Efficient and Reliable Filesystem Snapshot Distribution

Abstract: Linux is an portable operating system kernel devised by Linus Torvalds and it can be used in conjunction with other userspace utilities such as GNU to build a free and open-source operating system for a multitude of target applications. While Linux-based operating systems have made significant progress on the servers and embedded systems, there is still much room for improvement for workstations and laptops. Up to now Linux-based operating system deployment has been error prone, time-consuming process and usually specific to a particular distribution of Linux. Linux-based operating systems also have a reputation of being overly complex to set up for a novice computer user and even though there are now laptops available with pre-installed Ubuntu [1], installing Linux-based operating system on arbitrary device is troublesome due to lack of native support for certain hardware components. In this thesis Butterknife, a B-tree file system (Btrfs) and Linux Containers (LXC) based provisioning suite is presented. Butterknife can be used to significantly reduce deployment time of customized Linuxbased operating system. Butterknife makes use of LXC to prepare a template of the root filesystem and Btrfs snapshotting to save state of the template. Btrfs send/receive mechanism is then used to transfer the root filesystem to the target machine. Post-deployment scripts are then used to configure the root filesystem for particular deployment, optionally retaining hostname, domain membership, configuration management keys etc. Current implementation of Butterknife uses HTTP(S) and multicast for transport, and various peer-to-peer scenarios are discussed in the Section 6 – Conclusions and Future Work. In addition to provisioning, Butterknife makes use of Btrfs incremental snapshots to implement differential upgrades. This approach is especially attractive for mobile devices, embedded systems and Internet of Things, where software upgrades have to be delivered in a guaranteed manner. Butterknife brings additional value to already existing ecosystem by bridging gap between stock installation medium and configuration management.