Networking: A Beginner’s Guide Fifth Edition- P43 potx

Also, the annual impact of a lease is much lower than with a purchase, and leasing might make it easier to fit a particular server within your budget.. They also usually make it easy to

TIP Remember that it’s not really “cricket” to rely on the expertise of a particular supplier to help you select a server and answer any presales questions you have, and then to purchase the server from some mail-order supplier with a slightly lower price Try to be fair in your dealings You should not abuse vendors with higher support capabilities in this fashion; if you do so, they might not be around to help you with after-sales issues that arise, or to help you with future purchases This is not to say that you should pay a lot more for a piece of hardware from such vendors—just take into account the vendor’s level of service when you evaluate different price quotes, and remember that price isn’t everything

Depending on your company’s financial practices, you might want to consider leasing a server Doing so brings you several benefits First, leasing conserves your company’s cash Instead of shelling out $20,000 all at once, you can pay for the use

of the server over time Also, the annual impact of a lease is much lower than with a purchase, and leasing might make it easier to fit a particular server within your budget Leases also have a hidden benefit: They force you to consider whether to replace a server at the end of the lease term (usually three years) They also usually make it easy

to return the server to the leasing company and then lease a new server with which you can move forward In the end, you pay about as much for leasing as buying (all things considered), and leases can help discipline a company to keep its computer equipment relatively current The only drawback to leasing is that you must have enough time

to replace the server at the end of the lease, when you might prefer to do it several months before or after the lease is up Still, in some companies, the benefits of leasing far outweigh the disadvantages Discuss leasing with your financial department before ordering a server

Installing Servers

The actual practice of setting up a server is mostly specific to the server itself and the NOS that you plan to use In subsequent chapters, this book describes basic installations

of Windows and Linux

When you set up a new server, remember to plan on extensively testing its hardware prior to implementing it While most servers are reliable right out of the box, the fact is that if some part of the server is going to fail, it almost always fails shortly after being set

up and used I prefer to test servers for at least a week, even before installing the NOS onto the server Most servers come with diagnostic software that you can configure to operate continuously—testing the system’s processor, video subsystem, disk surfaces, and RAM—and log any errors that crop up Right after pulling a server from its box and installing any components that you need to install, plan on putting the server into a diagnostic loop using its diagnostic software and letting it run those tests for as long as possible In no case should you test the server for less than several days (try to shoot for

a week of testing)

TIP It’s important to start testing a server immediately after it arrives Most vendors have different

replacement versus repair policies depending on how long you’ve had a piece of hardware

For instance, many vendors will simply replace a server with an entirely new one if a failure is

discovered in the first 30 days, but after that, they’ll go through the normal repair process If an error

does appear during testing, you’ll probably be more confident with a new server than going through

a repair process (Plus, the repair process will take more of your time for troubleshooting and such.)

After finishing the testing, you can install the NOS During this phase, pay careful

attention to any peculiarities of the server and to any error messages reported by the

NOS or the server during the installation process

You must resolve these errors fully prior to going live with the server In particular,

watch out for any intermittent messages, such as a message that there was a parity

error in the system’s RAM or an unexpected lockup of the server during installation

Even if those problems don’t recur, consult with the maker of the server (Be sure you

carefully write down any messages or other things that you notice if this happens.)

Servers have a tendency to fail at the most inopportune times, so make sure that you

have complete confidence in the server before making it available to users It might

make sense also to let the server run its production software configuration for several

days as an added test before putting it into use

In particular, make sure to have all potential NetWare Loadable Modules (NLMs),

Windows services and processes, or UNIX/Linux daemons running together as part

of the testing When you combine third-party software for these platforms, there

are numerous opportunities for bugs or incompatibilities that the vendors did not

anticipate (despite a NOS vendor’s stamp of approval)

Most server manufacturers have made it easy to install their server and to install

the NOS onto the server Companies such as HP and Dell even ship their servers with

special CD-ROMs that mostly automate the process of installing various NOSs onto the

server and also install any needed support files that the NOS needs to work optimally

with the server hardware Prior to installing a NOS onto a server, make sure to read

the server’s documentation carefully and to take advantage of any automated tools

provided by the server manufacturer

TIP The top-tier server makers (IBM, HP, and Dell, for example) maintain e-mail notification

systems that let you know about any new patches they release or any serious problems they have

with a particular model These e-mail services are extremely useful, so you should plan on signing

up for them immediately on receipt of any new server

Here’s something else to think about: Sometimes servers are built and then sit

around in inventory for several months before being sold Consequently, the server

might not come with the most current software Before installing the server, check the

maker’s web site for any updates that aren’t in your package and consider whether to

install those updates during your implementation process

Maintaining and Troubleshooting Servers

To do the best job of maintaining and troubleshooting servers, you need to take steps

to do two things: decrease the chance of failure and improve your chance of rapidly resolving any failures that do occur Problems are inevitable, but you can greatly decrease your odds of having them, and you can also greatly improve your chances of resolving

them quickly by taking steps before you actually have any problems.

To decrease the chance of failure, make sure to follow all the advice previously given: use reliable, tested servers and components You should also take these additional steps:

N Whenever possible, try to reduce the number of jobs that a server must do Although building a single server that will be a file and print server, a database server, an e-mail server, and a web server is certainly possible, you’re much better off (from an overall reliability standpoint) segregating these duties onto smaller, separate servers

N Set up a practice of frequently viewing the server’s error logs If the server NOS supports notification of errors (such as to a pager), consider implementing this feature Many failures start with error messages that might precede the actual failure by a few hours, so getting an early heads-up might help you keep the server running or at least enable you to resolve the problem at the best possible time

N If a server supports management software that monitors the server’s condition, make sure to install the software

N Most RAID arrays that support hot-swap of failed drives also require that the NOS have special software installed to support this feature fully Make sure that you install this software before any failures occur

N NOS software is among the most bug-free available, but it’s still true that there

is no such thing as completely bug-free software Over time, any NOS will eventually fail While many servers run for up to a year without requiring

a restart, you’re better off establishing a practice of periodically shutting down the server and bringing it back up again This practice eliminates small transient errors that might be accumulating and could eventually lead to a server crash, such as memory leaks in the NOS The best frequency for such restarts is monthly

CAUTION Make sure that you do a backup before shutting down the server and restarting it The greatest chance of hardware failure occurs when the system is powered back up again

It’s a good idea to make three good backups and test restorations prior to putting

a server into use It might seem redundant, but you never know when you might need

to restore your data, and it’s important to know that your backup and restoration

practices will function properly

You can also do some general things to improve your ability to resolve any server

failures rapidly The most important is to maintain for each server an extensive binder

(or file box), which I call a “rebuild kit.” This binder should contain the following:

N All purchase data for the server, including your purchase order and a copy of

the supplier’s invoice

N A printout of the server’s configuration Most servers’ setup programs can

generate a detailed list with all components and their versions HP’s Insight

Manager is great for this

N All software needed to rebuild the server completely from scratch This includes

the setup software for the server, the NOS software, device driver disks, and

any patch disks you need or have applied Remember to add to the box any new

drivers or patches that you get during the life of the server so that they will be

available

N Contact information for service on the server, including any extended warranty

contract numbers or other information that you need to get service

N Notepaper, for documenting all changes to the server’s configuration and any

error messages that appear Write all the information clearly, noting the date,

the time, and any other details that you (or someone else) might need to fix the

server if it fails

N A printout or document noting anything special about the server or how you

configured the disk drives, including NOS settings You need these settings if

you have to rebuild from scratch Knowing these settings might enable you to

recover the data on the server’s disks so that you don’t need to restore the data

from backup tape

CAUTION You need a strong backup plan for any server, with appropriate tape rotations and

regular tests of your ability to restore data from the tapes you make The goal is to never need to

use these tapes, but they give you an absolutely critical safety net if the server’s disks crash and

lose their stored data

Even if you’re the best computer troubleshooter in the world, you should plan on

working with the service department of your server’s manufacturer to troubleshoot

any problems Doing so can save you because the people in this department have

extensive databases available to them of the problems others have experienced

They also are familiar with the steps needed to help prevent data loss as you work

to troubleshoot the problem Troubleshooting a server on your own, no matter how

experienced and knowledgeable you are, is usually a mistake

Chapter Summary

When building a network, the one component you should pay the most attention to is the server While other parts of the network, like the wiring, network architecture, or workstations, are also significant, the server is the most likely component to experience trouble over time The server is the single component you must spend the most time managing Because of this, take extra care when selecting, implementing, and maintaining your servers If you take care of your servers, your servers will take care of you

The following chapter concerns network workstation computers and discusses the different requirements desktop computers have, how you should buy and manage them, and how to support them