8-72
User
Guide

for

the

Cisco

Application

Networking

Manager

5.2
OL-26572-01
Chapter
8






Configuring

Real

Servers

and

Server

Farms
Configuring
Health

Monitoring
VM
Probe

Attributes
Note
You
use
a

VM

probe

when

you

configure

the

ACE

for

Dynamic

Workload
Scaling
(see

the
“Configuring
Dynamic
Workload

Scaling”

section

on

page

8-26 ),

which

requires

that

the

ACE

appliance

or

module

is
using
software

Version

A4(2.0)

or

a

later

release.
You
configure

the

VM

probe

attributes

to

control

when

the

ACE

bursts

traffic

to

remote

VMs

based

on
an
average

of

local

VM

CPU

usage,

memory

usage,

or

both.

The

ACE

obtains

the

usage

information

by
sending
the

VM

probe

to

the

specified

VM

Controller

associated

with

the

local

VMs

(see

Figure

1-1 ).

It
calculates
the

average

aggregate

load

information

for

all

local

VMs

as

a

percentage

of

CPU

usage

or
memory
usage

and

uses

either

or

both

percentages

to

determine

when

to

burst

traffic

to

the

remote

data
center.
If

the

server

farm

consists

of

both

physical

servers

and

VMs,

the

ACE

considers

load

information
only
from

the

VMs.
By
default,

the

VM

probe

checks

the

percentage

of

usage

for

either

the

CPU

or

memory

against

the
maximum
threshold

value.

Whichever

percentage

reaches

its

maximum

threshold

value

first

causes

the
ACE
to

burst

traffic

to

the

remote

data

center.

The

default

maximum

burst

threshold

value

of

99

percent
instructs
the

ACE

to

always

load

balance

traffic

to

the

local

VMs

unless

the

load

value

is

equal

to
100
percent

or

the

VMs

are

not

in

the

Operational

state.

If

you

configure

the

maximum

burst

threshold
value
to

1

percent,

the

ACE

always

bursts

traffic

to

the

remote

data

center.
When
the

usage

percentage

is

less

than

the

minimum

threshold

value,

the

ACE

stops

bursting

traffic

to
the
remote

data

center

and

continues

to

load

balance

traffic

to

the

local

VMs.

Any

active

connections

to
the
remote

data

center

are

allowed

to

complete.
Ta
b

l

e


8-33

lists

the

VM

probe

attributes.
To
associate

the

VM

probe

with

a

server

farm,

see

the

“Configuring

Server

Farms”

section

on

page

8-30 .
Related
Topics

•
Configuring
Dynamic

Workload

Scaling,

page
8-26

•
Configuring
Server
Farms,
page
8-30

•
Dynamic
Workload

Scaling

Overview,

page
8-4
Ta
b

l

e


8-33
VM
Probe

Attributes
Field
Action
Max
CPU

Burst
Threshold
Percentage
of
CPU

usage

by

the

local

VMs

at

which

the

ACE

begins

to

burst

traffic

to

the

remote
VMs.
Enter

a

value

from

1

to

99.

The

default

is

99.
Min
CPU

Burst
Threshold
Percentage
of

CPU

usage

by

the

local

VMs

below

which
the

ACE

stops
bursting
traffic
to
the
remote
VMs.

Enter

a

value

from

1

to

99.

The

default

is

99.
Max
Memory

Burst
Threshold
Percentage
of

memory

usage
by
the
local
VMs

at
which

the

ACE

begins
to
burst

traffic

to

the
remote
VMs.

Enter

a

value

from

1

to

99.

The

default

is

99.
Min
Memory

Burst
Threshold
Percentage
of

memory

usage

by

the
local

VMs

below

which

the

ACE

stops

bursting

traffic

to

the
remote
VMs.

Enter

a

value

from

1

to

99.

The

default

is

99.
VM
Controller

Name
Identifier
of

the

VM

Controller

that

is

associated

with

the

local

VMs

and

that

you

configured

in
the
“Configuring

and

Verifying

a

VM

Controller

Connection”

section

on

page

8-29 .

Click

the

radio
button
for

the

VM

Controller.