HP Insight Recovery Technical White Paper

17
Fi
gure 11
–
Change Local Site to
Primary
/Recovery
buttons
As illustrated in Fi
gure 11
, the
Change Local
S
ite to Primary
button is only available when
the
local
site is in the
recovery site
role
, whereas the
Change Local
S
ite
to Recovery
button
is grayed
-
out at the
recovery site
. At the
primary site
th
e reverse is true,
that is
the Change Local Site to Recovery
button
is e
nabled, but the
Change Local Site to Primary
button
is grayed
-
out.
Insight Recovery and RTO
/
RPO C
onside
rations
Insight Recovery
1.0 provides support for up to 50
DR
-
protected
logical server
s (managed nodes).
When considering the RTO and RPO characteristics of an Insight Recovery solution,
you must
take a
number of factors into account, such as the number
of
logical server
s being protected, the
state of the
dis
k array and storage management
server
(CommandView EVA)
at the
primary site
, the state of the
inter
-
site communication
links
between the
primary
and
recovery site
s
, etc
.
Regarding recovery time (RT
O
)
consideration
s
, Insight Recovery
perform
s
recovery group startup in
approximately
4 to
5
minutes per
logical server
--
i
ncluding
logical server
activation time
. Therefore,
the maximum amount of time
required to failover 50 Logical Servers could be slig
htly more than four
hours, but this can vary depending on several factors
–
such as the actual number of DR
-
protected
logical servers
.
Referring
to the
hypothetical
Application Tiers
classification
in Table 1,
in that example
Insight
Recovery
would be a
suitabl
e
disaster recovery
solution
(
over
Metropolitan
area
distances
)
for Tiers 2,
3, and 4
–
but possibly not for
Tier 1
–
since the worst case total recovery time
for 50
logical server
s
may exceed two
hours.
Insight Recovery provides the ability to
specify a startup order at failover time, so that higher priority
applications
can be started before
those of
lower pri
ority, which is may be useful in addressing
specific RTO requirements.
Meeting r
ecovery point object
ives (RPO)
is
also
dependent on ma
ny factors
–
including whether the
failover was a planned
or unplanned failover scenario
, and in the case of an unplanned failover
--
Change Local Site to Recovery
(grayed
-
out since the site’s
current role is Recovery)
Change Local Site to Primary