Server Systems Administration Types of Servers Small Servers

Server Systems Administration

Types of Servers • Small Servers – Usually are PCs – Need a PC Server Operating System (SOS) such as Microsoft Windows Server, Novell Net. Ware, LINUX • Large Servers – Usually use Workstation Servers – Usually run UNIX

Symmetric Multiprocessing (SMP) • PC or workstation can have multiple microprocessors • Work is shared among the microprocessors through symmetric multiprocessing (SMP) to increase overall speed • However, if you have N microprocessors, your server is not N times faster than a singlemicroprocessor server because of problems in assigning work evenly

RAID • Redundant Array or Inexpensive (or Independent) Drives – RAID controller controls multiple small inexpensive disk drives – Reads and writes in parallel for higher speed despite low-cost drives

RAID • Redundant Array or Inexpensive (or Independent) Drives – Information is stored redundantly – If one disk fails, lose no information – Drives may even be hot-swappable • Do not have to turn off computer to replace

Server Farms • In large sites, one server is not enough – Have several, even hundreds of servers – Called a server farm – Many PC servers may be more cost-effective than fewer workstation servers Server Farm

Server Farms • Load Balancing Approach – Router or other device sends requests to servers based on load

Server Farms • Server Clustering Approach – Act as a single server without an external load balancer

Server Farms • Reliability – If one server’s hardware fails, operation continues without interruption – However, software failures often take down all servers simultaneously

Server Configuration • When Server Operating System is Installed, it Must be Configured – Complex task with many steps, many of which require you to have conceptual knowledge – Requires training – Valuable skill

Ongoing Work • Server Systems Administration is Labor. Intensive on a Continuing Basis – Assigning and changing rights for users – Backup –…