Linux servers on the job

The slim machines in the foreground of this photo, next to a rack of Sun servers, are some of the Linux systems deployed as servers in the SCD Computer Room. The six blue machines at the top of the rack are VA Linux 1120 systems. They are providing Domain Name Service (DNS) and user authentication (cluster of two), virus scanning of email attachments (cluster of two), email aliasing and mailing list services, and NetNews service. The gray machine below these is longs, a VA Linux 2240 system providing front-end services to NCAR supercomputing resources. The black machine below longs is freeswan, a Penguin Computing system that provides Linux VPN service, a secure access method for Linux systems outside the UCAR security perimeter.

For the types of services that they are suited to provide, Linux systems are growing in popularity around the world. There are many reasons why more Linux servers are being deployed in the SCD computer room.

The primary reason is that it is easy and inexpensive to expand the service as computing demands grow. When the demand on a server slows it down, additional servers can be added to share the load. Linux servers are also straightforward to deploy in a cluster configuration, providing redundancy and failover operation. Linux servers are cost effective, and there is a large and growing base of robust, inexpensive (or free) software applications that run on them.

Photo: Brian Bevirt/SCD