HP serviceguard t2808-90006 manual P1 uses a mirror md0 Run the following command to

Disaster Scenarios and Their Handling
Table 4-1	Disaster Scenarios and Their Handling (Continued)
Disaster Scenario		What Happens When	Recovery Process
		This Disaster Occurs
This is a multiple failure		The package (P1) continues	In this scenario, no attempts are
scenario where the failures		to run on Node 1 after the	made to repair the first failure
occur in a particular sequence in		first failure, with the MD0	until the second failure occurs.
the configuration that		that consists of only S1.	Typically the second failure occurs
corresponds to figure 2 where		After the second failure, the	before the first failure is repaired.
Ethernet and FC links do not go
		package P1 fails over to N2	1. To recover from the first
over DWDM.
		and starts with S2. Data	failure, restore the FC links
The RPO_TARGET for the package		that was written to S1 after
			between the data centers. As a
P1 is set to IGNORE.		the FC link failure is now
			result, S1 is accessible from
		lost because the
The package is running on Node			N2.
		RPO_TARGET was set to
1. P1 uses a mirror md0			2. Run the following command to
		IGNORE.
consisting of S1 (local to node
			add S1 to md0 on N2:
N1, - /dev/hpdev/mylink-sde)
and S2 (local to node N2). The			# mdadm --add /dev/md0
first failure occurs when all FC			/dev/hpdev/mylink-sde
links between the two data			This command initiates the
centers fail, causing Node 1 to
			re-mirroring process. When it
lose access to S2 and Node 2 to
			is complete, the extended
lose access to S1.
			distance cluster detects S1
After sometime a second failure			and accepts it as md0.
occurs. Node 1 fails (because of			For the second failure, restore N1.
power failure)
			Once it is restored, it joins the
			cluster and can access S1 and S2.
			1. Run the following command to
			enable P1 to run on N1
			# cmmodpkg -e P1 -n N1

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