Designing Disaster Recovery Clusters using Metroclusters and Continentalclusters, Reprinted October 2011 (5900-1881)

Figure 3 Failover Scenario with Two Arbitrators
The scenarios in Table 5 illustrate possible results if a data center or one or more nodes fail in a
configuration with two arbitrators. Note that 3 of the 4 scenarios that caused a cluster halt with a
single arbitrator, do not cause a cluster halt with two arbitrators.
Table 5 Node Failure Scenarios with Two Arbitrators
ResultQuorumFailure
pkg A and B switch to data center B4 of 6 (67%)data center A (nodes 1 and 2)
pkg A and B switch, then no change3 of 4 (75%)data center A, then arbitrator 1
cluster halts*3 of 6 (50%)data center A and arbitrator 1
pkg A, B, and C switch2 of 3 (67%)data center A, then arbitrator 1, then node 3
pkg A and B switch to data center B3 of 5 (60%)arbitrator 1, then data center A
pkg A and B switch to data center B3 of 5 (60%)node 3, then data center A
pkg C and D switch to data center A4 of 6 (67%)data center B
no change4 of 6 (67%)third location
* Cluster can be manually started with the remaining node.
Worksheets
Disaster Tolerant Checklist
Use this checklist to make sure you have adhered to the disaster tolerant architecture guidelines
for a two main data centers and a third location configuration.
Worksheets 31