HP serviceguard t2808-90006 manual S2 is non-current by less

			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 failure is the same as the		Package P1 continues to run	In this scenario, no attempts are
previous failure except that the		on N1 after the first failure	made to repair the first failure
package (P1) is configured with		with md0 consisting of only	until the second failure occurs.
RPO_TARGET set to 60 seconds.		S1	Typically, the second failure occurs
In this case, initially the		After the second failure,	before the first failure is repaired.
package (P1) is running on N 1.		package P1 fails over to N2	1. To recover from the first
P1 uses a mirror md0 consisting		and starts with S2. This	failure, restore the FC links
of S1 (local to node N1 -		happens because the disk
			between the data centers. As a
/dev/hpdev/mylink-sde) and		S2 is non-current by less
			result, S1
S2 (local to node N2). The first		than 60 seconds. This time
			(/dev/hpdev/mylink-sde) is
failure occurs when all FC links		limit is set by the
			accessible from N2.
between the two data centers		RPO_TARGET parameter.
			2. Run the following command to
fail, causing N1 to lose access to		Disk S2 has data that is
S2 and N2 to lose access to S1.		older than the other mirror	add S1 to md0 on N2:
After the package resumes		half S1.	# mdadm --add /dev/md0
activity and runs for 20 seconds,		However, all data that was	/dev/hpdev/mylink-sde.
a second failure occurs causing		written to S1 after the FC	This command initiates the
N 1 to fail, perhaps due to power		link failure is lost
			re-mirroring process. When it is
failure.
			complete, the extended distance
			cluster detects S1 and accepts it as
			md0 again.
			For the second failure, restore N1.
			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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