Servers Environment

Server Vs. Workstation workstation, which is dedicated to a single customer, multiple customers depend on a server. A server may have hundreds, thousands, or millions of clients relying on it. Servers are expected to last longer than workstations, which also justifies the additional cost. Server hardware has different features. They typically have maintenance contracts, disk-backup systems, OS, better remote access, and servers reside in the controlled environment of a data center, where access to server hardware can be limited.

Buy Server Hardware for Servers Systems sold as servers are different from systems sold to be clients or desktop workstations. (Short Term) Some of the Server features: Extensibility. Servers usually have either more physical space. load-balancing, automated fail-over, and similar capabilities. More CPU performance. multiple CPUs for pre-fetch, multi-stage processor checking, and the ability to dynamically allocate resources among CPUs. (CPU Speed, I/O can affect) High-performance I/O SCSI or RAID disk drives instead of IDE Upgrade options. Servers are often upgraded, rather than simply replaced. (More CPU). Rack mountable Space, Cooling No side-access needs All cables should be on the back, and all drive bays should be on the front. EASE High-availability options hot-swap components Management options Remote access to activate, Sensors

Servers in the Rack

Choose Vendors Known for Reliable Products Some vendors cut corners by using consumer-grade parts; other vendors use parts that meet MIL-SPEC1 requirements. Some vendors have years of experience designing servers. (Improvement, repair service, while Others not). Environments can be homogeneous or heterogeneous. Talk with other SAs. Communities: The System Administrators’ Guild (SAGE) ( League of Professional System Administrators (LOPSA) (

Understand the Cost of Server Hardware vendors have three product lines: Home (based on the advertised price) Business a(focus on total cost of ownership, 50,000/5,000) Server (focus on having the lowest cost per performance metric: file server web traffic online transaction processing (OLTP) aggregate multi-CPU performance cost more for other reasons, too. (chassis) A more valid argument against such a purchasing decision might be that the performance being purchased is more than the service requires. Performance is often proportional to cost, and purchasing unneeded performance is wasteful.

All machines eventually break. variety of maintenance contract options: (on-site service with a 4, 12 and next day response.) Consider Maintenance Contracts and Spare Parts

Scenarios for picking appropriate maintenance contracts: Non-critical server. CPU server that is one of many, (1, or 2 day response time, or no contract needed) Large groups of similar servers. The cost of the spares kit is divided over the many hosts. (Local Staff) Controlled introduction standardize for a set amount of time on a particular model or set of models that share a spares kit. At the end of the period, you might approve a new model and purchase the appropriate spares kit. Critical host it is too expensive to have a fully stocked spares kit, Common parts only. Large variety of models from same vendor. having an on-site technician, (Large Site) or Spare part depot in or near site. Or the technician remain for some time each day or available on phone. Highly critical host duplicate machine ready to be swapped into place. ( Costly) for Non technical site.

Trade-off between stocking spares and having a service contract. Stocking your own spares may be too expensive, (Sol: diagnostic Service contracts) easiest way to diagnose something is to swap in spare parts until the problem goes away (Difficult, need to train people). At critical time, SA discovers that a critical host is not on the service contract. (Sol: repaired on good faith). Good practice to review the service contract, at least annually if not quarterly. If no contract then: Make Inventory system have the person responsible for processing purchases should fix a common problem caused by warranties (12 Month etc., most venders required service contract to be purchased at the time of buying) Cross-shipped parts (send bad ones back to take new), requires returned merchandise authorization (RMA). The vendor generally gives the customer an RMA number for tagging and tracking the returned parts. (some on time delivery some not).  faster repair times( Buy spare part kit consist of complete parts, less costly then redundant server)

Maintaining Data Integrity Servers have critical data and unique configurations that must be protected. Workstation usually store their data on servers, which eliminates the need for backups. If a workstation’s disk fails, the configuration should be identical others, therefore can be recreated from an automated install procedure. But Local settings and installations cannot be recreated. In Windows (Completely Not) In UNIX (Some local files can be recreated)

Put Servers in the Data Center Servers should be installed in an environment with proper power, fire protection, networking, cooling, and physical security. It is a good idea to allocate the physical space of a server when it is being purchased. (Mark the place for rack). After assembling the hardware, it is best to mount it in the rack immediately before installing the OS and other software. (During test with dummy users Heavy load,No UPS, no AC). Some entire companies aren’t large enough to have data centers. However, everyone should have a designated room or closet.

Client Server OS Configuration Servers don’t have to run the same OS as their clients. Servers can be completely different, completely the same, or the same basic OS but with a different configuration. Single-function network appliances often have a mini-OS that contains just enough software to do the one function required, such as being a file server, a web server, or a mail server. When loading Solaris 2.x, you can indicate that this host is a server, which means that all the software packages are loaded, because diskless clients or those with small hard disks may use NFS to mount certain packages from the server.

Provide Remote Console Access Servers need to be maintained remotely. In the old days Server has own Keyboard, Displays etc. (More Space occupied) A KVM switch is a device that lets many machines share a single keyboard, video screen, and mouse (KVM). You can save even more room by having one KVM switch per row of racks or one for the entire data center. You can save even more space by using IP-KVMs, from your laptop while connected by VPNed into your network from a coffee shop. Remote access has many benefits: No Person required in Data center Space preserved Many people cause to produce heat in data center Easy HACKING (Drawback)

Provide Remote Console Access Pictures