A Blog of the ZHAW Zurich University of Applied Sciences
In a previous blog post, we showed how “bringing the code to the data” can highly improve computation performance through the active storage (also known as computational storage) concept. In our journey in investigating how to best make computation and storage ecosystems interact, in this blog post we analyze a somehow opposite approach of “bringing […]
What is active storage about? In most of the distributed storage systems, the data nodes are decoupled from compute nodes. Disaggregation of storage from the compute servers is motivated by an improved efficiency of storage utilization and a better and mutually independent scalability of computation and storage. While the above consideration is indisputable, several situations […]
(Part 1/3 – Installation – Part 2/3 – troubleshooting) This part of the tutorial describes how to setup a simple Ceph client using librados (for C++). The only information that the client requires for the cephx authentication is Endpoint of the monitor node Keyring containing the pre-shared secret (we will use the admin keyring) Install librados APIs On Ubuntu, […]
(Part 1/3 – Installation – Part 3/3 – librados client) It is quite common that after the initial installation, the Ceph cluster reports health warnings. Before using the cluster for storage (e.g., allow clients to access it), a HEALTH_OK state should be reached: cluster-admin@ceph-mon0:~/ceph-cluster$ ceph health HEALTH_OK This part of the tutorial provides some troubleshooting hints that I […]
Ceph is one of the most interesting distributed storage systems available, with a very active development and a complete set of features that make it a valuable candidate for cloud storage services. This tutorial goes through the required steps (and some related troubleshooting), required to setup a Ceph cluster and access it with a simple client […]
With this post we are going to start a new series on Distributed File Systems. We are going to start with an introduction to a file system that is enjoying a good amount of success: Ceph. Ceph is a distributed parallel fault-tolerant file system that can offer object, block, and file storage from a single cluster. […]
In a former article we spoke about testing High Availability in OpenStack with the Chaos Monkey. While the Chaos Monkey is a great tool to test what happens if some system components fail, it does not reveal anything about the general strengths and weaknesses of different system architectures. In order to determine if an architecture with 2 redundant controller nodes and 2 compute nodes offers a higher availability level than an architecture with 3 compute nodes and only 1 controller node, a framework for testing different architectures is required. The “Dependability Modeling Framework” seems to be a great opportunity to evaluate different system architectures on their ability to achieve availability levels required by end users.
As proposed in a former article different technologies must be evaluated in order to make the current MobileCloud environment suitable to High Availability (HA) requirements. The following article lists a basic evaluation of the different technologies that could be used. Basically there are four technologies which allow to build a reliable HA-infrastructure for OpenStack…