I’m a byobu user for a long time, I love it for many reasons. But this is just a quick tip for extreme users like me. I mean people who use byobu for local consoles with remote byobu sessions running on top of SSH, for instance.
When prefix key combinations has to be sent to the remote host we have to press “Control + a + a” and finally the command that we want to send to the remote systems. This is not comfortable many times. So, I modified my configuration file for changing the prefix when I want to send remote commands to the nested byobu.
This is going to work this way:
Control + a
as a prefix for local byobu session.
Control + b
as a prefix for remote byobu session
Take a look on this screen capture where you can see byobu status bars stacked.
If you find useful the configuration that I described the only thing that you have to do is modify the configuration file: ~/.byobu/keybindings.tmux
unbind-key -n C-a
set -g prefix C-a
set -g prefix2 F12
unbind-key -n C-b
bind-key -n C-b send-prefix
Do not expect something exception, or may be anything that nobody else has. Both services are very common and widely available on Internet but I usually have issues when I try to use them.
This is the same reason because I created https://url.joor.net, my own short URL service. Maybe you are asking yourself about which are the next two service that I created for myself; but I exposed to everyone on the Internet.
Firstly I’m talking about a service that returns your public IP address mainly focused to be used from a shell console, but also available by web.
curl -L ip.joor.net
And it only returns your IP address as a plain text, allowing you to do things so useful as assigning the IP address to a variable. Of course, if you access with your web browser is it going to work perfectly to.
Finally, I want to reference a file sharing service also oriented on being used in the console, but it works OK when you use the browser. IMHO, the WUI (Web User Interface) is too much basic and it will be nice if it was more basic user oriented. But the simplicity of the API is the most powerful value of this service and which it makes a Swiss knife in the console. I’m not going to say anything else about the service try it by yourself.
Usually, simple things are the best, in the case I want to recommend an FTP server for Windows. This is a really simple but super useful FTP server for Windows. I’m using in Windows 10 and it works perfectly. Configuration is done in less than 10″ and installation is not required, I love that. Super portable.
Don’t expect sophisticated options but the most useful and advanced ones are there. If you need something like that my recommendation is:
Reading time: < 1 minute
Sometimes when a container is running for a long time especially when docker logs command is called the logs dump is extra long and then a recurrent search on google for reminding how to truncate a file is mandatory for avoiding this repeating task this is the trick that it saves me from that uncomfortable long log dump.
I imagine you are used to using curl for many command line scripts, tests, and much more things. I did the same but some weeks ago I discovered HTTPie which is the best substitute that I’ve ever found for curl. Of course, it’s also available for a lot of Linux distributions, Windows, and Mac. But I used it with docker which is much more transparent for the operative system and easy to update. To be more precise I use next alias trick for using this tool:
alias http='sudo docker run -it --rm --net=host clue/httpie'
When we have a file with a ‘dd’ of a full disk and we want to mount a partition of that disk, we have to use an offset for jumping to the beginning of the partition that we want to mount.
Using ‘fdisk’ command we can find the partitions of that disk copied inside a file.
fdisk -l FILE_WITH_DISK_INSIDE
Once partition table is shown there is a column called ‘Start’ using the corresponding number in this column for the partition that we want we can obtain the offset required for our mounting point. Reasoning behind that is multiply start sector per number of bytes per sector.
# OFFSET = START * 512
mount -o ro,loop,offset=OFFSET FILE_WITH_DISK_INSIDE /mnt
I hope thanks to this technical note next time that I forget how to get the offset I find it fastly.
If you don’t want to do that manually, there is a small tool called losetup which maps the partitions of a disk image on a file.
# example, attaching partitions to loopback devices
losetup -P /dev/loop0 DISK_IMAGE
# just mount the devices now, they are /dev/loop0pX where X is the number of the partition
# dettach this assignament:
losetup -d /dev/loop0