Transfer of a Modem Session

Because many modem command variations exist, the sample modem configuration files located at the end of this appendix have been written to capture the largest number of workable modem settings.

The modem command &Dn (where n is a number) generally sets the modem response to the Data Terminal Ready (DTR) signal from the server's serial port. The desired response is that the modem will hold a connection while DTR is enabled, and drop the connection when DTR is released. Using this mechanism, the server hangs up on a connection under normal conditions.

Consult your modem manual for its specific response scheme for the &Dn command.

Two strategies are available for dealing with the modem's response to DTR:

vRecovery

vPrevention

Before you use one of these strategies, determine if your server's modem is set up correctly to respond to DTR.

With the remote terminal connected to serial port 1 and defined as the Primary Console Device, there are two tests you can perform:

1.Will the modem drop the connection after the System initialization complete message displays at the remote terminal?

If Yes, the modem is set up correctly.

If No, try another &Dn setting for your server's modem. See your modem manual for this information. The &Dn command appears in three places each in three of the sample modem configuration files, as follows:

2.Will the server's modem disconnect when the power drops? You can make this

observation at the remote terminal by commanding your server to shut down and power off. (Use the AIX command shutdown -F.) Watch for the message NO CARRIER on your remote terminal.

If Yes, this is the correct response. The modem is set up correctly.

If No, try another &Dn setting for your server's modem. See your model manual for this information. The &Dn command appears in three places each in three of the sample modem configuration files. Only the following sample modem configuration files contain the &Dn command (in three places each):

vmodem_f.cfg

vmodem_f0.cfg

vmodem_f1.cfg

If you are using modem_z.cfg or modem_z0.cfg, you cannot control DTR response. If your remote terminal does not disconnect after logging off, you must command the remote terminal emulator to hang up. This then breaks the connection.

Appendix D. Modem Configurations 169

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IBM pSeries690 manual Transfer of a Modem Session

pSeries690 specifications

The IBM pSeries690, also known as the IBM eServer p690, is a high-performance server within IBM's line of Power Systems, designed primarily for enterprise-level workloads. Launched in the early 2000s, it distinguished itself as one of IBM's flagship offerings, aimed at delivering exceptional scalability, reliability, and processing power.

At the heart of the pSeries690 is the IBM POWER4 processor, a revolutionary architecture that significantly enhanced processing capabilities. The system supports multiple processor configurations, allowing businesses to customize performance based on their specific applications. Each pSeries690 can be configured with up to 32 POWER4 processors, providing a maximum processing power that is well-suited for demanding enterprise applications, complex databases, and large-scale transaction processing.

One of the standout features of the pSeries690 is its ability to handle massive amounts of memory — up to 1TB of total RAM. This is particularly advantageous for businesses that run memory-intensive applications or require high availability for critical tasks. The server’s advanced memory architecture contributes to faster data access and improved overall system performance.

Additionally, the IBM pSeries690 employs the innovative AIX operating system, which is tailored for high performance and reliability. AIX comes equipped with features such as dynamic logical partitioning (LPAR), allowing resources to be allocated flexibly and efficiently across different workloads. This technology supports virtualization, enabling multiple operating environments to run concurrently on a single physical server, optimizing resource utilization.

The pSeries690 also includes robust fault tolerance and reliability features. Redundant components, hot-swappable parts, and advanced error detection mechanisms ensure that the system remains operational even in the event of hardware failures. This reliability is crucial for mission-critical applications where downtime can lead to substantial financial losses.

Networking capabilities of the pSeries690 are enhanced by support for high-speed connections, including Gigabit Ethernet and the ability to integrate with various network topologies. This versatility facilitates seamless connectivity in complex IT environments.

In conclusion, the IBM pSeries690 remains a powerful and reliable choice for enterprises seeking to manage and optimize their most demanding workloads. Its combination of cutting-edge processing capabilities, expansive memory support, and robust virtualization features makes it a significant player in the realm of enterprise computing. As businesses continue to evolve, the core strengths of the pSeries690, especially in terms of scalability and reliability, ensure that it continues to meet the needs of demanding applications.