Manuale d’uso / di manutenzione del prodotto SC41-5420-04 del fabbricante IBM
Vai alla pagina of 116
iSeries TCP/IP Configuration and Reference V ersion 5 SC41-5420-04 .
.
iSeries TCP/IP Configuration and Reference V ersion 5 SC41-5420-04 .
Note Before using this information and the pr oduct it supports, be sure to r ead the information in “Notices” on page 93. Fifth Edition (May 2001) This edition replaces SC41-5420-03. This edition applies only to r educed instruction set computer (RISC) systems.
Contents About TCP/IP Configuration and Reference (SC41-5420) ........ v Prerequisite and related information . . vii O p e r a t i o n s N a v i g a t o r ........... v i i How to send your comments ..... i x Summary of changes ......... x i Chapter 1.
IP Multicasting ............. 6 8 Multicast Application Programming Information 68 Multicast Restrictions .......... 6 8 Chapter 3. TCP/IP Performance .... 7 1 *BASE Pool Size ............. 7 1 TCP/IP Jobs .............. 7 1 TCP/IP Pr otocol Support Provided by IOP .
About TCP/IP Configuration and Reference (SC41-5420) This book contains information about configuring T ransmission Control Protocol/Internet Pr otocol (TCP/IP) and operating and managing your network. Most topics have been moved to the Information Center .
vi OS/400 TCP/IP Configuration and Refer ence V5R1.
Prerequisite and related information Use the iSeries Information Center as your starting point for looking up iSeries and AS/400e technical information.
viii OS/400 TCP/IP Configuration and Refer ence V5R1.
How to send your comments Y our feedback is important in helping to provide the most accurate and high-quality information. If you have any comments about this book or any other iSeries documentation, fill out the readers ’ comment form at the back of this book.
x OS/400 TCP/IP Configuration and Refer ence V5R1.
Summary of changes This is the fifth edition of TCP/IP Configuration and Reference . Most topics from the fourth edition of TCP/IP Configuration and Refer ence have been moved to the iSeries Information Center .
xii OS/400 TCP/IP Configuration and Refer ence V5R1.
Chapter 1. Configuring TCP/IP This chapter explains how to configure an iSeries 400 ® server for T ransmission Control Pr otocol/Internet Protocol (TCP/IP). If this is the first time that you have configured TCP/IP on an iSeries, you should r ead the entire chapter before performing any of the configuration tasks.
v W orking with TCP/IP host tables, including configuring a TCP/IP host name and domain name v V erifying a TCP/IP connection (PING) Planning for TCP/IP Installation and Configuration If you are in char ge of configuring an iSeries server for TCP/IP communications you will, in most cases, include your server in an existing TCP/IP network.
“ Step 6 — Configuring TCP/IP Host T able Entries ” on page 18. For information about configuring and using a DNS server , see DNS(http://publib.boulder .ibm.com/pubs/html/as400/v5r1/ic2924/info/rzakk/ rzakkkickoff.htm) in the Information Center .
T able 1. Line Description Parameters (continued) Line T ype *ELAN *TRLAN *WLS *DDI *FR *X25 *ASYNC *PPP *TDLC Network controller R Connection type R Logical channel identifier R Logical channel type .
T able 2. Local TCP/IP Host Information (continued) X.25 / Remote System Information Host #1 Host #2 Host #3 Internet address X.25 network address PVC channel ID Packet or window size Once you have documented configuration information, you are r eady to install the TCP/IP pr ogram on your server .
v Automatic IPL The Automatic IPL option determines whether the system automatically starts when the installation process has completed successfully . When TCP/IP successfully installs, either the Work with Licensed Programs menu or the Sign On display appears.
v Option 5. Start TCP/IP servers: Select this option to issue the Start TCP/IP Server (STR TCPSVR) command. This command is used to start the TCP/IP application servers that are shipped with OS/400 ® or the TCP/IP licensed program (5769-TC1). This command starts the TCP/IP application server jobs in the QSYSWRK subsystem.
Following are descriptions of the Configur e TCP/IP menu options. v Option 1. W ork with TCP/IP interfaces: Select this option to add TCP/IP interface information to the list of current interfaces or to display , change, print, or remove TCP/IP interface information that you have alr eady added.
server) was removed fr om the menu. Option 12, formerly Change local domain and host names, was renamed to Change TCP/IP domain information. v Option 20. Configure TCP/IP applications: Select this option to configure the TCP/IP applications that ar e installed on your system.
3. Configuring TCP/IP routes 4. Configuring TCP/IP attributes 5. Configuring remote system information (X.25) 6. Configuring host table entries 7. Configuring local domain and host name 8.
Subnet mask Defines which part of an Internet address forms the subnet (subnetwork) field of an Internet address. An example of a single-network subnet mask is: 255.
When you are finished adding entries, the W ork with TCP/IP Interfaces display looks like Figure 4. Note: Any change to the TCP/IP interfaces configuration, except for the automatic start parameter , takes effect immediately .
same network that the server is attached to. Y ou must also add routing entries to allow TCP/IP clients that ar e attempting to reach your server fr om a remote network to function correctly . For example, suppose that someone using a PC is using the TELNET application to start a remote terminal session on your server .
Preferred binding interface The preferr ed binding interface allows administrators to choose which of the TCP/IP interfaces that they pr efer the route to be bound to or on. This provides the administrator with mor e flexibility to route traf fic over a specific interface.
Note: Any changes that you make to the routing information take ef fect immediately . Multiple Default Routes Default routes ar e used to route data that is being addr essed to a remote destination and that does not have a specific route defined. Default r outes are based on the availability of the next hop r outer and the type of service (TOS).
Step 4 — Configuring TCP/IP attributes T o configure the TCP/IP attributes, type option 3 on the Configure TCP/IP menu. The Change TCP/IP Attributes (CHGTCP A) display is shown (Figure 8). For information about the various parameters for this command, see the online help.
T ype option 1 (Add) at the input-capable top list entry to go to the Add TCP/IP Remote System (ADDTCPRSI) display , as shown in Figure 10. The network controller used by iSeries TCP/IP does not allow you to specify X.
information. If DDN is specified as *YES on the X.25 connection, you should not specify remote system information for that interface or its associated DDN network systems.
T o add an entry to your local host table, type option 10 on the Configure TCP/IP menu. The W ork with TCP/IP Host T able Entries display is shown in Figure 1 1. Note: Just as iSeries TCP/IP automatically cr eates a LOOPBACK interface, it also automatically adds an entry to your local host table to associate the IP address 127.
The iSeries TCP/IP host table is shipped with the LOOPBACK entry . The LOOPBACK entry has an Internet address of 127.0.0.1 and two host names: LOOPBACK and LOCALHOST . The 127.0.0.1 Internet address can be changed (CHGTCPHTE) and a dif ferent one can be added (ADDTCPHTE).
Additional host names are useful as alternative nicknames. See the examples in Figure 15. Host names need not be unique. When searching the host table with a duplicate host name, the result is random. However , IP addr esses have to be unique. The uniqueness of the IP addr ess is enforced at the time you try to add a new entry to the host table.
v Simple Mail T ransfer Protocol (SMTP) r equires your host name to be in the host table or on a domain name server . v Y ou may want to use your host table on other systems in the network. Y our host name must be in the host table on those systems so they can refer to your system by name.
(http://publib.boulder .ibm.com/pubs/html/as400/v5r1/ic2924/info/rzaku/ rzakuconcat.htm) in the Information Center . If you are using the Supplemental Manuals CD, then switch to the iSeries Information Center CD to access this information. T o change the local domain name, type option 12 on the Configure TCP/IP menu.
Step 8 — Starting TCP/IP and TCP/IP Servers Before any TCP/IP services ar e available on the iSeries system, TCP/IP processing must be initialized and activated. T o start TCP/IP , you have two options: 1. Select option 3 from the TCP/IP Administration menu (GO TCP ADM), 2.
Using the Start TCP/IP Server (STR TCPSVR) command starts the servers individually or together . Y ou can monitor the jobs with option 20 (W ork with TCP/IP jobs in QSYSWRK subsystem) fr om the TCP/IP Administration menu.
T able 3. Jobs Used by TCP/IP (continued) Job Name Description ADMIN and DEF AUL T I CS (HTTP) server QTWSGxxxxx W orkstation gateway (there may be several) Note: 1. There may be other jobs running in the QSYSWRK subsystem that have nothing to do with TCP/IP .
3. If the PING operation is successful, you should see messages similar to those in Figure 18. If the PING operation is unsuccessful, you should see messages similar to those in Figure 19. If you receive an unsuccessful PING message, check your configuration steps.
additional systems to your network, you also need to verify their TCP/IP connection. The examples in the following paragraphs show you how to verify a remote TCP/IP connection. Use the system menus or the V erify TCP/IP Connection (VFYTCPCNN or PING) command to verify your system ’ s ability to communicate with a remote system using TCP/IP .
V erifying TCP/IP Connections with Host Name — Example In this example, sending five packets of 256 bytes each verifies the connection to the remote system SYSNAM36 . The local system waits 1 second for a r esponse to each packet that is sent. Verify TCP/IP Connection (PING) Type choices, press Enter.
V erifying TCP/IP Connections with Internet Address — Example In this example, (Figure 22) the connection to the remote system at Internet addr ess 9.4.191.76 is verified using the system defaults for packet length, number of packets, and wait time.
Note: Y ou do not have to end TCP/IP in or der to save the configuration files. However , you should end TCP/IP before any TCP/IP configuration files are restor ed.
32 OS/400 TCP/IP Configuration and Refer ence V5R1.
Chapter 2. TCP/IP: Operation, Management, and Advanced T opics This chapter discusses managing your network by using the NETST A T command, and the maintenance of host tables. In addition, this chapter covers other topics beyond those that are r equired to configur e and use TCP/IP on iSeries 400.
Work with TCP/IP Interface Status The W ork with TCP/IP Interface Status display , as shown in Figure 25, provides the most current summary of interface activity . This display allows you to view TCP/IP interface information for selected interfaces and to start or end TCP/IP interfaces.
Starting TCP/IP Interfaces TCP/IP interfaces ar e started in one of the following ways: v The W ork with TCP/IP Interface Status displays ar e reached by: – Option 1 on the Configure TCP/IP (CFGTCP).
depends mainly on machine use and the size of the processor . T o determine whether the interface has started, view the messages in the QTCPIP job log and the QSYSOPR message queue. Ending TCP/IP Interfaces The ENDTCPIFC (End TCP/IP Interface) command ends an existing TCP/IP interface immediately .
v The network ID of the interface must be equal to the logical AND of the next hop for the route and the subnet mask for the interface. Notes: 1. If the next hop of a route is identical to an interface ’ s IP addr ess, that route will never be bound to another interface.
T o view detailed information about a specific route, type 5 in the option field next to the route and pr ess the Enter key . Routes listed on the Display TCP/IP Route Information display dif fer from the routes that ar e displayed on the W ork with TCP/IP Routes display .
contain an asterisk (*). When an application requests a connection to a listening socket, a new connection is created. The r emote Internet address and r emote port are shown for the new connection. The listening socket always r emains in the list of connections.
Ending TCP/IP Connections TCP/IP connections and User Datagram Pr otocol (UDP) sockets can be ended from the W ork with TCP/IP Connection Status display . T o do so: 1. T ype 4 in the option field for the lines containing the connections that you want to end.
T o end the TCP/IP connections, pr ess the Enter key from the Confirm End of TCP/IP Connections display . If you decide not to end a TCP/IP connection or if you want to change your choices, press F12 (Cancel). Working with Configuration Status T o work with the line description used by an interface: 1.
Displaying TCP/IP Network Status Information In addition to working with network status functions, the W ork with TCP/IP Network Status menu allows you to display current information about your TCP/IP network, including multicast gr oups, TCP/IP interfaces, and associated routes, to name a few .
Displaying TCP/IP Interfaces T o display more detailed information about the TCP/IP interface status for specific interfaces: 1. On the W ork with TCP/IP Interface Status display , type 5 in the option field for each interface about which you want more information.
Displaying Associated Routes T o display information about the routes associated with a specific interface: 1. On the W ork with TCP/IP Interface Status display , type 8 in the option field for each interface for which you want to see the associated routes information.
Press F1 1 to show the display that includes the type of service (TOS), maximum transmission unit (MTU), type, and source. Displaying Route Details Option T o display detailed information about the route: 1. On the Display Associated Routes display , type 5 in the option field for each route about which you want mor e information.
Displaying TCP/IP Route Information T o display TCP/IP r oute information: 1. On the W ork with TCP/IP Network Status menu, type 2 on the command line or enter the WRKTCPSTS *RTE command. 2. Press the Enter key . The first of the two Display TCP/IP Route Information displays is pr esented as shown in Figure 39 on page 47.
T o view the second Display TCP/IP Route Information display , press F1 1 (Display route type). The r oute information is presented in Figur e 40. T o return to the first display , press F1 1 (Display next hop). T o view detailed information about a specific route, type 5 in the option field next to the route and pr ess the Enter key .
Displaying TCP/IP Connections Y ou can request mor e detailed information about TCP/IP connections shown on the W ork with TCP/IP Connection Status display . This information includes timing information and transmission statistics for the connection displayed.
Displaying Connection T otals T o display a summary of TCP and UDP counts, press F10 on the W ork with TCP/IP Connection Status display . The counts provided ar e a cumulative summary of all TCP and UDP activity since the last time the STR TCP (Start TCP) command was issued.
(SNMP). For additional information about SNMP , see resour ces in the Information Center: Supplemental Manuals. TCP/IP Host T ables Host tables are a method for mapping host names to IP addr esses. This is done by using a hosts file for name-to-address r esolution.
Managing TCP/IP Host T ables In a large network, it can be mor e efficient to administer iSeries TCP/IP from a central site. W orking with the host table would be time consuming if each system is individually updated with the TCP/IP configuration menu.
A complete description of the *NIC format is found in Request for Comment (RFC) 952, Internet Host T able Specification . See the RFC Editor Site (http://www .rfc- editor .org/rfc.html) to retrieve this RFC. The subset supported on the server is shown in T able 5.
v Merge the information of the imported host table with the information that was entered by using option 10 (W ork with TCP/IP host table entries) from the Configure TCP/IP menu. T o merge the information, specify Replace Host Table (*No) on the Merge Host T able display .
Step 4 — Merge the File T ype the following FTP subcommand: quote rcmd mrgtcpht fromfile(qusrsys/m03host) frommbr(host) IP Routing and Internet Control Message Protocol (ICMP) Redirecting Internet routing tables usually r emain static for long periods.
T o see routing changes due to ICMP redir ect messages, select NETST A T menu 2 or NETST A T *RTE and then pr ess PF1 1. Comparing the next hop in this display with the next hop present in the r outing table, you can verify whether a route has been dynamically changed.
The data link layer passes a negative advice indicator to IP when it is unable to transmit data to a first-hop (directly-connected) gateway . In most cases, negative advice from the data link layer me.
Note: The maximum number of interfaces that can be active on a line description at any given time is 128. This is true for all line types (for example, token-ring, Ethernet, frame relay , and so forth). Example: A Single Host on a Network over a Communications Line Y our server uses one adapter for TCP/IP to attach to a LAN or W AN network.
addresses, your server appears as multiple TCP/IP hosts in the same TCP/IP network (Figure 49). This scenario can be helpful for backup or to improve performance.
an Internet address of dif ferent TCP/IP networks. W ith these multiple Internet addresses, you take part in dif ferent TCP/IP networks (Figure 51). This example is a combination of all of the previous examples discussed. Example: The Multihoming function Assume servers SYSNAM02 and SYSNAM03 are connected with a public or private X.
T ype of Service (T OS) T ype of Service (TOS) is a parameter defined to indicate a quality of the service desired by an application pr ogram. It is specified within a single octet of the IP datagram header , and it is used to select Internet service.
The following table shows which type of services your server uses for some of the TCP/IP applications: T able 6. AS/400 TCP/IP applications and T ype of Services Protocol or Application T ype of Servi.
a specific route defined. The system allows up to eight default r outes, but each route must have a unique next hop value. An example of a multiple route table can be found in Figur e 54. TCP/IP Port Restriction TCP and UDP pr otocols use ports to identify a unique origin or destination of communication with an application.
the specified port. If no match is found, the requesting pr ogram is not allowed to use the specified port. If any port in the 1-1023 range is restricted, the following message is posted: Port restriction added but may affect TCP/IP processing If no user profiles ar e associated with a specific port, there ar e no restrictions.
Let us assume we have an application that uses Port 1060 in the TCP layer and we want to restrict its use to user pr ofile GERR Y . T ype the information as shown in Figure 56. Figure 57 shows what the display looks like after you enter port information for both user profiles P AOLO and GERRY .
Related T ables and the Host T able Socket applications requir e a set of tables from which they can r etrieve specific TCP/IP network data when needed. These ar e as follows: v Host table v Service table v Protocol table v Network table The host table contains a list of host names and corresponding Internet addr esses.
The services table stores the mapping of services to ports or ports to services as shown in Figure 59. The mapping information is usually accessed with the getservbyname() and getservbyport() socket functions. The protocol table stor es the mapping of protocol names to pr otocol numbers and protocol numbers to pr otocol names.
The network table contains the networks and the Internet address associated with the network. Socket applications use the getnetbyname() and getnetbyaddr() functions to access the information in the network table (Figure 61). The protocols and services tables that ar e shipped contain standard information.
The TCP/IP interface now points to a specific PVC instead of a pool of SVCs. ADDTCPIFC INTNETADR('9.4.73.65') LIND(X25LINE) SUBNETMASK('255.255.255.192') PVCLGLCHLI(001) MAXSVC(0) The TCP/IP r emote system information no longer includes the X.
supported on multi-access nonbroadcast networks. IP multicast is also not currently supported on Frame Relay , FDDI/SDDI, or A TM networks. T o determine whether an interface supports multicast, enter option 14 on the W ork with TCP/IP Interface Status display .
70 OS/400 TCP/IP Configuration and Refer ence V5R1.
Chapter 3. TCP/IP Performance The following are performance items that should be consider ed when using TCP/IP . *BASE Pool Size The TCP/IP pr otocol and application code always runs in the *BASE pool on the iSeries 400 server .
v Checksum calculation of outgoing TCP and UPD datagrams (prior to V4R4) v Checksum verification of incoming TCP and UPD datagrams (prior to V4R4) v Outbound batching of TCP and UDP datagrams. v Fragmentation of TCP and UDP datagrams into segments that match the MTU size.
Note: If you configure your 100 Mbps ethernet line for TCPONL Y , all IOP assist functions are disabled. TCP/IP-assist functions that are available on frame r elay IOAs are: v #2699 T wo-Line W AN IOA.
If you have one of these configurations, you can use the TCPONL Y parameter when you create or change your Ethernet line descriptions. Setting TCPONL Y to *YES in other hardwar e configurations has no effect on the line.
Appendix A. Configuring a Physical Line for TCP/IP Communication On the iSeries 400, communication occurs through objects called lines, contr ollers, and devices. The communications objects for iSeries TCP/IP ar e the line descriptions, the network controller descriptions, and the network device descriptions.
Y ou can describe the characteristics of the communications devices using the by Create Device Description (Network) (CR TDEVNET) command or by letting the system create the device automatically when you activate TCP/IP .
If the Ethernet standard pr ompt is *ETHV2 , the system sends and receives all TCP/IP data in Ethernet V ersion 2 frames. Y ou do not need to configure any additional SSAPs for TCP/IP .
78 OS/400 TCP/IP Configuration and Refer ence V5R1.
Appendix B. TCP/IP Application Exit Points and Programs Certain TCP/IP applications pr ovide exit points that enable them to call customer-written exit pr ograms.
OS/400 Registration Facility Exit points for TCP/IP applications ar e automatically register ed when the parent product or option is installed, using the OS/400 registration facility . The registration facility contains a r epository that allows customers to associate their exit programs with specific exit points.
T able 9. TCP/IP Application Exit Points (continued) TCP/IP Application Exit Point Exit Point Format Note: 1 The same interface format is used for request validation for the FTP client, FTP server , REXEC server , and TFTP server . This allows the use of one exit program for request validation of any combination of these applications.
Step 1. Select your exit point T ype 8 next to the exit point to which you want to add an exit program. For example, to associate a program with the WSG server sign-on validation exit point, type an 8 next to this exit point, as shown. The W ork with Exit Programs display is shown.
Step 2: Select the Add Exit Program option Select the add option by typing a 1 (Add) in the Opt column as shown in Figure 66. Step 3: Add your exit program Fill in the exit program information as shown in Figur e 67 on page 84 and Figure 68 on page 84, then press enter .
When you add workstation gateway server exit programs, you do not need to end and restart the workstation gateway server . The WSG server checks for the exit program dynamically . When you add REXEC server exit programs, you do not need to end and restart the REXEC server .
Exit Point Interfaces for TCP/IP Application Exit Points The exit point interfaces for TCP/IP application exit points ar e: v TCP/IP application r equest validation exit point interface v TCP/IP r emo.
3 TFTP server program Operation identifier INPUT ; BINARY(4) Indicates the operation that the user is attempting to perform. When the application identifier indicates the FTP client or FTP server prog.
For operation identifiers 1 through 3, the operation-specific information contains the name of the directory or library on which the operation is to be performed.
T able 10. Application Request V alidation Operation-Specific Information Operation Identifier Operation-Specific Information 0 NONE if application ID=0 0 Dotted decimal format IP addr ess of client host when application ID=1 or 2 1-3 Absolute path name of library or directory /QSYS.
3. If any exception is encountered when calling the exit pr ogram, the REXEC server will not allow the operation and the message ″ Exception encountered for REXEC exit program &1 in library &2 for exit point &3. ″ is issued to the job log.
Command processor identifier OUTPUT ; BINARY(4) Indicates the command pr ocessor that you want the server to use for interpreting and r unning the command. The following values are valid: 0 iSeries Control Language The server processes the command as an iSeries contr ol language (CL) command.
If the Qshell Interpreter option of OS/400 is not installed, the REXEC client receives (in the stdout str eam) a REXEC protocol diagnostic message that says “ Qshell interpreter not installed ” .
92 OS/400 TCP/IP Configuration and Refer ence V5R1.
Notices This information was developed for products and services of fered in the U.S.A. IBM may not offer the pr oducts, services, or features discussed in this document in other countries. Consult your local IBM repr esentative for information on the products and services curr ently available in your area.
programs and other pr ograms (including this one) and (ii) the mutual use of the information which has been exchanged, should contact: IBM Corporation Software Inter operability Coordinator 3605 Highway 52 N Rochester , MN 55901-7829 U.
AS/400e AT C/400 CICS/400 Client Access CT DB2 Distributed Relational Database Architectur e DRDA e (Stylized) IBM IBM Global Network Integrated Language Environment Intelligent Printer Data Stream IP.
96 OS/400 TCP/IP Configuration and Refer ence V5R1.
Index Special Characters *AIX format 51 *AS400 format 51 *BASE pool size 71 *IOSYSCFG authority 10 *NIC format 51 *SYSGEN default value 10, 76 (T ransmission Control Pr otocol/Internet Protocol) attri.
dead gateway processing 55 default route adding 15 display TCP/IP connections 48 displaying system name and address 19 distributed data interface (DDI) fiber distributed data interface (FDDI) 2 shield.
N NETST A T (Network Status) command 33 network interface types supported 75 Network Status (NETST A T) command 33 network status for TCP/IP connections display 40, 48 display totals 49 end 40 general.
TCP/IP (T ransmission Control Protocol/Internet Pr otocol) (continued) QTSMTPSR VR 25 planning for installation and configuration 2 QSYSWRK subsystem 25 starting 24 TCP/IP Administration (TCP ADM) men.
.
Printed in the United States of America on recycled paper containing 10% recovered post-consumer fiber . SC41-5420-04.
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il IBM SC41-5420-04 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del IBM SC41-5420-04 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso IBM SC41-5420-04 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul IBM SC41-5420-04 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il IBM SC41-5420-04, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del IBM SC41-5420-04.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il IBM SC41-5420-04. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo IBM SC41-5420-04 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
