Planning considerations for your backup console

 

Most system plans include a level of redundancy to allow for the event of hardware failures; however, many people do not consider the console in their plans. To recover quickly from an unexpected loss of your console, plan for a backup console.

 

Considerations for a backup console

• The adapter location is fixed, or at least limited, for independent systems or primary partitions. Based on your system's hardware requirements, you might have limited choices of console types. Try to accommodate at least one additional console type, if possible.

• Consider using the take over and recovery option as part of your backup console strategy. However, the hardware used for the new console type must exist and be available at the time of recovery.

• If you are working in a partitioned environment, consider:

  • In a logical partition environment, the term alternate console refers to the twinaxial console type located in another input/output processor (IOP) that is tagged as the alternate console. If a failure of the primary console (twinaxial only) is detected, the system automatically tries the alternate console's IOP. This function gives you another level of protection. Tagging a single IOP as both the primary console and the alternate console can result in errors when selecting a console. Further isolation can be planned by placing the alternate console IOP on a different bus so that failures of the primary console's bus cannot prevent a console from being available.

  • Models 270 and 8xx are tagged for a console type only at the IOP level. Tagging an IOP that has two alike console adapters reporting to it, for example two 2849s or two 2771s, for the same IOP can sometimes make it difficult to determine, in advance, which adapter will be used for the console. When tagging the IOP, be sure that it only has one console-capable adapter per connectivity. For example, only one 2849 and one 2771. Each adapter can support a different console type but only one adapter type should be present. The lowest addressed adapter on the bus is attempted first. But if that adapter is slow in reporting to the system, another adapter might get selected instead, when two adapters of the same connectivity are present. Another example of this might be that the IOP has both a 2838 and a 2849 Ethernet adapter reporting to it. They are different adapters but have the same connectivity for the console.

  • Consider a shared resource environment in which you can allocate and deallocate a console supporting IOP to a partition on a part-time basis. Many work environments rarely need a console device on a full-time basis and you can reduce your initial cost of dedicated hardware by implementing this concept.

  • If the load source storage device fails and the system recovery includes the use of the IBM^® distribution Licensed Internal Code media instead of a customer backup, and the system is using Operations Console (LAN), you might have to use another console type for the initial portion of the system recovery.

 

Configuration types for backup consoles

When planning the configuration of the backup console or consoles remember that recovering from the loss of the console depends on many factors. Some of these factors include, the model and series, the hardware resources available, the previous console type, and the intended console type. Recovery might consist of repairing the currently failed console or temporarily replacing it with another console type. Most changes of a console type can be performed without the need for an IPL but there may be circumstances in which an IPL will still be necessary. When using the console service functions (65+21), console-supporting hardware must be installed and available prior to performing the function. Any partition tagging of resources must also have been done already.

If you plan to use Operations Console local console on a LAN as a backup to another console type, the network adapter must be located in a console designated slot or in a properly tagged IOP. If not previously configured, the BOOTP process is used to configure the system.

 

Backup console configuration considerations

• If you access your system remotely, consider off-site console capability or another type of connectivity for the console. A local console on a network can be backed up with an additional local console on a network PC. If the network adapter were to fail, consider a local console directly attached to the server as a backup. By changing the console type to a local console directly attached to the server with remote access, you can add the ability for a remote PC to become the console.

• In a logical partition or multiple-system environment, you will most likely be using multiple local consoles on a network (LAN) configuration on a single PC as your primary consoles. Consider additional PCs using this same type configuration. Avoid supporting too many consoles on the same PC if possible. The PC resources can be easily overwhelmed when supporting multiple consoles and remote control panels.

• Consider multiple local console on a network configurations in large environments so that each PC has a core set of console responsibilities and the overlap coverage of backup configurations with each other. For example, if you have a PC that supports 10 local consoles on a network configuration and another PC with the same number of primary consoles for another 10 partitions, instead of backing up each PC with the other's configuration, you add a third PC and spread the 20 consoles out so that two PCs back up a portion of each PC's primary console configurations. Another consideration is a dedicated PC to be the backup of a certain number of consoles, but not connected until necessary.

• When you mostly use consoles on a network, consider setting up a local console directly attached to the server on a PC and place it on a rollaway cart with a console cable. If you have supporting adapters, you can quickly roll the cart with the PC near the system or partition in need of the console. After connecting the cable and changing the console type value, you have a console to replace the currently failed console. This same concept can be implemented for twinaxial workstations just as easily.

If more than one local console on a network is planned, be certain to create additional service tools device IDs on the system before you start configuring the Operations Console PC. Each PC connecting to the same target system or logical partition must have a unique service tools device ID.

In summary, consider incorporating as much redundancy as possible into your console configuration. You can reduce your exposure to a catastrophic console failure by using another method to provide a console in place, or by making compromises and adjustments for the various hardware requirements necessary to overcome the various levels of failures.

For more information on switching between console devices, see the Managing your multiple consoles topic.

 

Parent topic:

Planning considerations for your configuration

 

Related reference

Console planning considerations
Takeover or recovery of an Operations Console connection
Preparation for your network environment
Management of multiple consoles
Scenario: Consoles for multiple systems or partitions
Takeover or recovery of an Operations Console connection
Preparation for your network environment