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IBM i5/iSeries Primer
By Ted Holt, Kevin Forsythe, Doug Pence, Ron Hawkins
MC PressCopyright © 2006 MC Press Online, LLC
All rights reserved.
Getting Up and Running
The i5 server needs a certain amount of space as well as a special environment. Both must be provided for a successful installation. The place where you install the server is typically known as the computer room, although the machine can, in theory, be installed anywhere.
Planning Physical Space
In most cases, you will have to make do with whatever space is available for the computer room in an existing building. Whether a building is in the planning stages or you have a choice among several rooms in an existing building, you should plan the location of your computer room carefully.
The Computer Room
The computer room doesn't have to be located near computer users because, in theory, users don't need access to the machinery. Users only need access to their own display stations and printers. However, you should consider placing the computer room somewhere in the administration area because information systems (or data processing) is usually considered an administrative department.
Computer Room Requirements
The computer room should have the following minimal attributes. The room should:
* Be large enough to contain the i5 processing unit, all racks, tape drives, the system console, the system printer, a desk, a chair, a bookshelf, and a filing cabinet or drawer pedestal. Ideally, room should be available for the uninterrupted power supply unit (UPS) that protects the machines from power surges, spikes, and power failures. The computer room should be large enough to provide room for all these units and plenty of walking space around the units. This walking space is required not only for easy access, but for easy maintenance. It is easy to make the mistake of allowing so little space that you have to walk sideways between the machines.
* Have its own power supply. For example, the room can have a different power line from the rest of the building to minimize the risk of power problems. You should insist on this feature even if your system is going to be protected with a UPS unit. The UPS unit is mandatory for all i5. Although many units include a built-in battery that can keep the system going in the event of a power outage, the more sophisticated UPS units also protect the system from irregularities in the power supply, such as spikes and surges.
* Have air-conditioning, with a thermostat that only you can control. This air-conditioning unit should have no effect outside the computer room. This "private" air-conditioning unit ensures that the computer room is kept at a temperature suitable for computer equipment. As a general rule, the air-conditioning thermostat should be set so that the air is kept around 70 °F. This temperature provides comfort for both the people and the machines. Humidity is also a major concern if you work in a place where humidity is high. An air-conditioning specialist can recommend a dehumidifier to keep the humidity at a reasonable level in the computer room.
* Have its own telephones. To work well, the computer room must have its own telephone extension. So that outside calls don't have to go through the switchboard, some companies provide the computer room with a direct line for incoming or outgoing calls. If you think this is a superfluous frill, think about the times when data processing has to stay working after regular office hours and needs to receive important phone calls (possibly from IBM). If your i5 server is going to communicate with the outside world, order your phone line sufficiently ahead of time. Some phone companies are slower than others in installing telephone lines.
* Have a facility called Electronic Customer Support (ECS), which is described in Chapter 33. ECS lets your system contact IBM electronically through a telephone line. The computer room, therefore, requires an additional telephone line for the use of ECS.
* Depending on the type of security you need to implement, you might want to consider having a lock on the door to the computer room so that only authorized personnel can enter. This isn't an idle request you make just to feel important. Implementing system security through passwords and object authorities is worthless if the system itself is within reach of unauthorized persons.
Although IBM says that carpets don't usually present a problem for the i5, you probably will want to remove all carpeting from the computer room. Static electricity accumulates in the bodies of people who walk on the carpet, and it is discharged when a person touches a metallic object — such as the computer. This discharge can damage the equipment and can give you quite a jolt.
The best kind of flooring you can provide for the computer room is a raised floor. Raised floors consist of independent square tiles that sit on metal beams and columns, usually raised about 1 ft (30 cm) from the real floor.
A raised floor gives you added protection against floods because the water will accumulate under it instead of on top of it. Flooding is not an unlikely event. Think of those fire-extinguishing sprinklers hanging from the ceiling and what would happen if they were activated. Of course, floods due to rain are not uncommon in some regions.
Leave It to the Specialist
Most details of the building of the computer room can (and should) be left to a specialist in such matters. This book doesn't attempt to offer guidance beyond the basics. Three other matters to consider are:
* Cabling. Should you use twinax, twisted pair, or other kinds?
* Fire Prevention. Have special extinguishers available, but you probably should not install sprinklers on the ceiling. Halon is a safe and effective fire-extinguishing system, but it is not environmentally sound.
* External Interference. Are large machines close to the computer room that might produce magnetic fields? Is there radio frequency (RF) interference from a nearby radio, television, or radar station?
Laying Out the Computer Room
Unless you are an architect or an engineer, drawing the components to scale on charting paper won't mean much. Instead, consider the following method.
First, draw the walls of the computer room on paper, using a scale that is easy to work with (such as 1 ft = 1 in, or 1:10 in the metric system). The scale should let you include the entire computer room on a single sheet of paper, yet occupy as much of the sheet as possible.
Next, cut rectangular pieces of cardboard (sized to the same scale) to represent the computer room components, such as the computer unit, the racks, the printer, the desk, and so forth. You can obtain the dimensions of the machines from IBM's Planning Guide or use a tape measure and jot down the machine sizes if they are available to you.
Play with the cardboard pieces by placing, shifting, and arranging them in different ways on the drawing of the computer room until you find an arrangement that seems to work well. Only you can be the judge of this.
Now comes the interesting part. Get some masking tape and stick it on the actual floor of the computer room, to delineate the objects as you laid them out with the cardboard mockup. No matter how good it looks on your scale model, there is nothing like reality. You should be able to tell now if your model will actually work out as well as you thought it would.
Repeat this process as many times as needed. It is a lot of work, but it saves you from having to shift the actual machines after they arrive to your computer room. Pushing little cardboard pieces is a lot easier than pushing a rack full of DASD units.
IBM's Part of the Deal
After you have completed all your planning and are ready for the actual installation, you should call IBM (or whatever company sold you your i5) to have them perform the actual installation.
While you wait for the technician to arrive, you can save time and effort by uncrating the machines yourself. Save all the packing lists and the uncrating instructions, and follow the instructions carefully. If some crates show visible damage, don't open them! Let the IBM technician see the damage.
Also, with the help of one or more co-workers, move the uncrated machines to the space you planned for them. You shouldn't attempt to move the machines alone; most of them are extremely heavy and you could injure your back. When the IBM technician arrives, the technician will be ready to start working on the installation by hooking the units together.
An IBM technician will arrive at your site and perform the actual hardware installation. The amount of time the installation takes will depend on the size and number of the machines.
The technician has a lot to do. Help by staying out of the way, but be available in case your assistance is needed. Keep all nonessential personnel out of the computer room while the installation is in process.
Part of IBM's deal includes ensuring that i5/OS is loaded onto your machine. i5/OS was probably loaded at the factory (which is good, because loading the operating system can take many hours).
The IBM technician is not responsible for the installation of other software (such as your application software) on your system. It's unfair to ask. You should call the company that sold you the software. If the software is complex (such as MAPICS or BPCS), the software company might send someone to your office to install the software for you or, at the very least, give you instructions on how to do it.
IBM's technician should not be asked to install and connect the peripherals (displays and printers, for example) to your system. In the first place, it's not the technician's job to do it. More important, newly connected display stations could give someone in your company easy access to the server (which is still unprotected). Keep your i5 confined to the computer room until you have had a chance to set up security.
IBM's technician might be able to help you with some large printers, such as the 6262, if the units have the IBM logo on them. If the printer is manufactured by another company, you should call the company that sold you the peripheral if you cannot install it yourself.
You Take Over
After the i5 server is installed and ready to go, it is time for you to take over the rest of the installation process. This section gives you some basic advice.
Do Not Connect Other Devices
You should resist the temptation (and pressure from other people in your organization) to connect the display stations and printers at this stage because it is still premature. Before doing that, you must set up security, subsystems, user profiles, and device descriptions (at the very least).
To justify your actions when people request to be connected at once, tell them that it is like moving into a new house that doesn't have water, power, carpeting, or even finished walls. You need time to finish the "house" before you let the new tenants move in.
Setting Up Security
Security is very important. The i5 provides five levels of security: 10 (no longer supported on new systems), 20, 30, 40, and 50 (in order of increasing security). When IBM finishes the installation, security is set to security level 40. This should be sufficient for most routine uses of the server.
Because a person must enter a user profile name (also called "user ID") and a password, which must have been set up beforehand, security level 20 allows you to control who can sign on to the system. Still, once a user signs on, there is no limit as to what he may do. The only way to control users when your system is at security level 20 is to provide them with a menu that does only what they need to do on the system, and give them limited capabilities so they cannot enter any commands at the command line provided by the menu. Limited capabilities can be assigned using the LMTCPB parameter of the Create User Profile (CRTUSRPRF) or Change User Profile (CHGUSRPRF) commands. These commands are explained in some detail in Chapter 13.
Security levels 30, 40, and 50 are similar in that they all require not only a user ID and password to sign on, but they cause the system to check authorizations whenever the user attempts to perform tasks on objects or resources. In addition, levels 40 and 50 prevent users from accessing system objects (such as internal programs) or doing anything without going through "proper channels." Although the difference between 40 and 50 is small, level 50 also prevents passing invalid parameter values to system programs.
To change your system security level, change the system value QSECURITY with the Change System Value (CHGSYSVAL) command, and then IPL the system. When the IPL is complete, your system will operate under the new security level. To change the security level to 50, do the following:
CHGSYSVAL SYSVAL (QSECURITY) VALUE('50')
ENDSBS SBS(*ALL) OPTIONS(*IMMED)
The first command changes the security level to 50. If you want to change it to 30 or some other value, replace '50' for the appropriate value. The second command ends all subsystems and prepares the system for the IPL performed by the last command.
Setting Up Device Descriptions
Device descriptions are objects that describe a device to the system. The word "object" means something different to the system than it does to you. An object is a section of disk storage that contains information, has a name, and is contained in a library. For a better description of libraries and objects, refer to Chapter 19.
To configure peripherals on the i5, you need to create a device description for every display station and every printer you plan to connect to the system. This configuration process can be performed at any time, even when users are actively using the system. Older midrange computers, such as the S/36, force you to IPL the system before a new device can be used. The i5 does not need an IPL; the new device becomes available immediately.
i5/OS is capable of configuring devices automatically, or it can let you do it manually. If you want to use automatic configuration, change system value QAUTOCFG to '1.' To disengage automatic configuration (so that you must configure devices manually), change that system value to '0.' You change the system value using the CHGSYSVAL command. For example, to activate automatic configuration:
CHGSYSVAL SYSVAL(QAUTOCFG) VALUE('1')
Automatic configuration has some obvious advantages. The most visible advantage is that you don't have to worry about it. All you do is plug in a new display or printer and turn it on, and i5/OS configures it and makes it available. Before you use automatic configuration, please consider the following disadvantages:
* The device must be connected and powered on before the system configures it. This can reduce your chances to control how the device is configured and who has access to it, because the system makes it available to users immediately.
* You have no control over the name given to the device. Under automatic configuration, the system uses generic and meaningless names such as DSP02 and PRT03, although you can change the system-generated name using the Rename Object (RNMOBJ) command. Devices can have names of up to 10 characters, which makes it possible for you to come up with names that mean something. If you decide to turn off automatic configuration, run the following command before you attach any other devices:
CHGSYSVAL SYSVAL(QAUTOCFG) VALUE('0')
Now go to Chapter 13 for instructions for the creation and maintenance of device descriptions.
Setting Up User Profiles
You must create a user profile for each person you want to have access to the system. The user profile is actually another system object that you can create and maintain. Chapter 11 has detailed information about creating user profiles, including guidelines about naming and organizing them sensibly.
Because your system ships with security level 40, no one can sign on to the system before you create a user profile for that person, unless that person knows about the user profiles provided by IBM (such as QSECOFR and QSYSOPR) and their passwords.
Excerpted from IBM i5/iSeries Primer by Ted Holt, Kevin Forsythe, Doug Pence, Ron Hawkins. Copyright © 2006 MC Press Online, LLC. Excerpted by permission of MC Press.
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