13-7
User
Guide

for

the

Cisco

Application

Networking

Manager

5.2
OL-26572-01
Chapter
13






Configuring

High

Availability
Understanding
ACE

Redundancy
ACE
appliance

redundancy

uses

a

maximum

of

two

ACEs

to

ensure

that

your

network

remains
operational
even

if

one

of

the

ACE

appliances

becomes

unresponsive.
Note
Redundancy
is

supported

between

ACEs

of

the

same
type
only.

Redundancy
is

not

supported

between
an
ACE

appliance

and

an

ACE

module

operating

as

peers.

Redundancy

must

be

of

the

same

ACE

device
type
and

software

version.
For
additional

information

about

ACE

redundancy,

see

either

the

Cisco

Application

Control

Engine
Module
Administration

Guide

or

t

he

Cisco

4700

Series

Application

Control

Engine

Appliance
Administration
Guide.
This
section

includes

the

following

topics:

•
ACE
High

Availability

Polling,
page
13-7

•
ACE
Redundancy

Protocol,

page
13-8

•
ACE
Stateful

Failover,

page
13-9

•
ACE
Fault-Tolerant

VLAN,

page
13-10

•
ACE
Configuration

Synchronization,

page
13-11

•
ACE
Redundancy

Configuration

Requirements

and

Rest

rictions,

page
13-12

•
ACE
High

Availability

Troubleshooting

Guidelines,

page
13-12
ACE
High

Availability

Polling
Approximately
every

two

minutes,

the

ANM

issues

the

show

ft

group

command

to

the

ACE

to

gather
the
redundancy

statistics

of

each

virtual

context.

The

state

information

is

displayed

in

the

HA

State

and
HA
Autosync

fields

when

you

cl

ick

Config

>

Devices

>

virtual

context.
Note
To
display

statistics

and
status
information

for
a
particular
high

availability

group
displayed

in

the

High
Availability
(HA)

Setup

window

(Config

>

Devices

>

admin_context

>

High

Availability

(HA)

>

Setup),
see
th

e

“Displaying

High

Availability

Group

Statistics

and

Status”

section

on

page

13-21 .
The
possible

HA

states

are

as

follows:

•
Active—Local
member

of

the
FT
group

is

active

and

processing

flows.

•
Standby
Cold—Indicates
if

the

FT

VLAN

is

down

but

the

peer

ACE

is

still

alive,

or
the
configuration
or

application

state

synchronization

failed.

When

a

context

is

in

this

state

and

a
switchover
occurs,

the

transition

to

the

ACTIVE

state

is

stateless.

•
Standby
Bulk—Local
standby
context
is

waiting

to

receive

state

information

from

its

active

peer
context.
The

active

peer

context

receives

a

notification

to

send

a

snapshot

of

the

current

state
information
for

all

applications

to

the

standby

context.

•
Standby
Hot—Local

standby
context

has

all

the

state

information
it
needs

to

statefully

assume
the
active
state

if

a

switchover

occurs.

•
Standby
Warm—Allows

the

configuration

and

state
synchronization

process

to
continue
on

a
best-effort
basis

when

you

upgrade

or


downgrade

the

ACE

sof

tware.