13-6
User
Guide

for

the

Cisco

Application

Networking

Manager

5.2
OL-26572-01
Chapter
13






Configuring

High

Availability
Understanding
ACE

Redundancy

•
Understanding
ANM

High

Availability,
page
13-2

•
Configuring
ACE
High

Availability,

page
13-14

•
Understanding
ACE

Redundancy,

page
13-6
Recovering
From

an

HA

Database

Replication

Failure
This
section

provides

an

overview

of

the

database

replication

process

that

occurs

between

ANM

HA
active
and

standby

nodes

and

how

to

recover

from

a

replication

failure.
When
the

active

ANM

is

running

and

the

standby

ANM

is

just

starting

up,

the

active

ANM

copies

its
entire
database

to

the

standby

ANM.

This

process

normally

takes

from

a

few

seconds

to

a

few

minutes
depending
on

the

size

of

the

configuration

data

and

monitoring

data.

During

the

replication

process,

the
active
ANM

database

is

locked

and

the

active

ANM

cannot

be

stopped

or

restarted

usi

ng

t

he

anm-tool
command
nor

can

it

perform

a

failover.
It
is

possible

for

the

database

replication

process

to

fail

if

the

standby

ANM

is

stopped

or

powered

down,
the
connectivity

is

down,

or

the

active

ANM

is

powered

down.

The

failure

of

the

replication

process

does
not
affect

the

integrity

of

the

active

ANM

database.

The

procedure

in

this

section

describes

what

to

do
if
you

e

ncounter

a

re

plication

failure.
Procedure
Step
1
Check
the

standby

ANM

and

make

sure
that
it

has

stopped.
If
the

standby

ANM

is

still

running,

stop

it

because

its

database

might

be

incomplete

due

to

the
replication
failure.
Step
2
Check
the

connectivity

between

the

active
ANM
and

standby

ANM

and

make

sure

that

both

links

are

up
and
connected.
Step
3
Do
one

of

the

following:

•
If
the

active

ANM

is

still

running,

login

and

check

to

see

that
its
configuration

is

normal.

•
If
the

active

ANM

has

stopped

or

powered

down,

restart
it
now.
Step
4
After
the
active
ANM

is
running
normally,

restart

the

standby

ANM.
Caution
Do
not

restart
the
standby

ANM

before
the
active

ANM

is

running

and

operating

normally.
Step
5
From
the

standby

ANM

GUI,

choose
Admin
>

ANM

Management

to

display

the

ANM

Server

window
and
make

sure

that

the

HA

Replication

Status

is

set

to

OK

before

performing

any

daily

management
tasks.
Understanding
ACE

Redundancy
ACE
module

redundancy

(or

faul

t

tolerance)

uses

a

maximum

of

two

ACEs

in

the

same

Catalyst

6500
switch
or

in

separate

switches

to

ensure

that

your

network

remains

operational

even

if

one

of

the

modules
becomes
unresponsive.