Understanding and Designing Serviceguard Disaster Recovery Architectures

(and 10, 12, 14, or 16 with CVM 5.0 or 5.0.1 and Serviceguard A.11.19, SG SMS A.02.01,
A.02.01.01 ,or SG SMS A.03.00) in this cluster if CVM or CFS is used and the distance is 10
kilometers or less. There can be only two nodes in this cluster, if CVM or CFS 4.1 is used and the
distance is between 10 and 100 kilometers. There can be 2 or 4 nodes in this cluster, if CVM or
CFS 5.0 or 5.0.1 is used and the distance is between 10 and 100 kilometers. If RAC is not used
(and CVM or CFS is used), there can be 2, 4, 6, or 8 nodes (and 10, 12, 14, or 16 nodes if SG
SMS A.02.01, A.02.01.01, or A.03.00 is used) in the cluster and up to 100 kilometers distance.
There can be only two nodes in this cluster if Shared LVM version 1.0 is used. There can be 2 or
4 nodes in this cluster if Shared LVM version 2.0 volume groups are used (LVM version 2.0 is
available in HP-UX 11i v3). See Table 3 (page 49), Table 4 (page 49) and Table 5 (page 51) for
additional restrictions due to the HP UX revision or volume manager or both being used. Note that
because there are four nodes and Oracle RAC is used in this example cluster, this cluster cannot
use SLVM as the volume manager, and the distance between the Primary data centers cannot
exceed 100 kilometers.
You can use SONET instead of WDM in this configuration by replacing the WDM boxes with
SONET boxes. With SONET, you can use a point to point topology, as is shown in this example,
or you can use a dual SONET ring topology which passes through the two Primary data centers,
where the working ring and the protection ring are alternately routed.
Extended Distance Cluster configurations with Two Data Centers and a Third Location 67