OneSIS

oneSIS is an open-sourced software tool developed at Sandia National Laboratories aimed at easing systems administration in large-scale, Linux cluster environments.

Why oneSIS?

Typical in today's corporate-computing environment, one will find teams of systems administrators working on scores of servers. A sysadmin can easily become bogged down by all the details of managing a large-systems environment. On one side, they may have to deal with the duplication of effort involved with standard repetitive tasks that are part of the job (ie. systems installation and deployment); on the other, become inundated with requests from a large group of users. As the pool of resources and users grow, this manual method of system administration fails to scale adequately. The high-performance computing (HPC) market epitomizes this considering that large-computational clusters can grow to sizes of 4000+ nodes and pools of power users who have varying needs.. For example, Suzie may want the sysadmin to allocate some nodes to do compare MPQC runs against different variables: she requests nodes 1-10 with the 2.4 Linux kernel and nodes 11-20 with the 2.6 kernel; but out of the latter, nodes 16-20 must use the OpenIB InfiniBand stack. This is just Suzie; the sysadmin must still deal with the remaining 3980+ nodes and twenty other users waiting for resources.

As demonstrated by the simple Suzie example, a sysadmin can have a lot of work cut out for him/herself. Enter [http://onesis.org oneSIS] . This open-sourced tool was designed by a systems administrator to ease the plight of the systems administrator. The official tag line for oneSIS is that it is "a thin, role-based Single Image System for scalable cluster management." oneSIS is a simple and highly extensible method for deploying and managing one or more root images of supported Linux distributions into a master image capable of being used as the root of diskless nodes. A single image can serve thousands of nodes.

About oneSIS

To begin using oneSIS, a few settings in the computing infrastructure have to be enabled, such as DHCP, PXE, and NFSroot. A quick HOWTO is located [http://onesis.org/NFSroot-HOWTO.php here] . Once those details are out of the way, the sysadmin can begin the process of determining which machine will serve as the source for the image that will eventually be deployed to the remaining machines in the cluster. Instead of going through all of the details of creating images, defining classes, and the like on this site, please visit [http://onesis.org the oneSIS HOWTO] for more information.

One of the easy-to-use conventions of oneSIS is that all configuration settings for all nodes within a cluster are controlled by a single file on the master node, "/etc/sysimage". This file is used to list the machines in the cluster, define which machines belong to what class, and explains which classes boot which images from the NFSroot server and how their configuration settings differ. Changes applied to the master images appear instantly to the nodes using said images. Changing a node to boot into a different image only requires a quick modification to /etc/sysimage and a reboot of the target client. Since oneSIS was designed with the Linux-systems administrator in mind, users will not find proprietary-GUI frontends here; all the tools to image a box, copying root-images, converting diskless machines diskfull, etc are accessible exclusively through the command line interface (CLI). The goal is to let Linux systems administrators feel at home with the typical CLI tools they're already use to.

OneSIS benefits include:
*Overall system complexity and administration overhead is reduced.
*Potentially more stable and secure environment because sysadmins concentrate on hardening single images.
*Images can be deployed in diskless and diskfull environments.
*Uses standard tools and settings found in any Linux distribution and the open Linux kernel source.
*Scalability.
*Possibilities for load balancing and failover support.

External links

* [http://oneSIS.org oneSIS Project Home]
* [http://www.sandia.gov Sandia National Laboratories]