Terminal Concentrator and System Service Processor FAQs

Does the Sun Cluster system require a terminal concentrator?

No software releases starting with Sun Cluster 3.0 require a terminal concentrator to run. Unlike the Sun Cluster 2.2 product, which required a terminal concentrator for failure fencing, later products do not depend on the terminal concentrator.

I see that most Sun Cluster servers use a terminal concentrator, but the Sun Enterprise E1000 server does not. Why not?

The terminal concentrator is effectively a serial-to-Ethernet converter for most servers. The terminal concentrator's console port is a serial port. The Sun Enterprise E1000 server doesn't have a serial console. The System Service Processor (SSP) is the console, either through an Ethernet or jtag port. For the Sun Enterprise E1000 server, you always use the SSP for consoles.

What are the benefits of using a terminal concentrator?

Using a terminal concentrator provides console-level access to each node from a remote workstation anywhere on the network. This access is provided even when the node is at the OpenBoot PROM (OBP) on a SPARC based node or a boot subsystem on an x86 based node.

If I use a terminal concentrator that Sun does not support, what do I need to know to qualify the one that I want to use?

The main difference between the terminal concentrator that Sun supports and other console devices is that the Sun terminal concentrator has special firmware. This firmware prevents the terminal concentrator from sending a break to the console when it boots. If you have a console device that can send a break, or a signal that might be interpreted as a break to the console, the break shuts down the node.

Can I free a locked port on the terminal concentrator that Sun supports without rebooting it?

Yes. Note the port number that needs to be reset and type the following commands:

telnet tc
Enter Annex port name or number: cli
annex: su -
annex# admin
admin : reset port_number
admin : quit
annex# hangup
#

Refer to the following manuals for more information about how to configure and administer the terminal concentrator that Sun supports.

• Administering Sun Cluster Overview in Sun Cluster System Administration Guide for Solaris OS

• Chapter 2, Installing and Configuring the Terminal Concentrator, in Sun Cluster 3.0-3.1 Hardware Administration Manual for Solaris OS

What if the terminal concentrator itself fails? Must I have another one standing by?

No. You do not lose any cluster availability if the terminal concentrator fails. You do lose the ability to connect to the node consoles until the concentrator is back in service.

If I do use a terminal concentrator, what about security?

Generally, the terminal concentrator is attached to a small network that system administrators use, not a network that is used for other client access. You can control security by limiting access to that particular network.

SPARC: How do I use dynamic reconfiguration with a tape or disk drive?

Perform the following steps:

• Determine whether the disk or tape drive is part of an active device group. If the drive is not part of an active device group, you can perform the DR remove operation on it.

• If the DR remove-board operation would affect an active disk or tape drive, the system rejects the operation and identifies the drives that would be affected by the operation. If the drive is part of an active device group, go to SPARC: DR Clustering Considerations for Disk and Tape Drives.

• Determine whether the drive is a component of the primary node or the secondary node. If the drive is a component of the secondary node, you can perform the DR remove operation on it.

• If the drive is a component of the primary node, you must switch the primary and secondary nodes before performing the DR remove operation on the device.

If the current primary node fails while you are performing the DR operation on a secondary node, cluster availability is impacted. The primary node has no place to fail over until a new secondary node is provided.