Let’s assume you rendered your FreeBSD system unbootable.. Yeah, happens to the best, but how can you still copy the data stored on a ZFS to another machine? You probably just shouted RSYNC - but it’s not that easy.
You would need a FreeBSD live os (either on a USB pen drive or on a CD/DVD) and boot into that system. However, by default you do not have network, the ZPool is not mounted, there is no rsync and SSH is not running, and the live os is not writable, which brings another few issues…
This is a step-by-step how-to through all the obstacles. Just boot into your live os (get it from freebsd.org) and go on with the following…
By default your live system does not have networking setup correctly.
ifconfig to see if the network interface is up. If it’s not you can bring it up using:
(assuming your inteface is called em0)
If it is up, you need to configure it. When you’re using a DHCP server you can just ask for an IP address using:
Otherwise you need to configure the addresses manually:
Afterwards you should be able to ping other machines, such as
Mount the ZPool
Your ZPool won’t be mounted by default; you need to do it manually. To list all pools available on that machine just call:
This searches through the devices in
/dev to discover ZPools. You may specify a different directory with
-d (see man page for zpool).
To actually import and mount your ZPool you need to provide its name, for example:
This will import the ZPool
zroot. Moreover, the argument
-o altroot=/mnt will mount it to
/mnt instead of
/ and the
-f will mount it even if it may be in use by another system (here we’re sure it isn’t, aren’t we?).
Create some Writeable Directories
The next problem is, that you do not have permissions to write to
/etc, which you need to e.g. create SSH host keys etc.
However, that’s also not a big issue as we have the
unionfs filesystem! :)
UnionFS will mount a directory as an overlay over another directory.
Let’s assume you have some space in
$SPACE (maybe in the ZPool that you just mounted or on another USB drive), then you can just create a few directories:
and mount it as
unionfs to the root’s equivalents:
Now we can write to
/etc, while the actual changes will be written to
$SPACE/etc! Isn’t that a great invention?
Start the SSH service
/etc is writable we can start caring about the SSH daemon.
First, we need to configure it to allow root to login.
Add the follwing line to the
Then, we can start the ssh daemon using:
It will automatically create host keys and all the necessary things for a first start of SSH.
If that was successful, port
22 should now be open:
Set root Password
To be able to login you of course need to set a root password:
Aftwerwards, you should be able to login through SSH from any other machine. Go ahaed and give it a try!
Install and Run rsync
Almost there, but the freeBSD live image doesn’t come with
So we need to do it manually:
This will first tell us that not even
pkg is installed, but answering the question with
y it will automatically install itself.
And as everything is mounted as UnionFS, the stuff will actually be installed to
$SPACE/... instead of
However, you should now be able to do the rsync job from where ever you want :)
Never heard of that FlexNet thing, but according to Wikipedia it’s a software license manager. And we all know how this whole DRM thing just bugs us.. So it bugged me because the new system wouldn’t boot properly.. Other people having similar problems.
However, it seems impossible to force grub overriding this sector, but you may wipe it manually. In my case sector 32 was infected by DRM, so I did the following:
If that’s done Grub installs like a charm, the system booted again, and the admin was happy that another DRM thing died :)
As I’m working with Docker quite intensively it was about time to develop some tools that help me managing different tasks. Some of them have already been existing as functions in my environment or something, but now they are assembled in a git repository at GitHub.
The toolbox currently consists of the following tools:.
dclean cleans your setup
The Docker-Clean tool
dclean helps getting rid of old, exited Docker containers.
Sometimes I forget the
--rm flag during tests, and when I realise it there are already hundreds of orhpaned containers hanging around..
dclean without arguments removes all of them quickly.
dclean tool accepts a
-i flag which will clean the images.
It will prune all dangling images.
Dangling images are orphaned and usually not needed anymore.
dclean -i will remove them.
denter gets you into a containers
The Docker-Enter tool
denter beames you into a running Docker container.
Just provide the container’s name or CID as an argument to get a
/bin/bash inside the container.
denter will just call
/bin/bash by default.
So there is no magic, it’s just a shortcut..
You may overwrite the program to be executed by providing it as a second argument.
ps -ef in the container with the id
dip shows IP addresses
The Docker-IP tool
dip shows the IP addresses of running containers.
Without arguments it will print the IP addresses, names, and container ids of all running containers.
If your interested in the IP address of a specific container you may pass that container’s CID as an argument with
-c, just like:
This will show the IP of the container with id
dkill stops all running containers
The Docker-Kill tool
dkill is able to kill all running containers.
It doesn’t care what’s in the container, it will just iterate over the
docker ps list to stop all running containers.
As this is quite dangerous, it requires a
-f flag to actually kill the containers.
You may afterwards run the
dclean tool from above to get rid of the cadavers..
dupdate updates images
The Docker-Update tool
dupdate helps you staying up-to-date.
It will iterate over all your images and tries to pull new versions of that image from the Docker registry (or your own registry, if you have one).
By default, it will echo the images that have been updates and tells you which images cannot be found (anymore) on the registry.
You may pass the
dupdate to enable verbose mode and also get a report for images that do not have a newer version at the registry.
This way, you can make sure that all images are checked.
Similarly, you can pass
-s to enable silent mode and suppress messages about images that cannot be found at the registry.
You may also want to look at the Docker-Update tool?
This way, you’ll stay up-to-date with bug fixes etc.
You middle-click a few youtube videos and all start shouting against each other. You enter a website and it immediately slaps sound in you face. How annoying…
But there may be help.
about:config and set
trueto only play media that is also in the current tab an do not play the stuff from the background
falseto stop autoplaying of some of the media (doens’t work everywhere, not sure why..)
dom.audiochannel.mutedByDefaultsets the audio muted by default – essential for offices
plugins.click_to_playrequires a click to run plugins, such as flash (which you are anyway not using!)
However, I’m experiencing a problem with highlighted text in Okular, my preferred PDF viewer. When I highlight something in Okular the highlight-color (blue) is far too dark, the highlighted text isn’t readable anymore. I used to live with that, but it was quite annoying. Especially when you’re in a meeting/presentation and you want to highlight something at the projector. I just saw that problem occurring in Okular. Not sure why, but I honestly do not understand this whole desktop config thing – probably one of the reasons why I love i3 ;-)
Today, I eventually digged into the issue and found out
what’s the problem how to solve the problem.
Apparently, Okular uses a Qt configuration, that can be modified using the
Just install it (here for Qt4 applications):
When you run
qt4-qtconfig a window will pop up, as you can see in the figure on the right:
- Select a GUI Style that is not Desktop Settings (Default), e.g. Cleanlooks.
- Then you can click the Tune Palette… button in the Build Palette section.
- A second window will pop up. Select Highlight in the Central color roles section.
- Finally you’re good to select the hightlight color using the color chooser button! :)
Was a bit difficult to find, but the result is worth it! The figure on the bottom shows the new highlight color – much better.
I will probably never understand all these KDE, QT, Gnome, GTK, blah settings. Every environment does it differently and changes the configuration format and location like every few months. At least for me that’s quite frustrating…