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Linux AuFS Examples: Another Union File System Tutorial (UnionFS Implementation) AuFS stands for Another Union File System. AuFS started as an implementation of UnionFS Union File System. An union filesystem takes an existing filesystem and transparently overlays it on a newer filesystem. It allows files and directories of separate filesystem to co-exist under a single roof. AuFS can merge several directories and provide a single merged view of it. AuFS is used in many of the opensource projects like, Slax, Knoppix, and many other live CD and live USB distributions. On Debian based systems, for example on Ubuntu, do the following to install aufs. # apt-get install aufs-tools Example 1 – Understanding How AuFS Works This example shows how to mount two directories of a same filesystem. # mkdir /tmp/dir1 # mkdir /tmp/aufs-root # mount -t aufs -o br=/tmp/dir1:/home/lakshmanan none /tmp/aufs-root/ The first two commands created 2 new directories.

The mount command, specifies it is going to union mount “/tmp/dir1″ and /home/lakshmanan” under “/tmp/aufs-root”. In this example: LXC. Translation(s): none Linux Containers (LXC) provide a Free Software virtualization system for computers running GNU/Linux. This is accomplished through kernel level isolation. It allows one to run multiple virtual units simultaneously. Those units, similar to chroots, are sufficiently isolated to guarantee the required security, but utilize available resources efficiently, as they run on the same kernel. For all related information visit : Full support for LXC (including userspace tools) is available since the Debian 6.0 "Squeeze" release. Current issues in Debian 7 "Wheezy": You can also read some sub pages : LXC/Squeeze-Backport Installation Install required packages aptitude install lxc Install optional packages aptitude install bridge-utils libvirt-bin debootstrap Prepare the host Add this line to /etc/fstab (Do not do this on jessie with systemd, since it mounts cgroup.

Cgroup /sys/fs/cgroup cgroup defaults 0 0 mount /sys/fs/cgroup Check kernel configuration : Use: Debian Virtualization: Back to the Basics, part 3 | l3net – a layer 3 networking blog. The traditional Linux security model starts with file permissions. The model lets the kernel decide whether or not a process may access a resource based on permissions set as part of the filesystem. The coarse-grained granularity of this model often causes Linux processes to have too many rights.

If more granularity is needed, one has to resort to adding security related code into the program source. This series of articles is about Linux namespaces, a lightweight virtualization technology implemented in Linux kernel. Security at this level is always reactive. The same effect can be achieved on the cheap using Linux namespaces.

Network setup Configuring the host On the host, I run the following script: The script creates br0 bridge interface, enables routing, and configures the firewall. Configuring the container I create the container using clone() system call. I compile the program, start it as root, and verify I have only my bash session running in the container: # gcc -o jail main.c # . Install LXC + Web Panel on Ubuntu 13.04 w/NAT - Tutorials and Guides - vpsBoard. Kicking off my new blog,, with a guide for something that I have enjoyed recently. I know some other hobbyists here might enjoy the experiment in something they may not have done before. So I thought I'd share.

Sometimes OpenVZ is more than I want on a dedicated server. Sometimes I want a new kernel. LXC is container based "virtualization" that provides a native performance alongside the host operating system, much like OpenVZ does. Additionally, sometimes I want to separate the environment which houses my individual services but I don't necessarily need a bunch of IPs. Here is a look at the web based administration panel that you will be working with. On a fresh installation of Ubuntu 13.04, run the following command: apt-get update && apt-get -y upgrade && apt-get -y install lxc After this finishes, it's time to install LXC Web Panel. wget -O - | bash Username: admin Password: admin [one] - Port to forward to the container.

Overlayfs | Padgeblog. Docker has been a great advancement for mass consumption of linux based containers. The maturation of the virtual machine boom that has been happening since the early 2000’s led to mass acceptance and deployment in public and private clouds. To be sure, asking for bare metal today can be seen as a faux pas without some well-defined use case (like super high IO). So, now that folks have accepted that slices of CPU, memory, and disk are good enough through well-known hypervisors (kvm, esxi, xen) for most workloads, taking the next step to containers will not be that big of a leap.

Except that now it is more common to run containers on VMs than bare metal. So now we get a slice of a slice of a slice of resources! Virtual machines are just what their name implies: full machines that are virtualized. This means they have virtual hardware that virtually boots an OS kernel and mounts a filesystem. Boot or Start? Let’s compare boots of CentOS Linux on virtual machines versus containers: Lightweight Virtualization: LXC containers & AUFS. Conteneur LXC + NAT [Bearstech Blog] LXC/SimpleBridge. Translation(s): none This page includes examples of a bridged or routed network provided by the host.

Alternatives to this network setup for containers can be found on the LXC main page. Host device as bridge Features: persisted in host's /etc/network/interfaces the container's veth virtual ethernet interface can share the network link on the physical interface of the host (eth0). So the container resides on the same ethernet segment and talks to the same dhcp server as the host does. Requires bridge-utils package. Edit the host's /etc/network/interfaces in this form: Restart networking: /etc/init.d/networking restart The network section in the container's config (stored on the host in /var/lib/lxc/containername/config) may look like this Completing the example above, the container's /etc/network/interfaces may be edited to look like this auto eth0 iface eth0 inet dhcp #iface eth0 inet static # address <container IP here, e.g.> # all other settings like those for the host References.

Setting up LXC containers in 30 minutes (Debian Wheezy) UpdateVagrant has an LXC plugin that allows you to run containers instead of VMs in an almost transparent manner. Most of this guide still applies if you need to setup the networking for your containers or enable cgroups. Why LXC? So I'm doing web development, and I'm using Debian Wheezy as my development environment, which doesn't have the same version of software than stable, which is what we usually use as target servers.

I used to use chroots for this, but I found them painful to manage, especially when running daemons on the same ports than on the host machine. People like to use virtualization for this, such as VirtualBox (esp. with Vagrant) but I didn't want that since it forces you to start a whole virtual machine every time you want to develop. Running a virtual machine is quite a heavy process and they constantly use resources even if they don't do anything.

The main drawback of using LXC is that you can only run systems that support the same kernel as your host. Mount it: Advanced networking - Docker Documentation. Estimated reading time: 15 minutes This section provides an overview of Docker’s default networking behavior, including the type of networks created by default and how to create your own user-defined networks. It also describes the resources required to create networks on a single host or across a cluster of hosts. Default Networks When you install Docker, it creates three networks automatically. You can list these networks using the docker network ls command: $ docker network ls NETWORK ID NAME DRIVER 7fca4eb8c647 bridge bridge 9f904ee27bf5 none null cf03ee007fb4 host host These three networks are built into Docker. The bridge network represents the docker0 network present in all Docker installations.

The none network adds a container to a container-specific network stack. Note: You can detach from the container and leave it running with CTRL-p CTRL-q. The host network adds a container on the host’s network stack. The none and host networks are not directly configurable in Docker. LXC, la solution de virtualisation légère - Choix-Libres : Web log d'un utilisateur/administrateur GNU/Linux. Si comme moi vous aimez bien tester différents outils ou services GNU/Linux sans encombrer votre machine réelle, la solution de virtualisation par container LXC pourrait grandement vous aider. Voici les quelques avantages de cet outil : Optimisation de l'utilisation de votre machine en hébergeant plusieurs configurations systèmesSécurisation de vos process en les mettant à l'abris dans un "chroot amélioré".Facilité d'installation car l'outil est intégré au noyau Linux.Avoir sous la main un autre GNU/Linux sans manger toute vos ressources CPU Cet article n'a pas d'autre prétention que de me servir de bloc-note lors d'une prochaine réinstallation et ajouter une ressource française sur le sujet.

Pour l'installer sous Debian : Si besoin ajouter le système de paramétrage CGROUP à votre liste de points de montage dans votre fichier etc/fstab (vérifiez si la ligne suivante est déjà présente): cgroup /sys/fs/cgroup cgroup defaults 0 0 aptitude install bridge-utils aptitude install lxc pacman -S netcfg. HA Cluster with Linux Containers based on Heartbeat, Pacemaker, DRBD and LXC - Thomas-Krenn-Wiki.

The following article describes how to setup a two node HA (high availability) cluster with lightweight virtualization (Linux containers, LXC), data replication (DRBD), cluster management (Pacemaker, Heartbeat), logical volume management (LVM), and a graphical user interface (LCMC). As a result you will get a very resource- and cost-efficient shared-nothing cluster solution based completely on Open Source. Ubuntu 12.04 LTS is used as operating system. The cluster is operated in active-active mode in the sense of resources are running on both nodes but without sharing resources with a cluster filesystem.

This utilizes both servers and does not degrade one server to a hot-standby only system. The presentation from Linuxcon Europe 2012 gives further details about this topic: Event-News: LinuxCon Europe 2012 Disclaimer: This HOWTO is intended for advanced Linux users that are able to use the command line. Hardware OS Installation Here is the resulting Disk layout as shown by "lsblk": Créer des serveurs virtuels Debian 7 Wheezy avec LXC sur un dédié OVH Kimsufi | Blaise Thirard. (Dernière mise à jour : 19 février 2015) Présentation de LXC Tout comme Linux-VServer et OpenVZ, LXC est une solution de virtualisation de type isolateur. Cette solution permet la virtualisation par container au niveau du noyau.

LXC est très récent et remplace Linux-VServer et OpenVZ. Aussi, LXC est dès à présent intégré au noyau, ce qui n’a jamais été le cas des deux solutions citées précédemment. L’isolateur tire avantage de la possibilité, unique sous UNIX et Linux, de partager le noyau avec d’autres processus du système. Un programme, ensemble de programmes ou système dans le cas de virtualisation à noyau partagé fonctionnant dans un environnement chroot est protégé en faisant croire au système emprisonné qu’il fonctionne sur une machine réelle avec son propre système de fichiers. Cette solution est très performante du fait du peu d’overhead puisque les environnements virtualisés se partagent le code du noyau. Notes Compilation du nouveau noyau Linux Si screen n’est pas déjà installé : . Sans titre. Les Linux containers (lxc) sont une solution d’isolation ou de virtualisation (selon l’utilisation) à l’instar des Jails BSD.

Contrairement à d’autres solutions similaires (vserver ou openvz) sous Linux, les lxc ne nécessitent pas de patch du noyau car faisant directement partie de la branche principale du développement du noyau. Même si lxc est jeune (donc souffrant d’un certain nombre de bugs), il s’agit d’une solution déjà fonctionnelle. Je vais décrire ici l’installation et la configuration de lxc sur une Debian Squeeze disposant d’une seule interface avec une IP publique (comme sur un serveur dédié quoi).

Préparation du système On installe d’abord lxc et debootstrap : # apt-get install lxc debootstrap Il nous faudra aussi créer un bridge lié à une interface dummy : # apt-get install bridge-utils# modprobe dummy Ensuite il faut créer un bridge. Pour charger cette nouvelle configuration : # /etc/init.d/networking restart Préparation des cgroups Pas très compliqué : Création d’un container par.

Running LXC containers with Debian - Tutorials and Guides - vpsBoard. My love to LXC started again after this great post from jarland about LXC and Ubuntu. Ubuntu (latest stuff) and LXC are nice partners and play well. The web-based GUI is done in the right way. But basically you do not need the GUI and you do not need Ubuntu to use LXC. My tutorial today will show the basic low-end consolish Debian way to work with LXC.

So what is LXC? They say: Quote Current LXC uses the following kernel features to contain processes: Kernel namespaces (ipc, uts, mount, pid, network and user) Apparmor and SELinux profiles Seccomp policies Chroots (using pivot_root) Kernel capabilities Control groups (cgroups)As such, LXC is often considered as something in the middle between a chroot on steroids and a full fledged virtual machine. Licensing: And how can I work with it under Debian on a KVM? Next thing is enabling the cgroups: nano /etc/fstab #Add this line at the end cgroup /sys/fs/cgroup cgroup defaults 0 0 After that following command should show that everything is fine:

12.2. Virtualization. There are multiple virtualization solutions, each with its own pros and cons. This book will focus on Xen, LXC, and KVM, but other noteworthy implementations include the following: Xen is a “paravirtualization” solution. It introduces a thin abstraction layer, called a “hypervisor”, between the hardware and the upper systems; this acts as a referee that controls access to hardware from the virtual machines.

However, it only handles a few of the instructions, the rest is directly executed by the hardware on behalf of the systems. Let's spend some time on terms. Using Xen under Debian requires three components: The hypervisor itself. In order to avoid the hassle of selecting these components by hand, a few convenience packages (such as xen-linux-system-686-pae and xen-linux-system-amd64) have been made available; they all pull in a known-good combination of the appropriate hypervisor and kernel packages. . # mv /etc/grub.d/20_linux_xen /etc/grub.d/09_linux_xen # update-grub Voilà! 12.2. Virtualization.