Improve your remote SSH sessions with Byobu

Tutorial
Byobu Improve your remote SSH sessions
We can manually assign
which two or more
windows to enable here
Here you can see a screen
that has been split into two
vertically. We can also have
more splits if we like
At the bottom of the
window is a list of open
windows and the status of
the machine you are using
Improve your remote SSH
sessions with Byobu
Byobu is an
enhancement for
GNU Screen that
features lots of
powerful shortcuts
and is incredibly easy
to use. Here’s how to
improve your remote
SSH experience the
easy way…
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Byobu is a Japanese term for decorative,
multi-panel screens that serve as folding
room dividers. Byobu is also the name of a
project that enhances GNU Screen. If you have
used or regularly use the GNU Screen utility,
you might have an idea about just how much it
can help enhance your remote SSH sessions. It
gives you a lot more power and flexibility than
the regular Terminal window would otherwise.
The issue with Screen, though, is that it can be
a bit awkward to get to grips with – the polar
opposite of Byobu…
Advisor
Sukrit Dhandhania has spent several
years working professionally,
implementing several open source
tools for companies. During this
time he has evaluated, set up and
maintained various open source tools
for these firms
Resources
Byobu is an enhancement package for the GNU
Screen application https://launchpad.
net/byobu
01
Install Byobu on Meerkat
Getting Byobu is pretty simple, at least on
Ubuntu Linux. If you are using the latest release
of Ubuntu, which is Ubuntu 10.10 Maverick
Meerkat or better, you should be able to find
Byobu in the apt-get repositories. Launch the
Synaptic Package Manager, search for ‘byobu’
and install the package (Fig 1).
02
Install on others
If you are using another distribution of
Linux, check in its application repository to see if
there is a binary. If you are using another version
of Ubuntu Linux and you can’t find the app in the
apt-get repositories, you can use the following
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Improve your remote SSH sessions with Byobu
Use Byobu to enhance GNU Screen to give you more power and flexibility
TUTORIal
configuration. Hit F9 to load the tool’s
configuration module. This configuration
interface works as a textual menu. You can
navigate it by using the up and down arrows.
Hit the Tab button to move from one section to
another. Use the spacebar to select or deselect
an item. If you need help at any time, hit Enter on
the ‘Help -- Quick Start Guide’ option.
Fig 1 Install Byobu on Meerkat The Byobu installation process on Ubuntu Meerkat is very
simple indeed
method to install Byobu. Note: Replace the
term ‘UBUNTU_VERSION’ with the name of your
release, such as jaunty, intrepid or hardy.
# sudo bash -c “echo ‘deb http://
ppa.launchpad.net/byobu/ppa/ubuntu
UBUNTU_VERSION main’ >> /etc/apt/
sources.list”
# sudo apt-key adv --keyserver
keyserver.ubuntu.com --recv-keys
F430BBA5
03
Test Byobu
Execute the command ‘# byobu’ from
the Terminal window. You should see the window
change and look something like the screenshot
below. However, if you received an error stating
something like ‘Error: Can’t open slave tty /dev/
pts/1 -- Permission denied’, you will need to fix
some permissions. Execute the command ‘#
sudo chmod a+rw /dev/pts/1’. Change the 1 to
the number from the error message.
n What Byobu looks like at first launch, with
its default settings
04
The Byobu Interface
You will note that there is a colourful strip
of information being displayed at the bottom
of the Terminal window. This is part of the
enhancements that Byobu bring to the Terminal.
By default it displays some basic information like
the machine’s name and IP address, along with
a few statistics about the state of the machine,
such as the amount of RAM and CPU being
used. Here’s a more complete list of things that
Byobu can display in the strip at the bottom of
the Terminal screen.
1. Screen windows list
2. Battery status
3. CPU count
4. CPU frequencies
5. Current date/time
6. Disk space
7. EC2 cost
8. Fan speed
9. Hostname
10. IP address
11. Load average
12. Mail count
13. Memory available/used
14. Network transfer speeds
15. Temperatures
1. Processes running (count)
2. Users logged-in (count)
3. Wi-Fi quality
4. Updates available
05
Customise Byobu
n The Byobu application menu
06
Change the look and feel
The first set of customisations we’ll look
at will enhance the look and feel of the Terminal.
Byobu gives you a couple of options on this front.
You can change the background and foreground
colours being used in the Terminal. Enter the two
sections for picking colours, choose the colour
you like for each option and then hit the Apply
option. If you don’t like it, you can always return
to the menu and change the colour.
n Pick a colour to customise the look of your
Terminal windows
07
Status notifications
We’ve found the status notification bar at
the bottom of the screen to be immensely useful.
The fourth option in the Byobu config menu is to
configure what goes into this status notification
bar. Hit Enter on this menu option to start. Now
pick the info you want displayed constantly on
With so many more options to view
information, it is easy to customise Byobu’s
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Tutorial
Byobu Improve your remote SSH sessions
Fig 2 The new window You can see a list of windows in the status bar
your screen. Note that you do not want to go
overboard with your selection as it could be quite
distracting. Choose the Apply option when done.
presented with some options. You can pick which
shell you want to use for the window, you can give
it a name, you can choose from some presets,
and you can add it to your list of default windows.
Hit Apply to create a new window.
Moving between windows
09
The new window
the status bar
08
New window options
If you are familiar with using GNU Screen,
you might be aware of the powerful virtual
Terminal interface that it provides you with. You
can access this option in Byobu by selecting
the ‘Create new windows’ option. Here you are
Another very
interesting feature
makes it possible
to split the screen
into regions –
either vertically or
horizontally
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different operations going on in parallel
11
n Launch a new window through the menu
n Select the notifications you want to see in
n A horizontally split window with two
What happens when you hit Apply in the
previous step is that you are immediately taken
to the window that you just created. You can use
the F3 key to move around between windows that
you have created. You should be able to see a list
of the windows in the byobu status notification
bar as you create them (Fig 2).
10
Split the screen
Another very interesting feature makes
it possible to split the screen into regions. With
‘Ctrl-a S’ you can create a new horizontal zone.
This area will not contain anything at first, but
you can move the focus there with ‘Ctrl-a <tab>’
and then activate a window in this region with a
command to switch windows as ‘Ctrl-a N’. If you
prefer a vertical division of the windows, you can
use ‘Ctrl-a |’, which will do exactly the same thing
but by dividing the screen into two regions with a
vertical dividing line.
As you get comfortable with working
with multiple virtual windows, you will start
finding a need to be able to quickly switch
between windows, to toggle between them,
and even to be able to jump straight to a
particular window. Byobu has all these
options ready for you. Use ‘Ctrl-a n’ and ‘Ctrla p’ to switch to the next or previous window
in the list, by number, and ‘Ctrl-a #’, where
# is a number from 0 to 9, to switch to the
corresponding window. To get a full-screen list
of windows, use the combination, ‘Ctrl-a ” ’;
navigate this list with the arrow keys and pick
a window to activate by pressing Enter when it
is highlighted (Fig 3).
12
Name or rename a window
You can name or rename a window with
relative ease, even as you are using the window.
Hit the key combination of ‘Ctrl-a A’. You will see
a prompt where you can see the old name of the
window. Remove it and set your new name there.
Hit Save for it to get saved.
n Rename a window to make it easier to keep
track of it
13
Default windows
In a previous step we looked at the
process of creating a new window from the
Fig 3 Moving between windows A list of open windows
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Improve your remote SSH sessions with Byobu
Use Byobu to enhance GNU Screen to give you more power and flexibility
TUTORIal
h Move the cursor left by one character
j Move the cursor down by one line
k Move the cursor up by one line
l Move the cursor right by one character
0 Move to the beginning of the current line
$ Move to the end of the current line
G Moves to the specified line (defaults to the end
of the buffer)
/ Search forward
? Search backward
n Move to the next match, either forward or
backward
Byobu menu. There was an option there to
add the window to the default list of windows.
This is a list of windows that will get launched
by default. You can view and manage this list
by going to the ‘Manage default windows’
option in the menu. Here you can select the
windows you want launched when you launch
the Terminal.
16
Keyboard shortcuts
n Manage the list of windows you want
launched by default
14
Manual configuration
If you would like a bit more control over
the configuration of Byobu, you can access
the configuration files from the hidden folder
called .byobu under your home directory.
Here you will find a number of configuration
files such as the status file where you can
easily configure your preferred settings
manually (Fig 4).
Fig 4 Manual configuration The manual
configuration is a good option for advanced
users, offering extra control
15
Moving around
If you are familiar with the Vim or Vi text
editors, you will find the navigation shortcuts of
Byobu quite useful as they are pretty much the
same. Here is a list of a few of the most useful
movement keyboard shortcuts…
Here are some useful keyboard
shortcuts that you should familiarise yourself
with. Tools like Screen and Byobu add a great
deal of efficiency to your workflow. However,
if you are dependent on using the mouse for
menus, things might slow down a bit. Once you
are familiar with Screen/Byobu keyboard
shortcuts, you will see a noticeable change
in the speed and efficiency with which you go
about working on the Terminal interface.
F2 Create a new window
F3 Move to previous window
F4 Move to next window
F5 Reload profile
F6 Detach from this session
F7 Enter copy/scrollback mode
F8 Re-title a window
F9 Configuration menu
F12 Lock this Terminal
17
Launch Byobu by default
If you want Byobu to be activated
automatically every time you launch the
Terminal window, you will need to make a
change to the settings. Hit F9 after entering
the Byobu interface. You will be presented
with a menu. Choose the last option in the
menu. Hit Enter to toggle the option whether
to log into Byobu upon login or not. Then in
the gnome-terminal application, go to Edit>
‘Profile preferences’ and select the ‘Title and
Command’ tab. Check the ‘Run command as
login shell’ option (Fig 5).
In this article, we looked at a few of the
options that the wonderful tool Byobu gives
us. However, it is very difficult to cover all the
useful options. Therefore we strongly urge you
to spend some time reading the application’s
man page. It will greatly help you enhance
your workflow.
Fig 5 Launch Byobu by default Set Byobu as your default Terminal interface
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