b6cb965b5e, 906a5f4d-a3af-4da8-8385-673b132e7edd, 1b48b3b9-216c-470b-be53-ec1e8c6fdc0b, cb7d737c-a064-4e0e-ad5e-59c47d7bdd3b
order = 0
parent = child0
type = Notebook
[[[child11]]]
order = 3
parent = child1
position = 956
ratio = 0.500261643119
type = HPaned
[[[child14]]]
order = 4
parent = child1
position = 956
ratio = 0.500261643119
type = HPaned
[[[child17]]]
order = 5
parent = child1
position = 956
ratio = 0.500261643119
type = HPaned
[[[child4]]]
order = 2
parent = child1
position = 956
ratio = 0.500261643119
type = HPaned
[[[child5]]]
order = 0
parent = child4
position = 481
ratio = 0.500520291363
type = VPaned
[[[child8]]]
order = 1
parent = child4
position = 481
ratio = 0.500520291363
type = VPaned
[[[terminal10]]]
command = cd /vhosts/www.example.com/; git pull; bash
order = 1
parent = child8
profile = default
title = www.example.com
type = Terminal
uuid = db090e6f-07e4-431e-ad86-a8b6cb965b5e
[[[terminal12]]]
command = "ssh -t git 'cd vhosts/www.bytefreaks.net/ci_applications/registration_forms/logs/; ll; bash'"
directory = ""
order = 0
parent = child11
profile = default
title = WWW dev logs
type = Terminal
uuid = 4c08356b-b516-4286-8b6d-ba071f1394f3
[[[terminal13]]]
command = "ssh -t git 'cd vhosts/my.bytefreaks.net/symfony/var/logs/; ll; bash'"
directory = ""
order = 1
parent = child11
profile = default
title = MA dev logs
type = Terminal
uuid = 906a5f4d-a3af-4da8-8385-673b132e7edd
[[[terminal15]]]
command = "ssh -t web13 'cd /data/var/www/vhosts/staging-www.bytefreaks.net/htdocs/ci_applications/registration_forms/logs/; ls -la; bash'"
order = 0
parent = child14
profile = default
title = WWW staging logs
type = Terminal
uuid = 1b48b3b9-216c-470b-be53-ec1e8c6fdc0b
[[[terminal16]]]
command = "ssh -t web13 'cd /data/var/www/vhosts/staging-my.bytefreaks.net/htdocs/symfony/var/logs/; ls -la; bash'"
order = 1
parent = child14
profile = default
title = MA staging logs
type = Terminal
uuid = e26e94cd-855a-44ff-9c67-66b1c03bac56
[[[terminal18]]]
command = "ssh -t web13 'cd /data/var/www/vhosts/www.bytefreaks.net/htdocs/ci_applications/registration_forms/logs/; ls -la; bash'"
directory = ""
order = 0
parent = child17
profile = default
title = WWW Live logs
type = Terminal
uuid = 70466609-2d01-45d2-84b4-e377b111e540
[[[terminal19]]]
command = "ssh -t web13 'cd /data/var/www/vhosts/my.bytefreaks.net/htdocs/symfony/var/logs/; ls -la; bash'"
directory = ""
order = 1
parent = child17
profile = default
title = MA Live logs
type = Terminal
uuid = cb7d737c-a064-4e0e-ad5e-59c47d7bdd3b
[[[terminal2]]]
command = cd /vhosts/www.bytefreaks.net/; git pull; bash
order = 0
parent = child1
profile = default
title = www.bytefreaks.net
type = Terminal
uuid = d3c317d7-964a-4625-96d0-39deb5166072
[[[terminal3]]]
command = cd /vhosts/my.bytefreaks.net/; git pull; bash
order = 1
parent = child1
profile = default
title = my.bytefreaks.net
type = Terminal
uuid = 93ce7874-059e-4794-b337-7b640654a3d6
[[[terminal6]]]
command = cd /vhosts/www.michanicos.com/; git pull; bash
order = 0
parent = child5
profile = default
title = www.michanicos.com
type = Terminal
uuid = 2f204209-0c0b-4fab-b883-95f95f5d38e9
[[[terminal7]]]
command = cd /vhosts/www.etea.com.cy/; git pull; bash
order = 1
parent = child5
profile = default
title = www.etea.com.cy
type = Terminal
uuid = 6f801914-5225-4e1f-b54c-f48540274614
[[[terminal9]]]
command = cd /vhosts/www.ieee.org/; git pull; bash
order = 0
parent = child8
profile = default
title = www.ieee.org
type = Terminal
uuid = 3dbfe3a7-2e25-4e7d-bb02-dc4aeeeda47f
[plugins]
[profiles]
[[default]]
background_darkness = 0.8
cursor_color = "#ffffff"
foreground_color = "#ffffff"
OpenSSH is a freely available version of the Secure Shell (SSH) protocol family of tools for remotely controlling, or transferring files between, computers.
To install the openssh-server on an Ubuntu, you need execute the following command as root or using sudo:
apt-get install openssh-server -y;
To disable the ssh service, execute the following command as root or using sudo:
systemctl disable ssh;
To enable the ssh service, execute the following command as root or using sudo:
systemctl enable ssh;
To stop (or deactivate) the ssh service, execute the following command as root or using sudo:
systemctl stop ssh;
To start (or activate) the ssh service, execute the following command as root or using sudo:
systemctl start ssh;
To check the status of the ssh service, execute the following command as root or using sudo:
systemctl status ssh;
In a nutshell:
enabled is a service that is configured to start when the system bootsdisabled is a service that is configured to not start when the system bootsactive is a service that is currently runninginactive is a service that is currently stopped and may be disabled, but it can be started and become activeIn much more detail:
systemd provides a dependency system between various entities called “units” of 12 different types. Units encapsulate various objects that are relevant for system boot-up and maintenance. The majority of units are configured in unit configuration files, whose syntax and basic set of options is described in systemd.unit(5), however some are created automatically from other configuration, dynamically from system state or programmatically at runtime. Units may be “active” (meaning started, bound, plugged in, …, depending on the unit type, see below), or “inactive” (meaning stopped, unbound, unplugged, …), as well as in the process of being activated or deactivated, i.e. between the two states (these states are called “activating”, “deactivating”). A special “failed” state is available as well, which is very similar to “inactive” and is entered when the service failed in some way (process returned error code on exit, or crashed, or an operation timed out). If this state is entered, the cause will be logged, for later reference. Note that the various unit types may have a number of additional substates, which are mapped to the five generalized unit states described here.
— From man systemd
Recently, we’ve setup an Ubuntu server behind CloudFlare that needed to listen for SSH connections.
Unfortunately, CloudFlare does not allow connections to the default SSH port which is 22.
So, to achieve what it was needed we either had to change the port that the SSH service was listening to or add an additional port.
We decided to go with the option of listening to multiple ports for SSH connections, this way users that were also behind the CloudFlare CDN could still continue to use their SSH clients without being forced to define the connection port manually.
The port listening setting is available in /etc/ssh/sshd_config, using sudo we edited the file with a text editor and searched for the following lines:
# What ports, IPs and protocols we listen for Port 22
Right after the line that contains Port 22, we added another line for the new port (to see the list of all available open ports on CloudFlare, check this post)
And the file became as follows:
# What ports, IPs and protocols we listen for Port 22 Port 2053
Afterwards, we restarted the SSHD service to apply the changes by executing the following command by using sudo:
systemctl restart ssh;
