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 scenario is an extension of

If the FC links are not

Complete the following procedure

the previous failure scenario. In

restored on N2, you can only

to initiate a recovery:

the previous scenario, when the

start the package forcefully.

1. Reconnect the FC links

package fails over to N2, it does

You can forcefully start a

not start as the value of

package only if it is

between the data centers. As a

RPO_TARGET would have been

determined that the

result, S1

exceeded.

 

associated data loss is

(/dev/hpdev/mylink-sde)

To forcefully start the package

acceptable.

becomes accessible from N2

 

2. Run the following command to

P1 on N2 when the FC links are

After you execute the force

not restored on N2, check the

start commands, package

add S1 to md0 on N2

package log file on N2 and

P1 starts on N2 and runs

# mdadm --add /dev/md0

execute the commands that

with md0 consisting of only

/dev/hpdev/mylink-sde

appear in it.

 

S2

 

 

 

 

(/dev/hpdev/mylink-sdf).

This command initiates the

 

 

 

re-mirroring process from S2 to

 

 

 

S1. When re-mirroring is complete,

 

 

 

the extended distance cluster

 

 

 

detects S1 and accepts it as part of

 

 

 

md0.

 

 

 

 

Chapter 4

93