Serial over LAN (SOL) provides a means to manage servers remotely by using a command-line interface (CLI) over a Telnet or Secure Shell (SSH) connection. SOL is required to manage servers that do not have keyboard/video/mouse (KVM) support, such as the JS20 Type 8842 blade server.
SOL provides console redirection for both BIOS and the blade server operating system. The SOL feature redirects server serial-connection data over a LAN without the need for special cabling. The SOL connection enables blade servers to be managed from any remote location with network access. The advantages of SOL include:
The IBM® BladeCenter® management module command-line interfaces provide access to the text-console command prompt on each blade server through a SOL connection, enabling the blade servers to be managed from a remote location. This document explains how to update and configure BladeCenter components for SOL operation using the BladeCenter management-module Web interface. You can also perform many configuration procedures using the management-module command-line interface or the simple network management protocol (SNMP). See the BladeCenter Management Module Command-Line Interface Reference Guide for information about the management-module command-line interface and instructions about how to use it. All BladeCenter unit types, including the BladeCenter T unit, are referred to throughout this document as the BladeCenter unit. Unless stated otherwise, all descriptions and instructions in this document apply to all BladeCenter unit configurations.
In the BladeCenter environment, the integrated system management processor (ISMP) and network interface controller (NIC) on each blade server routes the serial data from the blade server serial communications port to the network infrastructure of the BladeCenter unit, including an Ethernet-compatible I/O module that supports SOL communication. BladeCenter components are configured for SOL operation through the BladeCenter management module. The management module also acts as a proxy in the network infrastructure to couple a client running a Telnet session with the management module to an SOL session running on a blade server, enabling the Telnet client to interact with the serial port of the blade server over the network. Because all SOL traffic is controlled by and routed through the management module, administrators can segregate the management traffic for the BladeCenter unit from the data traffic of the blade servers.
To start an SOL connection with a blade server, you must first start a Telnet command-line interface session with the management module. When this Telnet command-line interface session is running, you can start a remote-console SOL session with any blade server in the BladeCenter unit that is set up and enabled for SOL operation. You can establish up to 20 separate Web interface, Telnet, serial (advanced management module only), or SSH sessions with a BladeCenter management module. For a BladeCenter unit, this enables you to have 14 simultaneous SOL sessions active (one for each of up to 14 blade servers) with 6 additional command-line interface sessions available for BladeCenter unit management. For a BladeCenter T unit, this enables you to have 8 simultaneous SOL sessions active (one for each of up to 8 blade servers) with 12 additional command-line interface sessions available for BladeCenter unit management. If security is a concern, you can use Secure Shell (SSH) sessions, or connections made through the serial management port that is available on the advanced management module, to establish secure Telnet command-line interface sessions with the BladeCenter management module before starting an SOL console redirect session with a blade server.
The most recent versions of all BladeCenter documentation is available at http://www.ibm.com/support/.