Compaq AA-RHGWC-TE manual 2 MC2 Jumpers

Table 5–1: MC1 and MC1.5 Jumper Configuration (cont.)

If hub mode is:	Jumper:	Example:
Virtual: VH0	Pins 2 to 3

1 2 3

Virtual: VH1 None needed; store the jumper on pin 1 or 3

1 2 3

If you are upgrading from virtual hub mode to standard hub mode (or from standard hub mode to virtual hub mode), be sure to change the jumpers on all Memory Channel adapters on the rail.

5.1.2 MC2 Jumpers

The MC2 module (CCMAB) has multiple jumpers. They are numbered right to left, starting with J1 in the upper righthand corner (as you view the jumper side of the module with the endplate in your left hand). The leftmost jumpers are J11 and J10. J11 is above J10.

Most of the jumper settings are straightforward, but the window size jumper, J3, needs some explanation.

If a CCMAA adapter (MC1 or MC1.5) is installed, 128 MB of address space is allocated for Memory Channel use. If a CCMAB adapter (MC2) PCI adapter is installed, the memory space allocation for Memory Channel depends on the J3 jumper and can be 128 or 512 MB.

If two Memory Channel adapters are used as a failover pair to provide redundancy, the address space allocated for the logical rail depends on the smaller window size of the physical adapters.

During a rolling upgrade (see Section 5.7) from an MC1 failover pair to an MC2 failover pair, the MC2 modules can be jumpered for 128 MB or 512 MB. If jumpered for 512 MB, the increased address space is not achieved until all MC PCI adapters have been upgraded and the use of 512 MB is enabled. On one member system, use the sysconfig command to reconfigure the Memory Channel kernel subsystem to initiate the use of 512 MB address space. The configuration change is propagated to the other cluster member systems by entering the following command:

# /sbin/sysconfig -r rm rm_use_512=1

Setting Up the Memory Channel Cluster Interconnect 5–3